AP BIOLOGY. Energy Processing. Slide 1 / 215. Slide 2 / 215. Slide 3 / 215. Energy Processing

Transcription

1 Slide 1 / 215 Slide 2 / 215 P IOLOGY Energy Processing Energy Processing Slide 3 / 215 lick on the topic to go to that section Photosynthesis Resource cquisition - Photosynthesis ellular Respiration Resource cquisition - ellular Respiration ioenergetics

2 Photosynthesis Slide 4 / 215 Return to Table of ontents The Sun Supplies the Energy of Life Slide 5 / 215 The energy of life begins as photons, created by nuclear fusion, traveling out of the sun at the speed of light. Photons are packets of electromagnetic radiation. Electromagnetic Waves Slide 6 / 215 Electromagnetic radiation is composed of an oscillating wave of magnetic and electric fields which travel through space The distance between the crests of the waves determines the wavelength, and the number of crests per unit time determines the frequency λ = ν f

3 Electromagnetic Radiation Slide 7 / 215 The wavelength (and frequency) of the electromagnetic radiation in a photon determines the energy in that photon λ = ν f short wavelength = high frequency = high energy long wavelength = low frequency = low energy Visible Light Slide 8 / 215 When the wavelength of electromagnetic radiation is between 400 and 700 nm, it can be detected by the human eye and is called visible light. Electromagnetic Spectrum Slide 9 / 215 Visible light is only a small portion of the entire light spectrum

4 Electromagnetic Radiation Slide 10 / 215 When we see a color, green for example, from an object it is because the object is absorbing some light waves while reflecting others. White light contains all color wavelengths. In this example what light waves are being absorbed? Pigments Slide 11 / 215 Pigments are substances that have the ability to absorb light. We perceive their color as the wavelengths that they are not able to be absorbed. 1 person's shirt looks red because red wavelength is being Slide 12 / 215 absorbed reflected

5 1 person's shirt looks red because red wavelength is being Slide 12 (nswer) / 215 absorbed reflected nswer 2 hlorophyll is a pigment found in plants. What color of light does chlorophyll absorb? Slide 13 / 215 white orange green all of the above 2 hlorophyll is a pigment found in plants. What color of light does chlorophyll absorb? Slide 13 (nswer) / 215 white orange green nswer all of the above

6 bsorption Spectrum Slide 14 / 215 This graph represents the absorption spectrum of chlorophyll. The 2 lines represent 2 types of chlorophyll. What colors do these pigments absorb? a b a b Pigments Slide 15 / 215 When electromagnetic radiation is absorbed, the energy contained in the photon is transferred to an electron which allows the electron to become excited. This means that the electron moves from a low energy level (ground state) to a higher energy level. Energy Transfer Slide 16 / 215 n excited electron is unstable in the higher energy level and must release the energy it gained from the photon. In a pigment molecule the energy can be released in several ways: - Fluorescence - Reaction initiation - Resonance transfer

7 Fluorescence Slide 17 / 215 If the electron has no other way to release its energy, it will drop back down to its ground state. s the electron drops to its ground state, energy is released as a photon. The energy released is slightly less than the energy, but with the same frequency, as the photon that excited the electron. This process is called fluorescence. Reaction Initiation Slide 18 / 215 The excited electron can provide the activation energy necessary to initiate a chemical reaction. For example, iodine is keep in dark-colored bottles because exposure to light initiates a reaction that degrades the iodine. Resonance Transfer If the excited electron is in close proximity to another pigment molecule, it can transfer its energy to an electron in the neighboring pigment molecule through a process called resonance transfer. The energy will continue to move between donor and acceptor pigment molecules without releasing a photon. Slide 19 / 215 Resonance Transfer

8 3 s the energy from photons is transferred to electrons, the electrons move to lower energy levels and are more stable. move to lower energy levels and are unstable. become excited and more stable. become excited and unstable. Slide 20 / s the energy from photons is transferred to electrons, the electrons move to lower energy levels and are more stable. move to lower energy levels and are unstable. become excited and more stable. become excited and unstable. Slide 20 (nswer) / 215 nswer 4 The process of electrons passing energy to electrons in neighboring pigment molecules is known as flourescence resonance photon transfer activation energy Slide 21 / 215

9 4 The process of electrons passing energy to electrons in neighboring pigment molecules is known as flourescence resonance photon transfer activation energy Slide 21 (nswer) / 215 nswer Evolution and Metabolism Slide 22 / 215 Early prokaryotes used pigment and its properties to trap light energy and utilize it to do work. They became more abundant because they had a new found, infinite energy source. s they became more abundant new variations began to emerge, with more efficient ways to utilize the energy source. Photosystems Slide 23 / 215 Photosystems are the first organic system to turn energy from sunlight into chemical energy. They are a conglomeration of protein pigmentsthat have the ability to use enzymatic activity and resonance transfer to produce a molecule TP. of ribbon diagram of a photosystem. Remember proteins are chains of amino acids that fold up onto each other to produce useful functions.

10 TP Slide 24 / 215 TP (adenosine triphosphate) is the currency of energy in living systems. It stores the energy gained in exergonic reactions to power endergonic reactions at a later time. TP provides the energy for the processes of life. TP Slide 25 / 215 TP (adenosine triphosphate) includes three phosphate groups (PO 4-3 ). Each Phosphate group has an ionic charge of -3e. In this space filling model of TP, each PO 4-3 is circled in blue. TP Slide 26 / 215 The phosphate groups repel each other, since they each have a negative charge. Therefore it requires Work to add the second phosphate group; to go from MP (monophosphate) to P (diphosphate). To add the third group, to go from P to TP (triphosphate), requires even more work since it is repelled by both of the other phosphate groups.

11 TP Slide 27 / 215 This is like the work in compressing a spring. The energy from the work needed to bring each phosphate group to the molecule is stored in that phosphate bond. When the bond is broken to go from TP to P, significant energy is released. Going from P to MP releases less energy, since there is less total charge in P than TP. TP Performs Work Slide 28 / 215 In living systems, the energy from the exergonic reaction of TP hydrolysis can be used to drive an endergonic reaction. TP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant. The recipient molecule is now "phosphorylated". The three types of cellular work are powered by the hydrolysis of TP: mechanical, transport, chemical. The Regeneration of TP Slide 29 / 215 TP is a renewable resource that is regenerated by addition of a phosphate group to P. The energy to phosphorylate P comes from catabolic reactions in the cell. Each cell is converting millions of TP to P and back again every second. TP Energy from catabolism (energonic, exergonic energyyielding processes) + P P i Energy for cellular work (endergonic, energyconsuming processes)

12 5 In general, the hydrolysis of TP drives cellular work by. releasing free energy that can be coupled to other reactions releasing heat acting as a catalyst lowering the free energy of the reaction Slide 30 / In general, the hydrolysis of TP drives cellular work by. releasing free energy that can be coupled to other reactions releasing heat acting as a catalyst lowering the free energy of the reaction Slide 30 (nswer) / 215 nswer 6 Which of the following is not an example of the cellular work accomplished with the free energy derived from the hydrolysis of TP? Mechanical work, such as the movement of the cell Transport work, such as the active transport of an ion into the cell hemical work, such as the synthesis of new proteins. Slide 31 / 215 The production of heat, which raises the temperature of the cell.

13 6 Which of the following is not an example of the cellular work accomplished with the free energy derived from the hydrolysis of TP? Mechanical work, such as the movement of the cell Transport work, such as the active transport of an ion into the cell hemical work, such as the synthesis of new proteins. nswer The production of heat, which raises the temperature of the cell. Slide 31 (nswer) / Which best characterizes the role of TP in cellular metabolism? The release of free energy during the hydrolysis of TP heats the surrounding environment. Slide 32 / 215 The free energy released by TP hydrolysis may be coupled to an endergonic process via the formation of a phosphorylated intermediate. It is catabolized to carbon dioxide and water. The ΔG associated with its hydrolysis is positive. 7 Which best characterizes the role of TP in cellular metabolism? The release of free energy during the hydrolysis of TP heats the surrounding environment. Slide 32 (nswer) / 215 The free energy released by TP hydrolysis may be coupled to an endergonic process via the formation of a phosphorylated intermediate. It is catabolized to carbon dioxide and water. nswer The ΔG associated with its hydrolysis is positive.

14 Photosystems Slide 33 / 215 Photosystems are embedded in membranes, thus they are a type of transport protein. The membrane is required to establish the proton gradient for the synthesis of TP. Outside the prokaryote (the environment) Inside the prokaryote (the biological system) Photosystems Slide 34 / 215 The first step in the process is when sunlight excites the electrons in the pigment of the system. Photosystems Slide 35 / 215 Electrons that reach sufficient energy levels are transferred from one part of the system to another. e-

15 Photosystems Slide 36 / 215 H+ The motive force is used to transfer hydrogen ions from the environment to the interior of the membrane. e- Photosystems Slide 37 / 215 H+ s time passes, a concentration gradient is formed. Low [H+] e- High [H+] Photosystems Slide 38 / 215 H+ This is known as a membrane potential,the charge difference can be used to power a system. Low [H+] e- High [H+]

16 TP Synthase Slide 39 / 215 In another location of the same membrane is a protein known as TP synthase. This molecule takes advantage of the gradient produced and generates TP. Low [H+] photosystem TP Synthase High [H+] TP Synthase Slide 40 / 215 Natural diffusion takes over and H+ travels back through the TP synthase. Low [H+] photosystem H+ High [H+] TP Synthase Slide 41 / 215 The motive force of the H+ spins the TP synthase and it acts as a turbine. Low [H+] photosystem H+ High [H+]

17 TP Synthase Slide 42 / 215 The energy captured is used to phosphorylate TP, a molecule that can be used to do work, power reactions, etc. P P i TP Low [H+] photosystem H+ High [H+] 8 Which best describes a photosystem? Slide 43 / 215 membrane bound proteins major enzyme activity center synthesizer of TP light reflector 8 Which best describes a photosystem? Slide 43 (nswer) / 215 membrane bound proteins major enzyme activity center synthesizer of TP light reflector nswer

18 9 The transfer of electrons in a photosystem creates a membrane potential with a concentration of H+ molecules on the inside of the membrane and a concentration on the outside of the membrane. higher; lower lower; higher Slide 44 / The transfer of electrons in a photosystem creates a membrane potential with a concentration of H+ molecules on the inside of the membrane and a concentration on the outside of the membrane. higher; lower lower; higher nswer Slide 44 (nswer) / 215 yclic Electron Transport Slide 45 / 215 s simple prokaryotes continued to evolve, the systems of TP synthesis and electron transport evolved more efficient and more complex systems. elow is a diagram ofcyclic electron transport. In this system electrons are returned to the pigments after proton transport.

19 yclic Electron Transport Slide 46 / 215 Notice the addition of cytochrome and the transport of electrons from the photosystem to this specialized protein that functions as an efficient transporter of hydrogens across the membrane. Using Nature to esign Technology Slide 47 / 215 n engineering student is interested in designing a solar panel that is more efficient than the current variety. s an elective, the student is taking a biology class and learns about cyclic electron transport. She decides that this system could be used to design a better solar panel. Work with a group and use what you have learned about cyclic electron transport to design a solar panel. Sketch out a flow chart of the system. an you think of any ways to improve upon your design? Evolution ontinues... Slide 48 / 215 Though this system was highly advanced at the time, evolution continued to tinker with the parts of this system to make it more efficient. One of the major problems with this system, is that the TP is being released outside the membrane. The cell must then uptake the TP from its surroundings.

20 Evolution ontinues... Slide 49 / 215 lso, TP is a good molecule for management of energy but cannot be used for storage of energy because its reactivity makes it break down quickly. So TP producing organisms can only survive when sunlight is available, or if they flood their environment with TP. Evolution ontinues... Slide 50 / 215 However, evolution was not just tinkering with the production of TP. Simultaneously other types of prokaryotes were being selected for other reasons. Evolution ontinues... Slide 51 / of the most important advancements of this era: Energy Storage- Glucose is produced by cells taking advantage of TP and carbon dioxide. This marks the beginning of sugar and carbohydrates on planet Earth.

21 Evolution ontinues... Slide 52 / of the most important advancements of this era: Symbiosis- acterial cells of different species tightly associate with one another and use each others' products as reactants. Glucose TP Endosymbiosis Slide 53 / 215 rguably the biggest progression in the evolution of life is the point at which prokaryotic cells begin to combine into more complex eukaryotic cells. Several species of prokaryote, each with a separate function, are believe to have come together to form one cell capable of multiple functions. Evidence supports the endosymbiotic origins of both chloroplasts and mitochondria. Endosymbiosis Slide 54 / 215 oth chloroplasts and mitochondria have their own N separate from the nuclear N. This N is circular, resembling that of prokaryotes. In addition, notice that as the smaller cells, known as plastids, are engulfed by the larger cells they become doubly wrapped in membranes. oth chloroplasts and mitochondria possess these double membranes. This endosymbiosis increases the metabolic ability of cells descendant of this process.

22 Evolution ontinues... Slide 55 / of the most important advancements of this era: ompartmentalization - Some cells begin to get infoldings and more complex systems of membranes. This produces isolated pockets that can house separate chemical reactions. ells can do multiple reactions without cross interference. 10 Which of the following serves as long term energy storage in cells? Slide 56 / 215 carbon-carbon bonds glucose TP both & 10 Which of the following serves as long term energy storage in cells? Slide 56 (nswer) / 215 carbon-carbon bonds glucose TP both & nswer

23 11 new organelle is discovered within a eukaryote. It is a single-membrane structure containing ribosomes and RN. Which of the following is likely true about this organelle? Slide 57 / 215 It is an endosymbiont It is involved in gene expression It is a plastid It is parasitic prokaryote 11 new organelle is discovered within a eukaryote. It is a single-membrane structure containing ribosomes and RN. Which of the following is likely true about this organelle? Slide 57 (nswer) / 215 It is an endosymbiont nswer It is involved in gene expression It is a plastid It is parasitic prokaryote hloroplasts Slide 58 / 215 This is a simple representation of a photosynthetic organelle. n organelle is a small molecular machine inside a cell. hloroplast O O 6H 12O 6

24 hloroplasts Slide 59 / 215 The chloroplast is a double-membraned structure that utilizes a concentration gradient and compartmentalization to maximize its production of the energy storage molecule glucose. 12 The inside of the thylakoid is called the and the outside is called the. lumen, stroma stroma, lumen Slide 60 / The inside of the thylakoid is called the and the outside is called the. lumen, stroma stroma, lumen Slide 60 (nswer) / 215 nswer

25 Photosynthesis Slide 61 / 215 From a combination of cyclic electron transport and the storing of energy in the bonds of carbon atoms, a new process is born, non-cyclic electron transport. hloroplasts use this process to produce all sugars and carbohydrates. Light Reactions Slide 62 / 215 The absorption of light and creation of TP, called the light reactions of photosynthesis, take place in the thylakoid membrane of the chloroplast. Light Reactions Photosystem II is the first structure in the series. Light excites the pigments of the photosystem and electrons are sent to the electron transport chain (ET). Simultaneously, water molecules are being split and providing their electrons to the photosystem. Water is the primary donor of electrons. Electrons are not returned to the pigments (non-cyclic). Slide 63 / 215

26 Light Reactions Slide 64 / 215 The electron transport chain moves protons as described in cyclic electron transfer. The electrons are no longer excited because of the energy transfer. They are then donated to the next step. Light Reactions Slide 65 / 215 Photosystem I re-excites the electrons using light energy. These high energy electrons are used to reduce a molecule of NP to NPH. This will carry the electrons to the second stage of photosynthesis: the alvin ycle. Light Reactions Finally, the proton gradient is used to generate TP. The enzyme TP synthase takes advantage of the energy of the hydrogen ions' natural diffusion down its gradient. The energy is used to attach a phosphate to P. Slide 66 / 215

27 Light Reactions Video Slide 67 / 215 lick for a video explanation of the Light Reactions 13 Water is split, releasing O 2, in which protein complex? Slide 68 / 215 photosystem I photosystem II TP synthase NP reductase 13 Water is split, releasing O 2, in which protein complex? Slide 68 (nswer) / 215 photosystem I photosystem II TP synthase NP reductase nswer

28 14 In non-cyclic electron transport water donates electrons to the process. Which of the following best describes what happens to these excited electrons? Slide 69 / 215 They are returned to the pigments They proceed to photosystem I They are used to phosphorylate TP They are transported to the alvin ycle via NPH 14 In non-cyclic electron transport water donates electrons to the process. Which of the following best describes what happens to these excited electrons? Slide 69 (nswer) / 215 They are returned to the pigments They proceed to photosystem I nswer They are used to phosphorylate TP They are transported to the alvin ycle via NPH 15 Which of the following directly powers the production of TP? Slide 70 / 215 electromagnetic radiation electron transport chain photosystem I proton gradient

29 15 Which of the following directly powers the production of TP? Slide 70 (nswer) / 215 electromagnetic radiation electron transport chain nswer photosystem I proton gradient alvin ycle Slide 71 / 215 The light dependent reactions are the first part of photosynthesis. The remaining reactions are called the alvin ycle. The alvin ycle uses NPH and TP produced from the light-dependent reactions to reduce O 2 and produce sugar - this is called carbon fixation. alvin ycle Slide 72 / 215 The sugar produced is a 3 carbon molecule called glyeraldehyde-3- phosphate (G3P). The alvin ycle must occur three times to produce 1 G3P since it only fixes one O2 molecule in each cycle. In 3 turns of the cycle we use 9 TP and 6 NPH and 3 O2 to make 1 3-carbon sugar

30 Photosynthesis Recap Slide 73 / 215 Photosynthesis consists of two separate series of chemical reactions that together serve to capture electromagnetic radiation and transform it into stored chemical energy. Light Reactions - occur in the thylakoid or on the thylakoid membrane - require light - use light, H2O, P, and NP + to produce O2, TP, and NPH alvin ycle - occurs in the stroma - creates sugars using O2, TP, and NPH - P and NP+ are released as byproducts Photosynthesis Equation Slide 74 / O H 2O + light 6H 12 O O H 2O 16 The alvin cycle is an anabolic pathway. Slide 75 / 215 True False

31 16 The alvin cycle is an anabolic pathway. Slide 75 (nswer) / 215 True False nswer TRUE 17 How many turns of the alvin cycle are necessary to produce one molecule of glucose? Slide 76 / How many turns of the alvin cycle are necessary to produce one molecule of glucose? Slide 76 (nswer) / nswer

32 18 arbon dioxide is absorbed through the leaves of the plant. This gas is utilized in the... Slide 77 / 215 cytoplasm lumen stroma thylakoid membrane 18 arbon dioxide is absorbed through the leaves of the plant. This gas is utilized in the... Slide 77 (nswer) / 215 cytoplasm lumen stroma nswer thylakoid membrane Resource cquisition - Photosynthesis Slide 78 / 215 Return to Table of ontents

33 Evolution ontinues Slide 79 / 215 Photosynthesis requires an input of light, carbon dioxide and water. In primitive plants, such as mosses and liverworts, as well as photosynthetic protists and prokaryotes, these nutrients can be obtained via simple diffusion. s the complexity of plants increased evolution has favored specific structures and processes to better absorb these nutrients from the environment. These more complex plants possess roots for absorbing water, vascular systems for transporting water, and leaves for absorbing photons and carbon dioxide. Slide 80 / 215 The Plant ody Slide 81 / 215 Two main sections to the plant body: the roots and the shoots. shoots roots

34 Functions of the Root System Slide 82 / 215 The 3 functions of the root system are to: (1) anchor the plant (2) absorb and transport minerals and water (3) store food Slide 83 / 215 Slide 84 / 215 Shoot System The shoot system consists of the stems, leaves, and reproductive structures

35 Parts of the Stem Slide 85 / 215 Stems are composed of nodes, where leaves, flowers, and other stems attach. Space between the nodes is the internode. Leaves are composed of photosynthetic blades and short stalks that attach at the nodes. Leaf uds Slide 86 / 215 uds are undeveloped shoots which have the potential to grow into nodes, internodes, and leaves. Types of uds Slide 87 / 215 Terminal uds are found at the top of the plant and are responsible for the growth in height. xillary (or lateral) uds are found at each point of attachment for a leaf and the stem and are responsible for growth in width.

36 19 The main function of the root hair is to Slide 88 / 215 increase anchoring power of the plant increase surface area for absorption protect roots from freezing temperatures provide a passageway for nutrients 19 The main function of the root hair is to Slide 88 (nswer) / 215 increase anchoring power of the plant increase surface area for absorption nswer protect roots from freezing temperatures provide a passageway for nutrients 20 Roots absorb... Slide 89 / 215 light carbon dioxide oxygen water

37 20 Roots absorb... Slide 89 (nswer) / 215 light carbon dioxide oxygen water nswer 21 bud can develop into which of the following? Slide 90 / 215 a node an internode a leaf all of the above 21 bud can develop into which of the following? Slide 90 (nswer) / 215 a node an internode a leaf nswer all of the above

38 Water cquisition Water and minerals absorbed by through root hairs passes into the xylem (1). The xylem sap, the water and dissolved nutrients of the xylem, gets transported long distances through the shoot system of the plant and into the leaves. Slide 91 / 215 Two factors allow for this bulk movement of water: (2) capillary action (3) transpiration apillary ction Slide 92 / 215 Recall that attraction between water molecules is termed cohesion. ttraction between a water and a non-water molecule is termed adhesion. apillary action relies on these properties to pull water up against gravity. Transpiration Slide 93 / 215 Transpiration is the evaporation of water from the leaves, stems, and flowers of plants. Water molecules evaporate via that somata - pores in the leaf that can be opened and closed to control the loss of water, as well as the exchange of gases such as oxygen and carbon dioxide. Underside of a leaf Stomata

39 Guard ells Slide 94 / 215 Guard cells are the cells on either side of the stomata pore. They work on a simple mechanism that does not require hormonal control. Guard ells Since the quickest path to plant death is loss of water, they allow the plant to exchange gas when water is plentiful but close when water is scarce. Guard ells Slide 95 / 215 When water is plentiful the guard cells central vacuole fills, like a balloon, and puts turgor force on the cell walls. The shape of the cells is such that they push against each other opening a pore. When water is scarce the central vacuole loses water and the turgor force is reduced, causing the pore to close and preventing gas exchange. Negative Pressure Slide 96 / 215 The loss of water through transpiration lowers the water potential of leaf cells, drawing water up the plant. tmospheric usually low Leaf depends on transpiration rate Root medium to high Soil high if moist What factors could affect the transpiration rate?

40 22 What property of water is responsible for water's cohesive and adhesive properties? Slide 97 / 215 Its ionization constant Its polarity Its heat capacity Its number of protons 22 What property of water is responsible for water's cohesive and adhesive properties? Slide 97 (nswer) / 215 Its ionization constant Its polarity Its heat capacity nswer Its number of protons 23 Which of the following allow for the exchange of gases between a plant and the atmosphere? Stomata Pressure potential Guard cells arrier proteins Slide 98 / 215

41 23 Which of the following allow for the exchange of gases between a plant and the atmosphere? Stomata Pressure potential Guard cells arrier proteins nswer Slide 98 (nswer) / Which of the following control the exchange of gases between a plant and the atmosphere? Stomata arrier proteins Guard cells Nothing; the exchange of gases is not controlled Slide 99 / Which of the following control the exchange of gases between a plant and the atmosphere? Stomata arrier proteins Guard cells Nothing; the exchange of gases is not controlled nswer Slide 99 (nswer) / 215

42 Gas Exchange In addition to water movement, stomata are also responsible for allowing the carbon dioxide necessary for photosynthesis to enter the leaves and for the release of excess oxygen. Slide 100 / 215 elow is a diagram of a typical leaf cell: Top Key - waxing coating to reduce evaporation E - epidermis to further protect the leaves P - mesophyll where the majority of photosynthesis occurs S & H - cells which comprise the stomata ottom Gas Exchange Slide 101 / 215 When the sun shines, photosynthesis increases as well as heat. What changes in gas will take place inside the leaf? Top Oxygen arbon ioxide Water Vapor ottom Gas Exchange Slide 102 / 215 s the suns rays hit the leaf O 2 is used more, O 2 is produced and more water is vaporized by the increased temp. Top Oxygen arbon ioxide Water Vapor ottom

43 Gas Exchange The concentration changes cause diffusion through the stomata down concentration gradients Slide 103 / 215 Top Oxygen arbon ioxide Water Vapor ottom Gas Exchange Slide 104 / 215 This allows a constant flow of O 2 for continued photosynthesis, unless the plant is low on water. Then the stomata must close and end the exchange. Top Oxygen arbon ioxide Water Vapor ottom 25 Which of the following is a plant's first line of defense from the rays of the sun? Stomata Mesophyll Guard cells Waxy cuticle Slide 105 / 215

44 25 Which of the following is a plant's first line of defense from the rays of the sun? Stomata Mesophyll Guard cells Waxy cuticle nswer Slide 105 (nswer) / In which type of plant cell would you expect to find the highest concentration of chloroplasts? Slide 106 / 215 epidermial cells guard cells cuticle cells mesophyll cells 26 In which type of plant cell would you expect to find the highest concentration of chloroplasts? Slide 106 (nswer) / 215 epidermial cells guard cells cuticle cells mesophyll cells nswer

45 27 plant is affected by a toxin which prevents guard cells from closing stomata. Which of the following would likely occur? Slide 107 / 215 The transpiration rate will decrease. There will be a buildup of oxygen in the spongy mesophyll. Photosynthetic rate will decrease due to a shortage of water. Photosynthetic rate will decrease due to a shortage of carbon dioxide. 27 plant is affected by a toxin which prevents guard cells from closing stomata. Which of the following would likely occur? Slide 107 (nswer) / 215 The transpiration rate will decrease. There will be a buildup of oxygen in the spongy mesophyll. Photosynthetic rate will decrease due to a shortage of water. Photosynthetic rate will decrease due to a shortage of carbon dioxide. nswer Gathering Sunlight Slide 108 / 215 n important feature of plants is their ability to grow toward sunlight. This is called phototropism. It ensures that the plant will optimize the amount of sunlight it can gather.

46 Gathering Sunlight Slide 109 / 215 botanist is growing some plants under an artificial light source and accidentally cuts the tops of some sprouting plants. fter a time she notices that the plants are not growing the same. ut Uncut Gathering Sunlight Slide 110 / 215 For some reason the cut plants do not grow toward the light. She hypothesizes that the tip of the plant is exhibiting hormonal control of the plant. Why might this occur? ut Uncut uxin Slide 111 / 215 Phototropism works because the tip of the plant produces auxin, a hormone that controls the length of cell growth in plant cells. This hormone runs down the stem. When light is directly overhead an equal amount of hormone travels down each side of the stem making the cells grow evenly. When the light is on one side of the plant more hormone travels down the dark side of the plant making these cells grow faster and the plant grow towards the light.

47 uxin is Plant Growth Hormone Slide 112 / 215 uxin naturally migrates away from light causing a concentration gradient. The further from the light the more auxin, more auxin = more elongation. 28 uxin is a hormone found in plants and is responsible for Slide 113 / 215 phototropism photoperiodism photosynthesis photosensitivity 28 uxin is a hormone found in plants and is responsible for Slide 113 (nswer) / 215 phototropism photoperiodism photosynthesis photosensitivity nswer

48 29 In which part of the plant is auxin found? Slide 114 / 215 root stem leaves nodes 29 In which part of the plant is auxin found? Slide 114 (nswer) / 215 root stem leaves nodes nswer 30 Placing a light on the left side of a plant will... Slide 115 / 215 increase the flow of auxin on the left side of the plant increase the flow of auxin on the right side of the plant cause the cells on the left side of the plant to grow more rapidly have no effect on the plant

49 30 Placing a light on the left side of a plant will... Slide 115 (nswer) / 215 increase the flow of auxin on the left side of the plant increase the flow of auxin on the right side of the plant nswer cause the cells on the left side of the plant to grow more rapidly have no effect on the plant Overview of the uxin Effect Slide 116 / (1) The hormone binds to an auxin receptor (2) This signal is transduced into second messengers within the cell (3) Proton pumps are activated, and secretion of acid loosens the wall, enabling the cell to elongate. Overview of the uxin Effect Slide 117 / (4) The Golgi apparatus is stimulated to discharge vesicles containing materials to maintain the thickness of the cell wall. (5) The signal-transduction pathway also activates N-binding proteins that induce transcription of specific genes. (6) This leads to the production of proteins required for sustaining growth of the cell.

50 pical ominance Slide 118 / 215 pical ominance results from the release of auxin by the terminal bud which inhibits the growth from the lateral buds. To made a plant bushier, you remove the terminal bud, which then allows for growth from the lateral buds. This is because the bud is removed, which means the hormone suppressing the growth is also removed. This is also why pruning makes fruit trees produce more fruit. Hormonal ontrol in Plants Slide 119 / 215 uxin is just one example of plants using hormones to exhibit whole organism control by effecting each cell. This example is just one of many hormones that control homeostasis and enable the plant to gain optimal growth and energy efficiency. Other Plant Hormones Slide 120 / 215 Gibberellin: Like auxin it promotes cell elongation, and it acts as a chemical messenger (hormone) to stimulate the synthesis of hydrolytic enzymes. These enzymes are important in the germination of seedlings to ensure the release of stored nutrients. Those nutrients feed the seedling's early development. This chemical hormone is sometimes used by the farming industry to promote growth. The grapes on the right were treated with a gibberellin solution.

51 ytokinins: Other Plant Hormones ytokinins stimulate cell division and differentiation in plants; usually coupled with auxin. ytokinins slow the process in which chlorophyll breaks down and various molecules and minerals are removed from leaves before they fall. Protein synthesis stops when leaves are picked, but if they are treated with cytokinin they remain green, protein synthesis continues, and carbohydrates do not break down. These cuttings were removed from their parent plant 7 weeks ago. The one on the right was genetically engineered to produce more ytokinins Slide 121 / uxin enhances cell elongation in all of these ways except... Slide 122 / 215 gene activation increased activity of proton pumps increased uptake of solutes cell wall loosening 31 uxin enhances cell elongation in all of these ways except... Slide 122 (nswer) / 215 gene activation increased activity of proton pumps nswer increased uptake of solutes cell wall loosening

52 32 Removing the terminal bud of a plant will cause: Slide 123 / 215 an increase in the root system an increase in the size of the leaves increased axillary bud growth a plant to lose the ability to flower 32 Removing the terminal bud of a plant will cause: Slide 123 (nswer) / 215 an increase in the root system an increase in the size of the leaves increased axillary bud growth nswer a plant to lose the ability to flower 33 Which hormone is incorrectly paired with its function? Slide 124 / 215 auxin - promotes cell growth through cell elongation cytokinins - controls phototrophism cytokinins - prevent chlorophyll degradation gibberellins - stimulate seed germination

53 33 Which hormone is incorrectly paired with its function? Slide 124 (nswer) / 215 auxin - promotes cell growth through cell elongation cytokinins - controls phototrophism nswer cytokinins - prevent chlorophyll degradation gibberellins - stimulate seed germination ellular Respiration Slide 125 / 215 Return to Table of ontents Sugar is Storage Only Slide 126 / 215 Just as TP cannot be used for storing energy, glucose is not usable as energy. Glucose must be converted back into TP before it can be used to do work.

54 Glucose onversion acteria Slide 127 / 215 In much the same way photosynthesis developed through evolution tinkering with energy production, the utilization of glucose utilization in bacteria continued to evolve to be more efficient. reakdown of Glucose Slide 128 / 215 uilding glucose is an anabolic process that builds single carbon atoms into a 6 carbon molecule by building chemical bonds using energy. The breakdown is exactly the opposite, or catabolic. six carbon molecule is broken into individual carbon atoms and energy is released from the broken chemical bonds. Glycolysis The earliest form of glucose breakdown is a catabolic reaction known as glycolysis. Slide 129 / 215 Glucose: 6 carbons 2 pyruvate 3 carbons each

55 Glycolysis Slide 130 / 215 It requires an oxidative molecule known as N+. Oxidative molecules pull electrons from other molecules. Once N+ takes on the electrons from glucose it becomes NH. 2 N+ 2 NH Glucose: 6 carbons 2 pyruvate 3 carbons each Glycolysis Slide 131 / 215 This process releases energy that can be used to phosphorylate P into TP. In total only 2 TP are released from a glucose molecule. Not very efficient when you consider it took 18 TP and many electrons to make the glucose molecule. 2 N+ 2 NH Glucose: 6 carbons 2 P + Pi 2 TP 2 pyruvate 3 carbons each Glycolysis nother problem, is that you will eventually use up the N+ because all the local molecules are being converted to NH, slowing the process. Slide 132 / N+ 2 NH Glucose: 6 carbons 2 P + Pi 2 TP 2 pyruvate 3 carbons each

56 Glycolysis Evolution's answer to this problem was a process capable of regenerating N+. This process is known as fermentation. Slide 133 / N+ 2 NH Glucose: 6 carbons 2 P + Pi 2 TP 2 pyruvate 3 carbons each Fermentation Slide 134 / 215 Fermentation breaks down the products of glycolysis so that glycolysis can be repeated with another glucose molecule. These two processes, glycolysis and fermentation, are anaerobic: requiring no oxygen. 2 NH 2 3H4O3 (Pyruvate) Fermentation 2 N + Lactic cid Fermentation OR Ethanol Fermentation 2 Lactic cid O2 & 2 Ethanol Fermentation Slide 135 / 215 In glycolysis, 1 glucose molecule had yielded 2 TPs, 2 pyruvates and 2 NHs. That is the input to the fermentation stage of anaerobic respiration. 2 NH 2 3H4O3 (Pyruvate) Fermentation 2 N + Lactic cid Fermentation OR Ethanol Fermentation 2 Lactic cid O2 & 2 Ethanol

57 Fermentation Slide 136 / 215 In glycolysis, 1 glucose molecule had yielded 2 TPs, 2 pyruvates and 2 NHs. That is the input to the fermentation stage of anaerobic respiration. The pyruvates and NHs are fermented into 2 N + and either Lactic cid or O2 & Ethanol. 2 NH 2 N + Lactic cid Fermentation 2 3H4O3 (Pyruvate) 2 Lactic cid Fermentation OR Ethanol Fermentation O2 & 2 Ethanol naerobic Respiration Slide 137 / 215 The overall result of anaerobic respiration: The input is 1 Glucose + 2 TP molecules The output is 4 TP molecules (for a net gain of 2 TP's) In addition, Lactic cid fermentation results in lactic acid Ethanol fermentation results in ethanol and O2 34 When a cell has completed glycolysis and lactic acid fermentation, the final products are: I, II, III, IV, V I, II, III, V I, IV, V I, V I Lactic acid II Ethanol III arbon dioxide IV NH V TP Slide 138 / 215

58 34 When a cell has completed glycolysis and lactic acid fermentation, the final products are: Slide 138 (nswer) / 215 I, II, III, IV, V I, II, III, V I, IV, V I, V I Lactic acid II Ethanol III arbon dioxide IV NH nswer V TP Photosynthesis and Oxygen Slide 139 / 215 s life began to use photosynthesis as the primary means of capturing light energy, the by-product oxygen began to build up on planet Earth. Over ILLIONS of years, the early atmosphere was transformed into an oxygen-rich environment. This phenomenon made the next step in the evolution of glucose breakdown possible. Oxygen and Oxidation Slide 140 / 215 Oxygen is highly electronegative, which means it attracts electrons and pulls them from other molecules. This is an oxidative process. When oxygen takes on new electrons it is reduced, this refers to its drop in charge. e- O Reductive agent eing oxidized Oxidizing agent eing reduced

59 Redox Slide 141 / 215 Redox is the term used to describe this process. It notes that one molecule must be reduced in order to oxidize another. It is essentially the transfer of an electron. e- O Reductive agent eing oxidized Oxidizing agent eing reduced Redox Slide 142 / 215 Oxidation loses electrons 6 O H 2O + light 6H 12 O O H 2O Reduction gains electrons The overall reaction for photosynthesis is a redox reaction. Redox Slide 143 / 215 Oxidation loses electrons 6 O H 2O + light 6H 12 O O H 2O Reduction gains electrons H 2O is oxidized when it is converted to O 2 (it loses an electron). O 2 is reduced when it is converted into a sugar (it gains an electron). H 2O is the reducing agent because it donates and electron. O 2 is the oxidizing agent because it accepts an electron.

60 35 The loss of an electron is and the gain of an electron is. oxidation, reduction reduction, oxidation catalysis, phosphorylation phosphorylation, catalysis Slide 144 / The loss of an electron is and the gain of an electron is. oxidation, reduction reduction, oxidation catalysis, phosphorylation phosphorylation, catalysis nswer Slide 144 (nswer) / What happens to NH molecules during fermentation? Slide 145 / 215 they are oxidized they are reduced they are used to generate TP they are hydrolyzed

61 36 What happens to NH molecules during fermentation? Slide 145 (nswer) / 215 they are oxidized they are reduced they are used to generate TP nswer they are hydrolyzed 37 N+ in cellular respiration and NP+ in photosynthesis have very similar structures and are utilized for the same function. Given this, the NP+ is... Slide 146 / 215 used to power TP synthase is reduced during photosynthesis transported across the membrane a pigment 37 N+ in cellular respiration and NP+ in photosynthesis have very similar structures and are utilized for the same function. Given this, the NP+ is... Slide 146 (nswer) / 215 used to power TP synthase is reduced during photosynthesis nswer transported across the membrane a pigment

62 38 In the given pairs, is a oxidizing agent; is a reduced form. Slide 147 / 215 NP + ; NPH NH; N + O 2; H 2O O 2; O 2 38 In the given pairs, is a oxidizing agent; is a reduced form. Slide 147 (nswer) / 215 NP + ; NPH NH; N + O 2; H 2O O 2; O 2 nswer erobic ellular Respiration Slide 148 / H 12 O 6 + 6O 2 6O 2 + 6H 2 O + Energy Energy in this equation is in 2 forms: - TP for use in coupled reactions - Heat released as entropy This reaction is a redox reaction. - Which molecules are being reduced? - Which molecules are being oxidized?

63 erobic Respiration Slide 149 / 215 6H 12O 6 + 6O 2 6O 2 + 6H 2O + Energy This equation represents the overall reaction, but it is happening in three stages. 1) Glycolysis - the splitting of glucose into 2 pyruvic acid (pyruvate) molecules in the cytoplasm of a cell. 2) The citric acid cycle (Krebs cycle) - the stripping of electrons from the pieces of the glucose molecule in the mitochondria. 3) Oxidative phosphorylation - Using the electrons to set up a concentration gradient and energize the formation of TP in the mitochondria. Glycolysis Slide 150 / 215 This is the first stage of aerobic respiration. 2 N + 6H 12O 6 (Glucose) 2 TP 2 NH Gycolysis 2 3H 4O 3 (Pyruvate) 4 TP ounting the Molecules Slide 151 / 215 What is the net number of molecules present after glycolysis of 1 glucose molecule? (lick on the box to reveal the answer) TP arbon ioxide NH 2 0 2

64 Mitochondria In the same way that the prokaryotic chloroplast became part of the more complex eukaryotic cell, mitochondria also became part of the eukaryotic cell. This evolutionary process is known as endosymbiosis. Slide 152 / 215 Mitochondria Mitochondria specialized in the breakdown of glucose into TP, or cellular respiration. They represent the state of the art in glucose breakdown in biological machinery. Slide 153 / 215 They are extremely efficient, producing about 36 TPs per glucose molecule by using the oxidizing power of oxygen. Entering the Mitochondria Slide 154 / 215 Pyruvate will be broken down further in the citric acid cycle. First the pyruvate must enter the mitochondria which is the site of this cycle. In the process of transport, a carbon atom is striped from each of the pyruvate molecules. The carbon leaves the system as carbon dioxide. o-enzyme is combined with the remainder of the pyruvate molecule. The pyruvate is thus changed into a molecule called acetyl o and 2 more molecules of NH are produced. This process is known as decarboxylation and it occurs with the help of enzymes called the pyruvate dehydrogenase complex.

65 ounting the Molecules Slide 155 / 215 How many of each of the following molecules are produced from glycolysis and the uptake of pyruvate into the mitochondria per glucose molecule? (lick on the box to reveal the answer) TP arbon ioxide NH itric cid ycle Slide 156 / 215 The itric cid ycle, sometimes called the Krebs cycle, takes place within the mitochondrial matrix. It is the cycle that finishes the complete breakdown of the glucose molecule. It is a metabolic pathway made up of 8 steps and produces carbon dioxide, TP, NH and another electron transport molecule called FH 2 itric cid ycle Slide 157 / 215 This shows one cycle, which is due to one cetyl o- molecule. To account for one glucose molecule, two cycles are needed. Let's tally up the output for one cycle to confirm our results.

66 The itric cid ycle Slide 158 / 215 This is one turn of the cycle, due to 1 cetyl o-. Note the production of: 1 TP 3 NH 1 FH 2 How many O 2 molecules are produced in one turn of the cycle? ounting the Molecules Slide 159 / 215 How many of each of the following molecules in total are produced from the process of glycolysis, pyruvate decarboxylase Process, and the citric acid cycle per glucose molecule? (lick on the box to reveal the answer) TP arbon ioxide NH FH 2 2 Slide 160 / 215 NH and FH 2 These 2 molecules are used to make the bulk of the TP produced by aerobic cellular respiration in the last step. They have been harvesting electrons, reduced, as the glucose molecule has broken down through the previous processes. They will now shuttle those electrons to be used in oxidative phosphorylation where they will offload the electrons, becoming oxidized.

67 NH and FH 2 Slide 161 / 215 NH is the reduced version of N +. It carries enough energy to produce 3 TP molecules. FH 2 is the reduced version of F. It carries enough energy to produce 2 TP molecules. F FH2 Oxidative Phosphorylation Slide 162 / 215 This is the final process of aerobic cellular respiration. The energy from the electrons harvested from the previous steps is used to set up a proton concentration gradient across the inner membrane of the mitochondria. Then the gradient is used to power the production of 32 TP molecules. This takes place in two steps: 1) Electron transport chain - uses the energy in the electrons to actively transport protons against their gradient. 2) hemiosmosis - protons pass through a passive transport molecule that is also an enzyme called TP synthase with their gradient. Electron Transport hain Slide 163 / 215 lick here for a video of the Electron Transport hain

68 hemiosmosis Slide 164 / 215 lick here for a video of hemiosmosis ounting the Molecules Slide 165 / 215 How many of each of the following molecules are present after the complete breakdown of a glucose in aerobic respiration? (lick on the box to reveal the answer) TP arbon ioxide NH (Oxidized by ET) FH 2 0 (Oxidized by ET) 39 Which of the following correctly shows the steps of aerobic respiration? Slide 166 / 215 glycolysis-pyruvate decarboxylation-calvin cycle-oxidative phosphorylation glycolysis-pyruvate decarboxylation-citric acid cycle-oxidative phosphorylation fermentation-citric acid cycle-oxidative phosphorylation glycolysis-citric acid cycle-electron transport chain

69 39 Which of the following correctly shows the steps of aerobic respiration? Slide 166 (nswer) / 215 glycolysis-pyruvate decarboxylation-calvin cycle-oxidative phosphorylation glycolysis-pyruvate decarboxylation-citric acid cycle-oxidative phosphorylation nswer fermentation-citric acid cycle-oxidative phosphorylation glycolysis-citric acid cycle-electron transport chain 40 Which of following processes occur in the mitochondria? Slide 167 / 215 Krebs cycle pyruvate decarboxylation oxidative phosphorylation all of the above 40 Which of following processes occur in the mitochondria? Slide 167 (nswer) / 215 Krebs cycle pyruvate decarboxylation nswer oxidative phosphorylation all of the above

70 Resource cquisition - ellular Respiration Slide 168 / 215 Return to Table of ontents Gathering Oxygen Slide 169 / 215 Unlike plants, which undergo cellular respiration utilizing the products of their own chloroplasts, animals must obtain oxygen and glucose from their environment. We have seen how the human body absorbs and regulates glucose but we also need to extract oxygen and transport these molecules throughout the body. Respiratory System Slide 170 / 215 The function of the respiratory system is to exchange oxygen and carbon dioxide in an organism for the purpose of maintaining cellular respiration. The part of an animal where gases are exchanged with the environment is called the respiratory surface. Respiratory surfaces must be moist in order to function properly because gases are dissolved in water before diffusing across these surfaces.

71 Examples of Respiratory Systems Slide 171 / 215 Some animals, such as earthworms, use their entire outer skin as a respiratory organ. Other animals have body parts that are adapted for respiration because their skin surfaces are not extensive enough to provide gas exchange for the entire body. Examples of these include gills in fish, and lungs in mammals. Gas Exchange in Lungs Slide 172 / 215 Lungs are made of tiny sacs called alveoli. These are filled with arteries and veins that drop off carbon dioxide and retrieve oxygen to disperse through the organism In mammals, the rate at which lungs exchange gases with the environment is controlled primarily by ph. Gas Exchange in Lungs Slide 173 / 215 s carbon dioxide builds in the blood, the blood becomes more acidic. The brain respond to this stimuli by quickening alveoli contractions to expel this gas.

72 irculatory System Slide 174 / 215 In animals with multiple cell layers, a circulatory system is necessary to absorb the oxygen and glucose from the respiratory and digestive systems, and deliver these reactants to cells throughout the body. In exchange waste molecules, such as carbon dioxide, are picked up and carried away from the cells for excretion. There are 3 components to a circulatory system: 1. set of interconnecting tubes (vessels) 2. fluid to fill the tubes (blood or hemolymph) 3. pump to move the fluid throughout the body (heart) There are two types of circulatory systems: open systems and closed systems Open irculatory System Slide 175 / 215 Open circulatory systems are found in arthropods (such as a grasshopper or lobster) and most mollusks (such as a clam or oyster). The heart in these systems pumps the circulatory fluid, called hemolymph, directly into the spaces between the organs. There is no distinction between circulatory fluid and interstitial fluid. Relaxation of the heart draws the hemolymph back through pores for waste excretion. losed irculatory System Slide 176 / 215 In a closed circulatory system, blood is confined to vessels and is distinct from the interstitial fluid. These systems are more efficient at transporting circulatory fluids to tissues and cells. There are three types of vessels in a closed circulatory system: rteries : arry blood away from the heart to other organs and tissues of the body (remember way rtery) Veins: Return blood to the heart apillaries : Microscopic blood vessels that infiltrate each tissue in the body and diffuse nutrients to the cells.

73 lood Slide 177 / 215 lood consists of several kinds of cells and cell products suspended in a liquid matrix called plasma.the cellular elements make up about 45% of the total volume of blood. There are two types of cells suspended in the blood plasma: Erythrocytes (Red blood cells): transport oxygen. Leukocytes (White blood cells): function in defense/immunity. third cellular element, platelets, are not really true cells but are actually fragments of larger cells. They are involved in the normal clotting process of blood. The Heart Slide 178 / 215 The heart is a muscle for pumping circulatory fluid through the vessels. Invertebrates, both those with open and closed systems, typically have one or more tubular hearts moving fluid. ody movement also assists the flow of fluid through the system. Vertebrates have two and four chambers in their heart depending of their class. The increase in chamber number is advantageous for separating oxygenated and deoxygenated blood in the system. Vertebrate Hearts Slide 179 / 215 Fish have a 2-chambered heart: one ventricle and one atrium. lood moves from the atrium into the ventricle where it is pumped to the gills for oxygenation. Thus, oxygenated blood moves through body with very low pressure. Swimming assists the movement of fluid through the system.

74 Vertebrate Hearts Slide 180 / 215 mphibians have 3-chambered hearts: two atria and one ventricle. This creates a double loop circulation, blood leaving the ventricle moves through the lungs before returning to heart to be pumped to the body. What advantages does this system have over the 2-chambered heart? What are its disadvantages? Vertebrate Hearts Slide 181 / 215 Reptiles have a 3- chambered heart, similar to amphibians except the ventricle is partially divided. rocodilians have a completely divided ventricle. What advantages does this system have over the amphibian heart? What are its disadvantages? Vertebrate Hearts Slide 182 / 215 Mammals and birds have 4- chambered hearts (two atria and two ventricles). lood from the body enters the right atrium of the heart where it is pumped through the right ventricle to the lung. lood returns to the left ventricle and left atrium to be pumped to the body systems. What advantages does this system have over the previous structures? What are its disadvantages?

75 41 Red blood cells, whose main function is to transport oxygen, are more properly known as. Slide 183 / 215 erythrocytes leukocytes thrombocytes platelets 41 Red blood cells, whose main function is to transport oxygen, are more properly known as. Slide 183 (nswer) / 215 erythrocytes leukocytes thrombocytes platelets nswer 42 Which type of circulatory system is found in a fruit fly? Slide 184 / 215 closed circulatory system double-loop system open circulatory system single-loop system

76 42 Which type of circulatory system is found in a fruit fly? Slide 184 (nswer) / 215 closed circulatory system double-loop system nswer open circulatory system single-loop system 43 How many atria are in a human heart? Slide 185 / How many atria are in a human heart? Slide 185 (nswer) / 215 nswer 4

77 44 Where would the highest proportion of oxygenated erythrocytes be found? Slide 186 / 215 amphibian vein reptilian vein amphibian artery mammalian artery 44 Where would the highest proportion of oxygenated erythrocytes be found? Slide 186 (nswer) / 215 amphibian vein reptilian vein nswer amphibian artery mammalian artery 45 Hemoglobin is the protein in erythrocytes which binds oxygen and carbon dioxide molecules for transport through the blood. Studies have shown that hemoglobin has a higher affinity for carbon dioxide in acidic environments. Which of the following is true? Slide 187 / 215 The ph of mammalian blood in the lungs is <7 The ph of reptilian blood in the capillaries is <7 The ph of fish blood is consist throughout the system The ph of amphibian blood is lower in the arteries

78 45 Hemoglobin is the protein in erythrocytes which binds oxygen and carbon dioxide molecules for transport through the blood. Studies have shown that hemoglobin has a higher affinity for carbon dioxide in acidic environments. Which of the following is true? Slide 187 (nswer) / 215 The ph of mammalian blood in the lungs is <7 nswer The ph of reptilian blood in the capillaries is <7 The ph of fish blood is consist throughout the system The ph of amphibian blood is lower in the arteries 46 The binding sites of carbon dioxide and oxygen are located separately on the hemoglobin protein. When oxygen is bound to hemoglobin, the protein cannot bind carbon dioxide. Which of the following is false regarding hemoglobin interactions with these gases? Slide 188 / 215 inding these molecules causes a change in the tertiary structure of the protein The reaction with carbon dioxide is allosterically inhibited by oxygen The transport of gases through the circulatory system relies on competitive inhibition Lowering the ph of the environment will cause hemoglobin to release oxygen molecules 46 The binding sites of carbon dioxide and oxygen are located separately on the hemoglobin protein. When oxygen is bound to hemoglobin, the protein cannot bind carbon dioxide. Which of the following is false regarding hemoglobin interactions with these gases? Slide 188 (nswer) / 215 inding these molecules causes a change in the tertiary structure of the protein nswer The reaction with carbon dioxide is allosterically inhibited by oxygen The transport of gases through the circulatory system relies on competitive inhibition Lowering the ph of the environment will cause hemoglobin to release oxygen molecules

79 Summarizing the Energy Flow of Life Slide 189 / 215 Working in small groups, create a flow chart that shows the flow of energy through a cell. Start like this... The sun makes photons photons excite electrons in the pigment of a chloroplast irections ontinued... Summarizing the Energy Flow of Life Slide 190 / 215 To help frame this activity, think of a cell in a leaf which has both chloroplasts and mitochondria. How does this leaf cell produce the chemical energy that will directly do work in the cell? e as detailed as possible. The groups should combine their flowcharts into one detailed study guide for the whole class. Wrap-up of Life and Energy Slide 191 / 215 Living systems require free energy and matter to maintain order, grow and reproduce utotrophic cells capture free energy through photosynthesis. ellular respiration and fermentation harvest free energy from sugars to produce free energy carriers, including TP. The free energy available in sugars drives metabolic pathways in cells. Photosynthesis and respiration are interdependent processes.

80 ioenergetics Slide 192 / 215 Return to Table of ontents ioenergetics Slide 193 / 215 Gathering or managing energy is the first consideration for any species because without efficient bioenergetics all other metabolic processes will fail. For this reason most specializations of biological systems are the result of adaptations to gather energy. ioenergetics Slide 194 / 215 General view of energy management in animals. Heat Food Heat Heat Heat iosynthesis move/transport TP uild structures with carbon ellular Respiration reakdown by igestion Nutrients enter cells Get arbon Waste Waste Waste Waste Waste

81 Energy Strategies Slide 195 / 215 ll organisms must maximize efficiency in the getting and using of food for energy. However, each species achieves this with a different energy strategy. There are 2 factors that contribute to Heat Food the bioenergetics of any species: daptations - Which variations became available to the species. Environment - Which adaptations were effective in the environment. Heat Heat move/transport iosynthesis TP uild structures with carbon Waste Waste Heat reakdown by igestion ellular Respiration Nutrients Waste enter cells Get arbon Waste Waste Energy Strategies Slide 196 / 215 Lets compare 2 different animal species and examine their energy strategies. Species 1: The wolffish is generally about 5 feet long and weighs about 40 pounds. It has an eel-like body and swims slowly. It has six fanglike teeth, and three rows of crushing teeth.they like cold water. Their blood contains a natural antifreeze. Their favorite food is sea urchins and green crabs. Energy Strategies Slide 197 / 215 Let's compare 2 different animal species and examine their energy strategies. Species 2: lion is one of the largest members of the cat family. They typically live in frica. Lions are animals that usually hunt in groups. Weights for adult lions are around 500 lb. Lions spend much of their time resting and are inactive for about 20 hours per day. They spend an average of two hours a day walking and 50 minutes eating. They eat large herbivores.

82 Energy Strategies Slide 198 / 215 Using the information on the previous slides and information you already know about fish and lions, draw a chart that examines the similarities and differences between the energy strategies of these 2 animals. Once you have a list explain how the differences are adaptations to the given environment. Energy Strategies Slide 199 / 215 One of the major differences between these and other animals is the overall strategy of being endothermic, warm blooded, or ectothermic, cold blooded. Each of these energy strategies has strengths and weaknesses. Ectotherms Slide 200 / 215 Ectotherms are "cold blooded" animals. Most animals fit into this category. Most of their heat energy escapes into the environment so their body temperature is close to that of their surroundings. ctivity of these animals is drastically affected by temperature changes in their environment. When outside temperatures rise, they become more active. When external temperatures drop, they become more sluggish in their activity.

83 Ectotherms Slide 201 / 215 ons: When an animal is cold the chemical reactions that drive metabolic pathways slow down considerably. This means when they are cold they cannot move quickly. old blooded animals must rely on environmental factors to supply heat or have a warm up period before they can move at a faster speed. When they are cold they are more vulnerable to predators because they cannot react quickly to get away. Ectotherms Slide 202 / 215 Pros: Since these animals do not have to maintain a high body temperature they can minimize the amount of cellular respiration necessary for generating heat and staying alive. This means they require less food and can expend even less energy because they minimize the need to hunt for food. Endotherms Slide 203 / 215 Endotherms are the "warm blooded" animals, such as mammals and birds. These animals have evolved homeostatic mechanisms that allow them use the heat they generate. They have adaptations such as hair, fur, feathers, and fat that help prevent heat loss. They maintain constant body temperatures that are higher than their environment.

84 Endotherms Slide 204 / 215 ons: Warm blooded animals burn far more calories (unit of energy) than ectotherms of the same mass. This means they must hunt and constantly find new food sources to stay alive. Endotherms Slide 205 / 215 Pros: Warm blooded animals never need to warm up. t a moment's notice they can be at maximum metabolism which means they are prepared to hunt or run from predators all the time. These hyenas hunt in packs and defend there hunting territories constantly. They must be on guard for their natural predators, lions or wild dogs. 47 Which of the following is a way an ectotherm might regulate its internal body temperature? Slide 206 / 215 Move into underground burrows to dissipate heat on a hot day hange body color from dark to light when temperatures rise outside Heat from arterial blood warms the cold venous blood returning to the heart Position their bodies to maximize solar radiation in cold climates

85 47 Which of the following is a way an ectotherm might regulate its internal body temperature? Slide 206 (nswer) / 215 Move into underground burrows to dissipate heat on a hot day hange body color from dark to light when temperatures rise outside Heat from arterial blood warms the cold venous blood returning to the heart nswer Position their bodies to maximize solar radiation in cold climates 48 Unlike ectotherms, endotherms Slide 207 / 215 Gain or lose significant amounts of heat by way of the environment re sluggish and have lower metabolic rates in colder temperatures Live in water that stays at a constant temperature Maintain a fairly stable body temperature regardless of external conditions 48 Unlike ectotherms, endotherms Slide 207 (nswer) / 215 Gain or lose significant amounts of heat by way of the environment re sluggish and have lower metabolic rates in colder temperatures Live in water that stays at a constant temperature Maintain a fairly stable body temperature regardless of external conditions nswer

86 49 When comparing a gecko, a dog, and a catfish, who would likely need to consume the most food? Slide 208 / 215 dog gecko catfish when different masses are taken into account, they all require the same amount of food 49 When comparing a gecko, a dog, and a catfish, who would likely need to consume the most food? Slide 208 (nswer) / 215 dog gecko catfish when different masses are taken into account, they all require the same amount of food nswer Ecto v Endo Slide 209 / 215 lion must eat approximately 50 antelopes or other large herbivore per year to maintain his warm blooded metabolism. This much food would sustain 10 cold blooded alligators of the same weight as the lion.