2017 Pre-AP Biology Semester I Exam study Guide

Transcription

1 2017 Pre-AP Biology Semester I Exam study Guide

2 1 st Law of Thermodynamics: The 1 st Law states that energy can be transferred or transformed but not State the 2 nd Law of Thermodynamics: The 2 nd Law states that every energy transfer or transformation increases the of the universe.

3 16 Laws of Thermodynamics: a. The 1 st Law states that energy can be transferred or transformed but not created or destroyed b. The 2 nd Law states that every energy transfer or transformation increases the disorder (entropy) of the universe.

4 Metabolic Equilibrium Metabolic Disequilibrium Which of the systems above is a closed, which is an open system? 2. What eventually happens in a closed system and what is the result? 3. Give an example of matter that you are exchanging with the environment. 4. Give an example of an energy transformation occurring within your body. 5. What would happen if you became a closed system?

5 Metabolic Equilibrium Metabolic Disequilibrium Which of the systems above is a closed, which is an open system? 1 2. What eventually happens in a closed system and what is the result? Equilibrium, death for organisms 3. Give an example of matter that you are exchanging with the environment. Oxygen in, carbon dioxide out 4. Give an example of an energy transformation occurring within your body. Chemical potential energy of food to heat (and recharged ATP) 5. What would happen if you became a closed system? death

6 Circle the correct choice regarding the diagram above: A molecule is being built/broken down, catabolic/anabolic, endergonic/exergonic, most similar to cellular respiration/photosynthesis.

7 Circle the correct choice regarding the diagram above: a molecule is being built/broken down, catabolic/anabolic, endergonic/exergonic, most similar to cellular respiration/photosynthesis.

8 During a chemical reaction: 1. energy is added 2. Bonds become 3. Bonds 4. Atoms 5. New bonds 6. Matter is

9 During a chemical reaction: 1. Activation energy is added 2. Bonds become unstable 3. Bonds break 4. Atoms rearrange 5. New bonds form 6. Matter is conserved

10 1. Which number represents the amount of activation energy required without an enzyme? 2. With an enzyme? 3. Summarize the effect of an enzyme on activation energy? reactants products

11 1. Which number represents the amount of activation energy required without an enzyme? 3 2. With an enzyme? 2 3. Summarize the effect of an enzyme on activation energy? Lowers it reactants products

12 1. Describe what is being shown in the diagram: 2. Name the process

13 1. Describe what is being shown in the diagram: A molecule of water is lost as a monomer is added to a polymer 2. Name the process dehydration synthesis

14 1. Describe what is being shown in the diagram: 2. Name the process

15 1. Describe what is being shown in the diagram: A molecule of water is added to break a monomer from a polymer 2. Name the process hydrolysis

16 Use complete sentences and the terms 1-7 (below) to describe the steps in the enzyme-cycle: 1 Enzyme 2 Active site 3 Substrate 4 Induced fit 5 H 2 O molecule 6 Hydrolysis 7 Products

17 Enzyme-Cycle Diagram

18 C D B A Describe and explain the rate at A D And, what was the Vmax you calculated for the graph?

19 Slow rate due to lag-time substrate must get into liver cells Rate zero because ran out of substrate Rate slows as substrate starts to run out Highest rate is between 5 and 20 min. because substrate is abundant: 17.3 µmol/ml min. (c)

20 1. Maximum rate (steepest slope) 1 10 s = 2. Rate 40 to 50 s = 3. Why the difference in rate 0 10 s vs s? 4. Change to maintain initial high rate: 5. Effect of doubling enzyme on rate:

21 1. Maximum rate (steepest slope) 1 10 s = 0.7 moles/second 2. Rate 40 to 50 s = 0 moles/second 3. Why the difference in rate 0 10 s vs s? 0 10 s = abundant substrate = substrate ran out 4. Change to maintain initial high rate: Add more substrate 5. Effect of doubling enzyme on rate:

22 Describe and explain the relationship between temperature and enzymatic reaction rate:

23

24 1. Identify the optimal temperature for most human enzymes? How does this compare with body temp.? 2. Identify the optimal temperature for enzymes from thermophilic bacteria? 3. Explain why the optimal temperatures are different for these two species:

25 1. Identify the optimal temperature for most human enzymes? How does this compare with body temp.? 37⁰C about the same 2. Identify the optimal temperature for enzymes from thermophilic bacteria? 78⁰C 3. Explain why the optimal temperatures are different for these two species: Human enzymes best adapted for our body-temperature while thermophilic bacteria live in hot-springs so their enzymes have evolved through natural selection to function at high temperature.

26 ph above or below optimal will break Hydrogen and ionic bonds, causing enzyme to denature. 1. Why is the 3-D structure of an enzyme important to its function? 2. Why can ph above or below an enzyme s optimal change the enzyme s structure? 3. How does denaturation affect an enzyme s function & rate of reaction?

27 ph above or below optimal will break Hydrogen and ionic bonds, causing enzyme to denature. 1. Why is the 3-D structure of an enzyme important to its function? Enzyme s must have a lock-key-fit with their substrate to interact with it 2. Why can ph above or below an enzyme s optimal change the enzyme s structure? Bonds that hold the enzyme s 3-D shape together can break 3. How does denaturation affect an enzyme s function & rate of reaction? When an enzyme denatures, it unravels, and its lock-key-shape is lost and it can not connect with its substrate, so it loses function.

28 1. Identify the optimal ph for pepsin? 2. Infer what the ph of the stomach is likely to be: 3. Identify the optimal ph for trypsin: 4. Infer what the ph of the small intestine is likely to be: 5. Explain why the optimal ph is different for the 2 enzymes:

29 1. Identify the optimal ph for pepsin? Infer what the ph of the stomach is likely to be: acidic: Identify the optimal ph for trypsin: 8 4. Infer what the ph of the small intestine is likely to be: slightly basic: 8 5. Explain why the optimal ph is different for the 2 enzymes: the enzymes have adaptations to be most effective in the phenvironment in which they are found

30 1. What is the function of the mitochondrion? 2. Describe the structure of the mitochondrion:

31 1. What is the function of the mitochondrion? It is the powerhouse of the cell (it recycles ATP energy). 2. Describe the structure of the mitochondrion: It is composed of two membranes (outer and highly folded inner membranes).

32 The diagram on the left is a zoomed-in view across the inner mitochondrial membrane. ATP Synthase 1. Where is there a higher [H+]? 2. Which direction will [H+] naturally diffuse? 3. How do [H+] cross the membrane? 4. What happens as they do? 5. How does the mitochondrion recycle/recharge ATP energy?

33 The diagram on the left is a zoomed-in view across the inner mitochondrial membrane. ATP Synthase 1. Where is there a higher [H+]? Intermembrane space 2. Which direction will [H+] naturally diffuse? From the intermembrane space into the matrix 3. How do [H+] cross the membrane? Through ATP synthase 4. What happens as they do? It spins like a rotor 5. How does the mitochondrion recycle/recharge ATP energy? The energy in the [H]+ gradient is used to recycle/recharge ATP

34 1. Energy enters Earth s ecosystems as. 2. Photosynthesis converts CO 2 and H 2 O into, a form of energy 3. Respiration breaks down to recharge ATP and releases energy as.

35 1. Energy enters Earth s ecosystems as light. 2. Photosynthesis converts CO 2 and H 2 O into organic molecules, a form of chemical potential energy 3. Respiration breaks down organic molecules to recharge ATP and releases energy as heat.

36 enzymes enzymes Most of the matter/mass from weight-loss is in the form of CO 2 Most of the matter/mass acorn oak tree is in the form of CO 2

37 enzymes enzymes 1. List three similarities between the two reactions: 2. Describe two differences:

38 enzymes enzymes 1. List three similarities between the two reactions: both use glucose, oxygen, and carbon dioxide, enzymes are used, energy is transformed 2. Describe two differences: The reactants and products are switched, photosynthesis is endergonic while respiration is exergonic

39 1. Where does the mass come from for: acorn mature oak tree? 2. Where does the mass go when a person loses weight?

40 1. Where does the mass come from for: acorn mature oak tree? Most of the mass comes from CO 2, a smaller amount comes from the H that were removed from H 2 O 2. Where does the mass go when a person loses weight? Most of the mas is exhaled as CO 2 gas and some is excreted as H 2 O

41 Discuss the role of process I and II in the cycling of carbon:

42 Process I: Photosynthesis removes CO 2 from the atmosphere and uses light energy to convert it into organic molecules (chemical potential energy of glucose). Process II: Cellular respiration breaks down organic molecules, releasing energy to recycle ATP and releasing CO 2 back into the atmosphere

43 A student performed the experiment below to explore the effect of plant and animals on the carbon cycle. The student placed water with a neutral ph of 7 in each beaker at the start of the investigation. When CO 2 dissolves in water, it forms a weak acid. A the lower the ph of a solution, the more acidic it is. Based on this information, predict (and justify) how the ph of each beaker will change over the course of the investigation.

44 A student performed the experiment below to explore the effect of plant and animals on the carbon cycle. The student placed water with a neutral ph of 7 in each beaker at the start of the investigation. When CO 2 dissolves in water, it forms a weak acid. A the lower the ph of a solution, the more acidic it is. Based on this information, predict (and justify) how the ph of each beaker will change over the course of the investigation. I = more basic (higher ph), with light photosynthesis will remove CO2 II = more acidic (lower ph), without light plants will produce CO2 (resp.) III & IV = more acidic (lower ph), animals perform only cellular respiration (producing CO2) V and VI = controls, ph expected to stay around 7

45 Summarize the pattern in average global CO 2 concentration from 1990 to 2010

46 Summarize the pattern in average global CO 2 concentration from 1990 to 2010 The average increased from 1990 to 2000 and then again from 2000 to 2010

47 1. Energy enters Earth s ecosystems as and exits as. 2. Energy through Earth s ecosystems. 3. Matter through Earth s ecosystems aided by the action of organisms called.

48 1. Energy enters Earth s ecosystems as _light_ and exits as _heat. 2. Energy _flows_ through Earth s ecosystems. 3. Matter _cycles_ through Earth s ecosystems aided by the action of organisms called detritivores.

49 1. Name the primary producer 2. Name a primary consumer 3. Name a secondary consumer 4. What affect would a reduction in light have on this food web? 5. Explain your answer to #4

50 1. Name the primary producer phytoplankton 2. Name a primary consumer zooplankton 3. Name a secondary consumer squid 4. What affect would a reduction in light have on this food web? Decrease abundance at all levels 5. Explain your answer to #4 light is energy entering food web, necessary for photosynthesis

51 Given a food-web, how would you correctly identify a: producer, strict herbivore, strict carnivore, and omnivore?

52 Given a food-web, how would you correctly identify a: producer, strict herbivore, strict carnivore, and omnivore? H, I, F, and G are strict carnivores C & D are strict herbivores E is an omnivore A & B are producers such as plants

53 What percentage of the energy in plants makes it into the bodies of (show set-up and circle the final answer): a. Primary consumers b. Secondary consumers c. Tertiary consumers

54 Pyramid of Net Production a. What % of energy in plants makes it to primary consumers? 1,000/10,000 = 1/10 = 10 % b. What % of energy in plants makes it to secondary consumers? 100/10,000 = 1/100 = 1 % c. What % of energy in plants makes it to tertiary consumers? 10/10,000 = 1/1000 = 0.1%

55 Describe the rate of growth for I, II, III, and IV of the logistic model of population growth:

56 Describe and explain the logistic model of population growth: Red = growth starts exponential Blue = growth slows as density-dependent factors such as competition for resources limits growth; dashed line = carrying capacity

57 3. a. Calculate the mean rate of growth from day 5 to 10. Record your answer to the nearest whole #. b. What is the carrying capacity? c. How would this species growth curve be affected if it was grown with a second species with which it was in competition with? d. with which it was not in competition with?

58 3. a. Calculate the mean rate of growth from day 5 to 10. Record your answer to the nearest whole #. Slope, rise/run = approx. 90 ml/day b. What is the carrying capacity? Approx. 900 c. How would this species growth curve be affected if it was grown with a second species with which it was in competition with? Carrying capacity would be lower d. with which it was not in competition with? unchanged

59 Mean Rapid Radish Height (cm) Plant Population 1. What is the mean height and standard error for population 1? 2. For population 2? 3. Is it likely that the two populations have a statistically significantly different height? 4. Justify your answer to #3: 5. What is the best method to decrease the size of the 2 x SEM bars?

60 Mean Rapid Radish Height (cm) Plant Population 1. What is the mean height and standard error for population 1? 8 ±1 2. For population 2? 12 ±1 3. Is it likely that the two populations have a statistically significantly different height? Yes, the standard error bars do not overlap 4. What is the best method to decrease the size of the 2 x SEM bars? Increase the sample size, since to calculate SEM you take the standard deviation divided by the square root of the sample size

61 1. Name & describe two structural features of the leaf that are designed to reduce a plant s water-loss: 2. What is the function of a terrestrial plant s roots? Stoma 3. What is the function of plant s xylem? 4. When a leaf is in the light, and its stomata are open, in which direction are the following moving through the stomata: H 2 O, CO 2, O 2?

62 1. Name & describe two structural features of the leaf that are designed to reduce a plant s water-loss: waxy cuticle and stomata 2. What is the function of a terrestrial plant s roots? Absorb water from soil Stoma 3. What is the function of plant s xylem? Transport water through plant tissues 4. When a leaf is in the light, and its stomata are open, in which direction are the following moving through the stomata: H 2 O, CO 2, O 2? CO 2 in and H 2 O and O 2 out

63 Cubes of agar with a pink ph indicator are placed into vinegar solution. The cubes will turn clear as vinegar diffuses into the agar. 1. Which of the cubes above will experience a complete color-change first? 2. Explain your selection:

64 Cubes of agar with a pink ph indicator are placed into vinegar solution. The cubes will turn clear as vinegar diffuses into the agar. Which of the cubes above will experience a complete color-change first? The smallest cube Explain your selection: The smallest cube would have the largest S.A.:V. and thus would be most efficient at diffusion

65 Verbally discuss: 1. What is the independent variable? 1. What is the dependent variable? 2. What sucrose concentration (M) would be isotonic to the potato tissue?

66 1. What is the independent variable? [sugar] (M) 2. What is the dependent variable? % change in mass 3. What sucrose concentration (M) would be isotonic to the potato tissue? Between 1 and 2 M

67 1. What scientific question is this investigation deigned to test? 2. Which choice-chamber represents the control-chamber? 3. What is the purpose of the control-chamber in this investigation?

68 1. What scientific question is this investigation deigned to test? Do pillbugs have a preference for a wet or dry environment? 2. Which choice-chamber represents the control-chamber? B 3. What is the purpose of the control-chamber in this investigation? To check whether there are any hidden variables affecting the results of the wet versus dry treatment. For example, there may be more light on one side of the choice-chambers that might affect pillbug distribution across the choice-chamber.

69 Dark-side # of Pillbugs Light-side # of Pillbugs 1. What is the null hypothesis for this experiment? 2. The chi-square value is 1.2. Do you reject or fail to reject the null hypothesis?

70 Dark-side # of Pillbugs Light-side # of Pillbugs (12-15) 2 + (18-15) 2 = The null hypothesis is that pillbugs show no preference for a light versus dark environment. The chi-squared value of 1.2 is less than the critical value of 3.84 for P=0.05 and 1 degree of freedom, thus we fail to reject the null hypothesis (pillbugs do not have preference for dark versus light).

71 a. What is the independent variable? b. What is the dependent variable? c. What are two variables that are controlled? d. Pose a scientific question that this study could be designed to answer:

72 a. What is the independent variable: number of fish b. What is the dependent variable: fish behavior c. What are two variables that are controlled: temperature, light d. Pose a scientific question that this study could be designed to answer: What is the effect of fish density (number of fish per unit area) on fish behavior?

73 1. Why is this design unable to answer the farmer s original questions? 2. Show a design that could work to answer both questions:

74 1. The farmer is manipulating two variables at once he can not say whether it is the soil type (A versus B) or fertilizer type (X versus Y) or a combination of both that is having the effects seen in the two fields. 2. See below: A & X B & X A & Y B & Y