Notes: Cell Processes 1. Movement across cell membrane 2. Photosynthesis 3. Cellular respiration 4. Cell cycle

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1 Notes: Cell Processes 1. Movement across cell membrane 2. Photosynthesis 3. Cellular respiration 4. Cell cycle AMDG 1. Notes: Movement across a cell membrane Cell Membrane-see picture in text book What is the function of the cell membrane? Some substances can pass through while others cannot. Two Types of Transport 1. Passive Transport a. diffusion Osmosis Facilitated diffusion 2. Active Transport a. Transport Protein b. Engulfing 1. (does not require energy) A. - movement from a higher concentration to a lower concentration until equilibrium is reached. WHAT IS EQUILIBRIUM? Equilibrium is reached when concentrations are on either side of a membrane.

2 Diffusion Across Membrane The ability of a molecule to diffuse across a cell membrane depends upon Small Molecules - may diffuse across the membrane. Example: O 2, CO 2, N 2, Type of Molecule-polar or nonpolar Concentration Gradient the amount of substance on either side of membrane 1. - movement of across the cell membrane from higher concentration to lower concentration. Osmosis Vocab _ solute concentration is lower than that inside a cell. Water moves??? solute concentration is higher than that inside a cell. Water moves????? solute concentration equals that inside a cell Water moves???? 2. - movement of substances across the cell membrane from an area of higher concentration to an area of lower concentration with the assistance of _ What type of molecules use Facilitated Diffusion? Large Molecules Example: Glucose, amino acids, nucleotides 2. ( requires energy) Movement from lower concentrations to higher concentrations.

3 A. Usually involves a = cell membrane pump Sodium (Na), Potassium(K), and Calcium(Ca) move across membrane using a transport protein. B. - movement of material inside of the cell. - movement of material out of the cell. 2. Notes: Photosynthesis -photo=light -synthesis=putting together Some Autotrophs capture light energy and store it within organic compounds The Overall Reaction Two Stag Process: 1. 2._ Stage 1. Capture Light Energy Where does this take place? Light Has a like character. Each color corresponds to a certain of light. The the wavelength (blue) the _ the energy the light wave possesses. The the wavelength (red) the the energy the light wave possesses. White Light Light from the sun Made up of a continuous spectrum of waves with different wavelengths

4 How does the cell capture the energy from all of these different wavelengths of light? _ Compound that absorbs light Absorb certain colors more strongly than others Reflect the colors not absorbed = the color you see Chloroplast Pigments - absorbs more red light. Directly involved in light reactions. - absorbs more blue light. Assists chlorophyll a in light reactions = accessory pigment (yellow, orange, brown ) =accessory pigments Why do plants need accessory pigments? Why are plants green? Why do leaves change color in the fall? Stage 2. Use Energy to Make food Overall Equation for Photosynthesis _

5 REACTANTS We captured Light Energy from Sun. Where does CO 2 come from? Where does H 2O come from?_ Stomata PRODUCTS The Carbohydrate produced is broken down by the cell and used for energy, stored, or pieces used to make other molecules such as cellulose Most of the Oxygen produced is released through the stomata back into the environment (21% Earth s atmosphere Rate of Photosynthesis Light intensity Level of Carbon Dioxide Temperature 3. Notes: Cellular Respiration The process of breaking down simple food molecules(glucose) and releasing the energy they contain. All living things undergo cellular respiration The Overall Reaction 2 Stage Process Stage 1- Stage 2- Stage 1. Glycolysis Occurs in the is broken down into 2 smaller molecules A small amount of is released during

6 Stage 2a. Respiration Occurs in The 2 smaller molecules from Stage 1 are broken down even smaller. is released is released A ton of energy is released Stage 2b. Fermentation Occurs in the _ NO Takes the 2 small molecules produced from Glycolysis and breaks them down even smaller. Small amount of energy is released 2 types The Overall Reaction Carbohydrate comes from Breath in _ Breath out Breath out Produces tons of energy in the form your cells can use.

7 4. Notes: Cell Division Key Terms 1. Chromatin 2. Chromosome 3. Chromatid 4. Centromere Tightly coiled chromatin visible during cell reproduction. The DNA in a human chromosome is about 10,000 times the length of the chromosome. Chromosome Structure one of two distinct strands that make up a chromosome. structure that holds the two chromatids. Chromosome Numbers All Human cells EXCEPT sperm and egg cells contain chromosomes 44 chromosomes are non sex chromosomes 2 chromosomes are sex chromosomes Sex Chromosomes = female (in humans) = male (in humans) Sperm/egg=_ chromosomes _ A picture of an individual s chromosomes. The picture arranges the chromosomes in pairs according to similar size, shape, and they carry genes for the same traits Process by which cells produce daughter cells (o spring Differs in prokaryotes and eukaryotes Cell Division in Prokaryotes Cell division _

8 _ division of the nucleus-end result two daughter nuclei containing same number of chromosomes as parent cell(produce body cells) division of nucleus end result four daughter nuclei with half the number of chromosomes as parent cell (to produce sex cells) The Cell Cycle Occurs in Eukaryotic cells Divided into three phases _ 1. Longest phase of the cell cycle Divided into 3 groups Copying DNA Structure of DNA two strands twisted around each other. Think of DNA like a ladder The outer structure is made up of a and (sugar) Rungs of the ladder (inner structure) is made up of connected to each other by bonds (Adenine) (Guanine) A T (Thymine) G C (Cytosine) Who came up with this? 1950s - = X-ray photographs of DNA molecule

9 = interpreted what the photographs meant = DNA structure Replication begins when the DNA is unzipped ( by an enzyme ) This occurs in many different points along the DNA strand A series of _ help to match bases, zip up, and proof read the DNA When replication is complete 2. (M-phase)-refer to textbook for diagrams Division of the nucleus which produces body cells. Divided into four phases Chromatin condenses making chromosomes visible Nucleolus and nuclear membrane disappear Mitotic spindle forms ( looks like a bridge) Fibers move chromosomes to the middle of the cell. During this phase the chromosomes are most visible=karyotypes are taken during this phase of mitosis _ The chromatids of each chromosome separate at the centromere and slowly move toward opposite poles. When the chromatids separate they are considered individual chromosomes

10 _ Opposite of prophase Mitotic spindle disassembles Chromosomes return to a chromatin state Both the nuclear membrane and nucleolus reappears 3. Process by which the cytoplasm divides Animal cells = _ pinches the cell into two cells through the action of microfilaments Plant cells = vesicles of golgi apparatus fuse at midline forming this cell wall. When complete both offspring cell receives: identical copies of the parent cell s chromosomes Half of the parent cell s cytoplasm and organelles How many chromosomes does the parent cell have during prophase? How many chromosomes does each offspring cell have? For both questions assume a human body cell 2. (M-phase) refer to textbook for diagrams Process of nuclear division which produces sex cells ( sperm/egg). Process occurs in reproductive organs (testes and ovaries) Two stages of Meiosis Meiosis I Four phases of Meiosis I Prophase I Same as mitosis

11 may occur (exchange of genetic material) Metaphase I Chromosomes ( still double stranded ) line up in the middle of the cell. Anaphase I Chromosomes ( still double stranded ) move to opposite poles. Telophase I The chromosomes ( still double stranded ) reach the poles Nuclear membrane reforms Cytokinesis I Cytoplasm divides End result after Meiosis I and cytokinesis I Meiosis II The two cells from Meiosis I undergo Meiosis II Four stages of Meiosis II Prophase II Metaphase II Anaphase II Telophase II All four stages of Meiosis II are the same as the stages of Mitosis After= End result Exiting the Cell Cycle Cells exit the cell cycle During this phase cells do not copy DNA or prepare for cell division Many cells in the human body are in this phase. The production of offspring from one parent The offspring are genetically identical to the parent Examples: fission, mitosis, budding Production of offspring through meiosis and the union of a sperm and an egg Offspring are genetically different from parents advantage= enables species to adapt to new conditions

12 Learning Objectives: -Phenomena question: Why does a cell gain or lose mass when placed in different substances? -know all terms/definitions and concept map them -compare/contrast passive vs active transport -I.D. hypotonic, hypertonic and isotonic -Phenomena question: Why do leaves change color in the fall? -What is the main goal of photosynthesis? -know all terms and definitions -know chemical reaction and where the reactants come from and what they are used for. Know all the products and where they come from and what they are used for. -graphs know where photosynthesis takes place in the cell. -phenomena question: why do you get a side cramp while you run? -what is the goal of cellular respiration? -know the reaction: reactants and products=where they come from and what they are used for. -know all terms and definitions - Phenomena question-how do we grow? -know all terms and definitions -# of chromosomes in human cells ( all types) -difference between prokaryotic and eukaryotic cell division -compare/contrast mitosis and meiosis -I.D. Steps of mitosis and meiosis and be able to count the number of chromosomes in each step. -difference between asexual and sexual reproduction know where it occurs in the cell