Module 5

. Red blood cells do not contain mitochondria. With your current knowledge of cellular respiration, can red blood cells break down glucose? Explain.

. Yes, they do it in the cytoplasm.

. electron transport chain

. a series of electron-carrying molecules within a membrane that transfer electrons and release energy at each transfer

. What are the products of the light reactions? What is considered waste and what moves on to the Calvin cycle?

. The light reactions create ATP and NADPH, which go to the Calvin cycle, and six O2 molecules as waste.

. What is the benefit of the pigments in photosynthesis?

. The pigments absorb the light energy needed to start photosynthesis.

. How is the design of the chloroplast suited to its function?

. The stacks of thylakoids increases the membrane surface area for the light reactions (ETC) to take place.

. Krebs cycle

. The stage of cellular respiration where carbon dioxide is used to complete the breakdown of pyruvic acid molecules, releasing energy

. phosphorylation

. The transfer of energy when a phosphate group is moved between molecules

. anaerobic

. Without oxygen

. fermentation

. A cellular process producing ATP without oxygen.

. photosystem

. A cluster of chlorophyll and other molecules in the thylakoid membrane that absorbs light energy

. chlorophyll

. A group of pigments (mostly composed of chlorophyll a and chlorophyll b) found in algae, green plants, and cyanobacteria. It is necessary for photosynthesis, allowing for the absorption of energy from light.

. Explain how the structure of a leaf is designed perfectly for photosynthesis.

. A leaf has mesophyll cells positioned so that the top cells have the most chlorophyll. Stomata allow for gas exchange.

. If you wanted to grow plants in a room with no windows, what colors of light would you choose to shine of the plants to maximize their photosynthetic potential? Why?

. All colors but especially blue and red as these colors are absorbed white green light is reflected.

. Why can we say that most life of Earth is powered by the sun?

. Almost all life either is a plant or eats plants (or eats organisms that eat plants) and plants get their energy from the sun.

. pigment

. An organic compound that reflects specific light wavelengths producing color

. Compare the two types of fermentation.

. Both lactic acid fermentation and alcoholic fermentation break down glucose without oxygen. Lactic acid fermentation is performed in microorganisms and some animal cells while alcoholic fermentation is performed in mostly yeast cells. The waste product of lactic acid fermentation is lactic acid and the waste products of alcoholic fermentation are ethyl alcohol and carbon dioxide.

. thylakoid

. Disk-shaped sac suspended in the stroma of chloroplasts. It is the site of the light reactions of photosynthesis.

. stroma

. Gel-like fluid found inside the inner membrane of a chloroplast

. If a plant cell needs energy for endocytosis, what does it use and where does the energy come from?

. It uses ATP, which comes from cellular respiration.

. Would you expect a plant to grow well in only green light? Explain.

. No. Green light is reflected, not absorbed, so the plant would be malnourished.

. aerobic

. Requiring oxygen

. List four foods made by fermentation.

. Sourdough, sauerkraut, soy sauce, cheese.

. grana

. Stacks of thylakoids

. glycolysis

. The first stage of cellular respiration where glucose is split in half. Glyco- means having to do with sugar, and ¬-lysis means breakdown.

. How is the design of the mitochondrion suited to its function?

. The folded membrane provides lots of room for light reactions.

. Why is ATP better suited to provide the energy for cellular activities than glucose?

A. Glucose is too large for "everyday use." It better serves to store energy.

. What is the net gain of ATP in each stage of cellular respiration?

A. Glycolysis - 2 ATP, link reaction - 0, Krebs cycle - 2 ATP, ETC - 34 ATP.

. How is ATP made during fermentation?

A. Glycolysis without oxygen

. Where is energy stored in ATP?

A. It is stored in the bonds between the phosphate groups.

. What is the function of NADPH?

A. NADPH carries energy-rich electrons to the Calvin cycle where it drops off the electrons to be used in making glucose.

. Describe how ATP is generated in the light reactions.

A. When light hits PS 2, the excited electrons are carried down the ETC, releasing energy along the way, which is used to pump H+ ions into the thylakoid space. (The electrons from PS 2 are replaced by the H+ ions and water split into oxygen gas and hydrogen.) When the electrons are again excited by PS 1, they cause NADP to become NADPH, which moves on to the Calvin cycle. The H+ ions in the thylakoid space diffused through the membrane, spinning ATP synthase. This movement brings ADP and P closed enough together to allow ATP to form.

. Compare photosynthesis and cellular respiration by completing the following table:

Photosynthesis Cellular Respiration Function Converts lights to chemical energy (glucose) Breaks down glucose, releasing energy and converting it to TP Type of cell Plant cells and some algae Animal and plant cells Location Thylakoid membrane and stroma Cytoplasm, mitochondrial matrix, and mitochondrial membrane. Reactants Carbon dioxide, water, light Glucose (C6H12O6) and O2 Products Glucose and oxygen CO2, water, and ATP Electron carrier molecules NADPH NADPH and FADH2 Final electron acceptor of ETC Oxygen NADPH Is ATP synthase used to produce ATP? If so, where? Yes, in the ETC of the light reactions Yes, in the ETC Equation 6 CO2 + 6 H2O + light = C6H12O6 + 6 O2 C6H12O6 + 6 O2 = 6 CO2+ 6 H2O + ATP