Biology Exam III 2
Terms
undefined, object
copy deck
- An electron carrier that is used in harvesting energy from glucose molecules in a series of gradual steps in the cytoplasm is
- NAD+
- In eukaryotes, the glycolytic reactions take place in the
- cytoplasm of the cell
- In the absence of oxygen, hydrogen atoms generated by glycolysis are donated to organic molecules in a process called
- fermentation
- Chemiosmotic generation of ATP is driven by
- a difference in H+ concentration on the two sides of the mitochondrial membrane
- The reaction, C6H6O6 + 6O2 = 6 CO2 + 6 H2O, when it occurs in living cells is known as
- aerobic respiration
-
In oxidative respiration, energy is harvested from glucose molecules in a sequence of four major pathways. Which of the following is not one of these four pathways?
Krebs cycle
Glycolysis
Beta Oxidation
Pyruvate Oxidation
- Beta Oxidation
- In which of the following steps of glycolysis, 2 ATP molecules are required?
- Glucose priming
- A process common to all living organisms, aerobic and anaerobic, is
- glycolysis
- When ATP levels are high, acetylCoA is channeled into
- fatty acid biosynthesis
- A single glucose molecule can drive the Krebs cycle
- two turns
- The coenzyme electron carriers produced in the Krebs cycle are
- FADH2 and NADH
- Regardless of the electron or hydrogen acceptor used, one of the products of fermentation is always
- NAD+
- A biochemist wants to control the initial substrate-level phosphorylation that occurs in the tracheal cells of grasshoppers once glucose has crossed the plasma membrane. This means that he will
- have to prevent glycolysis from occurring in the cytoplasm
- What is the correct sequence concerning glucose catabolism?
- glycolysis - Pyruvate - Acetyl CoA - Krebs Cycle - Electron Transport Chain
- The Krebs Cycle occurs in the mitochondria. There are nine biochemical reactions involved in the Kreb cycle, and they are highly ordered. What is the correct order that they occur in?
- acetyl-CoA joins the Krebs cycle and unites with oxaloacetate - forming citrate - which forms alpha-ketoglutarate - which forms succinylCoA - which forms succinate - which forms fumarate - which forms malate - which forms oxaloacetate
- In cellular respiration, energy-depleted electrons are donated to an inorganic molecule. In fermentation, what molecule accepts these electrons?
- an organic molecule
- Which of the following is not a stage of aerobic respiration?
- glycolysis
- Which steps in glycolysis require the input of energy?
- the glucose priming steps, the phosphorylation of glucose, and the phosphorylation of fructose 6-phosphate
-
Pyruvate dehydrogenase is a multienzyme complex that catalyzes a series of reactions. Which of the following is not carried out by pyruvate dehydrogenase?
a decarboxylation reaction
the production of ATP
producing an acetyl group from pyru - the production of ATP
- How many molecules of CO2 are produced for each molecule of glucose that passes through glycolysis and the Krebs cycle?
- 6
- The electrons generated from the Krebs cycle are transferred to ____________ and then are shuttled to _______________.
- NAD+ / electron transport chain
- The electron transport chain pumps protons
- out of the mitochondrial matrix.
- What process of cellular respiration generates the most ATP?
- chemiosmosis
- Oxidizing which of the following substances yields the most energy?
- fatty acids
- The final electron acceptor in lactic acid fermentation is:
- pyruvate
- Most plants incorporate carbon dioxide into sugars by means of a cycle of reactions called the
- Calvin cycle
- Flattened sacs of internal membranes which have proteins embedded and are associated with photosynthesis are called
- thylakoids
- In green plant photosynthesis, the electron donor for the light dependent reaction is
- water
- In the dark reactions of photosynthesis, CO2 is added to a five-carbon sugar-phosphate known as
- RuBP
- Light consists of units of energy called
- photons
- Visible light has a wavelength range of
- 400-740 nanometers
- Molecules that absorb light are called
- pigments
- The photosystem channels the excitation energy gathered by absorption of light by any one of the pigment molecules to a specific “reaction center chlorophyll,†which in turn passes the energy to
- the primary electron acceptor
- Which of the following is common to both cellular respiration and the light reactions of photosynthesis?
- the chemiosmotic formation of ATP
- In the photosystem I photocenter, light energy captured by pigment molecules is passed on to a special molecule called
- P700
- Photosystem II differs from photosystem I in that the following molecule is not made directly from the process
- NADPH
- In dark reactions, when CO2 is added to a molecule of RUBP the product is
- phosphoglycerate
- How many revolutions of the Calvin cycle are required to produce the sugar glucose?
- 6
- Which part of the chloroplasts contain the Calvin-cycle enzymes?
- stroma
- In the plants that utilize the CAM pathway, what happens to the stomata?
- The stomata open in the evening but close in the morning.
- Within chloroplasts, the semiliquid matrix in which the Calvin cycle occurs is called:
- stroma
- Visible light occupies what part of the electromagnetic spectrum?
- a small portion in the middle
- The colors of light that are most effective for photosynthesis are
- red, blue, and violet.
- A photosystem consists of
- a group of chlorophyll molecules held together by proteins.
- Which photosystem is believed to have evolved first?
- cyclic photophosphorylation
- Oxygen is produced during photosynthesis when
- water molecules are split to provide electrons for photosystem II.
- During photosynthesis, ATP molecules are generated by
- chemiosmosis.
- The overall purpose of the Calvin cycle is to:
- build organic (carbon) molecules.
- The final product of the Calvin cycle is
- G3P.
- C4 photosynthesis is an adaptation to hot, dry conditions in which
- CO2 is fixed and stored in the leaf.