Bio Exam 2

whether a molecule can cross the plasma membrane depends on

- Size of molecule - Shape of molecule - Chemical properties of molecule - The charge of the molecule

complete oxidation of glucose results in ___ ATP molecules

36-38

Which substrate is missing: 6CO2+_____ +energy = C6H12O6 + 6O2

6H2O

which of the following substrates is essential to an organism that utilizes photosynthesis

6H2O

exergonic reaction

A chemical reaction that releases energy

which statement is not true about how various conditions will affect the activity of an enzyme

An enzyme's activity is generally reduced by an increase in substrate concentration.

If plants were no longer able to perform the light reactions and they could only utilize the Calvin cycle, which of the following would be true? Select all that apply. A) Plants would not produce oxygen. B) G3P would be produced in much smaller quantities. C) NADPH production would decrease while ATP production increased. D) G3P would be produced in much greater quantities.

Answer: B, C, D

which of the following is a true statement about enzyme inhibition

In competitive inhibition, the inhibitor binds to the active site of the enzyme. In noncompetitive inhibition, the inhibitor binds to the allosteric site of the enzyme. In irreversible inhibition, a poison binds to the enzyme so that it can never work again. Most inhibitors act in a reversible fashion.

which type of molecule will not diffuse directly across the cell membrane without the help of transport proteins

Na+

binary fission in bacteria differs from mitosis because

The chromosome copies attach to the plasma membrane and are pulled apart by cell growth, the chromosome is a simple DNA strand without complex proteins and no spindle forms, and there is no nuclear membrane to break down and rebuild

which of the following is an example of active transport through a cell membrane

The movement of chlorine ions from an area of low concentration on one side of the membrane to an area of high concentration on the other side of the membrane.

which is the best definition of osmosis

The movement of water across a semi permeable membrane from an area of higher water concentration to an area of lower water concentration.

if a living plant were moved from a freshwater aquarium to a saltwater aquarium what would occur

The plant's cells would lose water and plasmolysis would occur.

which if the following is not a form of potential energy

a muscle contracting

Some desert beetles can live out their life without ever drinking liquid water. They survive on "metabolic water," which

is water formed during the electron transport chain

the amount leaving the cell and entering the cell is the same

isotonic

which form of energy is not correctly associated with the related example

kinetic energy: fat molecules

which is the best definition of active transport

movement of a substance against its concentration through the release of energy from ATP

why can nonpolar molecules freely cross the cell membrane while polar molecules require energy

nonpolar molecules tend to be molecules that are similar in composition to the phospholipid center of the membrane. they can cross the membrane at no energy cost

interphase

occupies the majority of the cell cycle includes G1, S, and G2 stages results in an increase in cell size

proteins in a membrane are

peripheral if they are on the inside surface held in place by the cytoskeleton. integral if they are embedded in the membrane and protrude from either surfaces of the bilayer.

in a phospholipid bilayer the

phosphate heads are oriented toward the exterior of the cell or toward the cytoplasm.

oxygen production in photosynthesis involves which of the following

photosystem II splitting of water light reactions

which sequence of the mitotic stages is correct

prophase, prometaphase, metaphase, anaphase, telophase

Acetyl-CoA is produced from

pyruvate and CoA

the preparatory reaction converts

pyruvates into acetyl-CoA and carbon dioxide.

active transport

requires an input of ATP

The activity of an enzyme might be increased by all of the following except

the presence of other enzymes

explain why the head of one phospholipid would never be found pointing to the tail of another phospholipid

the tails of a phospholipid are hydrophobic and the heads are hydrophilic

Fermentation follows glycolysis in some cells when oxygen is not available. True False

true

The first event in the Calvin cycle is the attachment of carbon dioxide to the five-carbon RuBP molecule, which: forms a six-carbon molecule that immediately breaks down into two three-carbon PGA molecules. True False

true

in order to roll a rock down a hillside, you must first push it up the hill. pushing the rock is analogous to the energy of an activation of a chemical reaction

true

the breakdown of glucose in cellular respiration is a catabolic reaction

true

compared with other components found in a plant cell such as the cell membrane, the chloroplasts or the nucleus, the mitochondria would be the only one that would

use significant amounts of oxygen to produce ATP.

coupling occurs when the energy released by an exergonic reaction is

used to drive an endergonic reaction

which of these processes occurs in the cytosol

glycolysis

freshwater protozoans react to a/an ____ environment by removing water through _____.

hypotonic; a contractile vacuole

product of photsynthesis, is the cheif source of energy for most organisms

glucose

What are the end products of photosynthesis?

glucose and oxygen

which of the following substrates are required for cellular respiration

glucose and oxygen

The first phase of cellular respiration is

glycolysis

what would happen if a drug directly interfered with the functioning of RuBP carboxylase

Carbon dioxide would not be fixed to RuBP, stalling the Calvin cycle.

during the light reactions, what structure is responsible for absorbing the solar energy

Chloroplast

which statement is true about the plasma membrane

Proteins and phospholipids can move sideways within the plane of the membrane.

endergonic reaction

Reaction that absorbs free energy from its surroundings.

the fixation of carbon dioxide in the first step of the calvin cycle is facilitated by which enzyme

RuBP carboxylase

what type of transport mechanism is required to move sodium ions against their concentration gradient

active

Cancer cells require many nutrients, which are supplied by blood vessels. The growth of new blood vessels to cancerous tissue is called:

angiogenesis

if there are twelve different intermediate products produced in the stages of a metabolic pathway within a cell, we can expect that there

are about twelve enzymes, at least one responsible for each step in the metabolic pathway.

endergonic reactions

can only occur if there is an input of energy

which is most closely associated with the calvin cycle

carbon dioxide fixation

what would happen if the stomata of a league remained closed all day

carbon dioxide in the air spaces of the leaf would decrease the amount of water within the air spaces would decrease the

The component of an animal cell membrane of an animal cell membrane that regulates the fluidity by stiffening the membrane at higher temps and preventing the membrane from freezing

cholesterol, lipid, steroid (all are correct)

the majority of the carbon dioxide we exhale is produced in

citric acid cycle

the final electron acceptor in glycolysis is oxygen and this step will occur within the matrix of the mitochondria

false

the light dependent reactions of photosynthesis occur in the stroma of the chloroplast

false

which processes produces alcohol or lactate

fermentation

angiogenesis

formation of new blood vessels into the tumor, is directed by additional mutations in tumor cells, brings nutrients and oxygen to a tumor