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