Final Flashcards
The process of photosynthesis results in the formation of two substances essential to our existence:
sugar and oxygen.
Life existed on Earth as early as ______ years ago.
3 to 4 billion
Which of the following statements about stromatolites is FALSE?
They are fossil structures, with none alive today.
On Mars, there is evidence for the presence of water in the form of______.
ice, liquid water and snow
Which of the following statements about proteinoid microspheres is FALSE?
They are thought to be the first forms of life.
Which of the following statements concerning primitive cells is FALSE?
They constructed new cells from organic molecules made via photosynthesis.
A heterotroph:
is exemplified by a fungus.
Which of the following statements about photosynthetic autotrophs is FALSE?
They obtain their required organic compounds from external sources.
Which of the following statements concerning the earliest photosynthetic organisms is FALSE?
They have been found in rocks 4 billion years old.
The oxygen gas released in photosynthesis originates from:
water.
Atmospheric levels of oxygen gas approached modern levels approximately ______ years ago.
500 million
Ozone in the outer layer of the atmosphere has important consequences for living things in that it:
absorbs ultraviolet rays from sunlight.
Respiration refers to the process by which organisms:
break down molecules under aerobic conditions.
Prokaryotic cells differ from eukaryotic cells in that prokaryotic cells:
lack a nuclear envelope.
Which are prokaryotic organisms?
cyanobacteria and archaea
The first cells on Earth were most likely:
archaeans.
Which of the following is NOT an adaptation of photosynthetic organisms to rocky coasts?
pigment systems
The function of the cuticle is:
retarding water loss.
The function of stomata is:
regulating the exchange of gases.
Which of the following statements concerning stomata is FALSE?.
They form a waxy covering on all aboveground portions of the plant.
In perennials, the ______ is most similar in function to the cuticle-covered epidermis of annuals.
cork
Water is transported upward through the plant body in the:
xylem.
The food manufactured by photosynthesis is transported throughout the plant body in the:
phloem.
The function of phloem is to ______.
transport food
If a plant is a vascular plant, then by definition that plant must contain ______.
phloem
Secondary growth refers to growth:
originating from lateral meristems.
The activity of the ______ results in a thickening of stems, branches, and roots.
lateral meristems
A seed is composed of three parts:
seed coat, embryo, and food supply.
Natural communities of organisms of wide extent, characterized by distinctive, climatically controlled groups of plants and animals, are called:
biomes
What organisms are found at the base of productivity in almost all ecosystems?
photosynthetic bacteria, algae, and plants only
In all ecosystems, heterotrophs are completely dependent on the productivity of all the following groups of organisms EXCEPT:
animals.
Humans first appeared about ______ years ago.
2 million
The development of agriculture started at least ______ years ago.
10,000
Cytology is the study of:
cell structure, function, and life histories.
The projected human population of the Earth by 2050 is _____ billion.
9
The greenhouse effect refers to the:
trapping of heat radiated from Earth.
Phytoremediation refers to the process by which plants:
clean up polluted environments.
Which substance makes up more than half of all living matter and more than 90 percent of the weight of most plant tissues?
Water
The most abundant organic molecules in nature are:
carbohydrates.
_________ is a monosaccharide, and ______________ is a disaccharide.
Fructose; lactose
________ is composed of two sugar subunits linked covalently.
Sucrose
The common transport form of sugar in plants is ______ and in animals is ______.
sucrose; glucose
The formation of ______ from ______ occurs by dehydration synthesis.
sucrose; glucose and fructose
Which of the following statements about hydrolysis reactions is FALSE?
They are a type of condensation reaction.
The principal polysaccharide in the plant cell wall is:
cellulose.
What is the most abundant organic compound known?
cellulose
Which of the following consists of beta-glucose subunits?
cellulose
The matrix of the plant cell wall contains:
pectins and hemicelluloses.
Which stabilize the cell wall by forming hydrogen bonds with it?
hemicelluloses
Which comprise most of the middle lamella?
pectins
The principal component of the cell walls of fungi is:
chitin.
The monomer of ___________ is N-acetylglucoseamine.
chitin
When an oil undergoes hydrolysis, the products are:
1 glycerol and 3 fatty acids
Which are examples of triglycerides?
oils and fats
A fat differs from a phospholipid in that a fat contains:
3 fatty acids
The main function of cutin and suberin is to:
prevent water loss.
Which lipid is a major component of cork cell walls?
suberin
Who am I? I give cell walls a lamellar appearance?
suberin
The most water-repellant of the lipids are:
waxes
Which of the following is characterized by the presence of four interconnected hydrocarbon rings?
steroids
In all organisms except prokaryotes, an important role of sterols is to:
stabilize the phospholipid tails in cell membranes.
The monomers of proteins are:
amino acids.
How many different kinds of amino acids are used to build proteins?
20
A peptide bond occurs between the ______ groups of adjacent amino acids in polypeptides.
amino and carboxyl
When a polypeptide undergoes hydrolysis, the products are:
amino acids
The linear sequence of amino acids is called the ______ structure of a protein.
primary
A common ______ structure of proteins involves a hydrogen bond between the amino group of one amino acid and the carboxyl group of an amino acid farther along the peptide chain.
secondary
The tertiary structure of a protein is a result of all of the following EXCEPT:
interactions between two or more polypeptide chains.
The ______ structure of a protein involves interactions between two or more polypeptide chains
quaternary
Which of the following statements about enzymes is FALSE?
They are typically effective only at high concentrations.
Nucleic acids are different from proteins in that nucleic acids contain:
phosphorus.
The monomers of nucleic acids are:
nucleotides.
The subunits of a nucleotide are a(n):
five-carbon sugar, a nitrogenous base, and a phosphate group.
When many nucleotides undergo dehydration synthesis, the product(s) is(are):
a nucleic acid
Adenosine triphosphate is a type of:
nucleotide.
The principal role of ATP in the cell is:
providing energy.
Which of the following statements about secondary metabolites is FALSE?
They are found in all cells of a plant.
Which of the following is a primary metabolite?
glucose
The major classes of secondary plant metabolites are:
alkaloids, phenolics, and terpenoids.
______ is an alkaloid used to dilate pupils in eye examinations.
Atropine
Who am I? I form a “blanket” that stabilizes photosynthetic membranes and thus helps the plant cope with heat.
isoprene.
Essential oils are types of:
terpenoids.
Which of the following secondary metabolites consists of isoprene units?
taxol
The largest group of plant phenolics are the:
flavonoids.
______ is a secondary metabolite responsible for adding compressive strength, stiffness, and waterproofing to the plant cell wall.
Lignin
_______first concluded that all cells arise from preexisting cells.
Rudolf Virchow
Eukaryotic cells differ from prokaryotic cells in that eukaryotic cells have:
a nucleus
Cyclosis refers to:
the constant streaming of the cytoplasm.
Which of the following best designates a somatic cell containing 6 chromosomes?
2n = 6
If a plant has a diploid chromosome number of 60, how many chromosomes are present in its gametes?
30
The nucleolus is the structure in which ______ are formed.
ribosomes
Grana are stacks of ______ within chloroplasts.
thylakoids
Chlorophylls and carotenoid pigments are embedded in the:
thylakoid membranes.
Plastids that contain carotenoids but lack chlorophyll are known as:
chromoplasts.
______ are colorless plastids that are the precursors of other, more highly differentiated plastids.
Proplastids
Which of the following statements about mitochondria is FALSE?
They are generally larger than plastids.
A pivotal step in programmed cell death is the release of ______ from ______.
cytochrome c; mitochondria
Peroxisomes are organelles that:
self-replicate.
The ______ in the cell sap are responsible for the red and blue colors of many fruits and vegetables.
anthocyanins
Smooth endoplasmic reticulum is involved in ______ synthesis.
lipid
Which of the following lists the correct sequence in which glycoproteins travel through the Golgi complex?
Forming face, shuttle vesicles, maturing face, trans-Golgi network
Which of the following is NOT part of the endomembrane system?
mitochondrial membrane
Which of the following statements about microtubules is FALSE?
Their subunits are arranged in a solid cylinder.
The alignment of cellulose microfibrils in the cell wall is controlled by:
cortical microtubules.
Which of the following statements concerning actin filaments is FALSE?
They lack distinct plus and minus ends.
In plants, flagella are found only in:
motile sperm.
A ______ has an internal arrangement of nine triplets of microtubules.
basal body
Stretching of the cell wall can be prevented by the cross-linking of _____ with _____.
pectins; calcium
Which of the following statements concerning callose is FALSE?
It opens plasmodesmata between contiguous cells.
Which of the following lists the correct sequence of cell wall layers, beginning with the outermost layer and progressing inward?
middle lamella, primary wall, secondary wall
Which of the following statements about the primary wall is FALSE?
It is usually of uniform thickness.
An interruption in the secondary wall is called a:
pit.
Cellulose synthase is an enzyme situated in the:
plasma membrane.
In the cell cycle, interphase consists of:
the G1, G2, and S phases.
Which of the following statements concerning endoreduplication is FALSE?
It may result in gigantic nuclei.
Which of the following statements concerning checkpoints is FALSE?
Checkpoints differ significantly among eukaryotic cells.
DNA replication occurs during the ______ phase.
S
Which of the following is unique to cell division in plants?
migration of the nucleus to the center of the cell
In the developing cell plate, the initial polysaccharide is:
callose.
In late prophase, sister chromatids are joined by a constriction at the:
centromere.
The ______ is the earliest manifestation of the mitotic spindle.
prophase spindle
Sister chromatids become daughter chromosomes at the beginning of:
anaphase.
Chromosomes lengthen and become indistinct during:
telophase.
During ______, the nuclear envelopes and nucleoli re-form.
telophase
The longest phase of mitosis is always:
prophase.
Which of the following statements about the phragmoplast is FALSE?
It begins to form at the walls of the dividing cell and grows inward.
Water potential is defined as the:
potential energy of water.
The long-distance transport of sap in the phloem is an example of:
pressure-driven bulk flow.
What is the water potential, expressed in units of megapascals, of pure water?
0
In the absence of other factors affecting water potential, water will move FROM a region of ______ TO a region of ______.
low solute concentration; high solute concentration
Which of the following could be the water potential of a sucrose solution at atmospheric pressure and at sea level?
–10 MPa
Suppose a drop of dye is placed in one end of a tank of water. What happens next?
The dye molecules and the water molecules move down their respective concentration gradients.
Which of the following statements about diffusion is FALSE?
When the diffusing molecules become evenly distributed, their movement stops.
Which of the following substances is LEAST likely to diffuse across the plasma membrane?
an ion
Which of the following statements about solute movement in cells is FALSE?
Diffusion is an effective way to move substances between distantly separated cells.
Which of the following is the best definition of osmosis?
The net movement of water across a selectively permeable membrane.
Turgor pressure results most directly from:
water moving into a cell by osmosis.
Wall pressure:
is an inwardly directed pressure of the wall.
In plasmolysis:
the plasma membrane pulls away from the cell wall.
If a plant cell is placed in a solution with a relatively low water potential, the cell will:
undergo plasmolysis.
Wilting results most directly from _______ in plant cells.
the loss of turgor
When botanists speak of a “bilayer,” they are referring to a structure composed entirely of:
phospholipids.
The most abundant sterol in the plant cell membrane is:
stigmasterol.
The portion of a transmembrane protein embedded in the bilayer is:
hydrophobic.
By definition, all proteins attached to protruding portions of transmembrane proteins are:
peripheral proteins.
Which of the following statements concerning membrane structure is FALSE?
Transmembrane proteins lack hydrophilic sequences.
Although membranes were previously described by the “fluid-mosaic” model, recent evidence suggests that membranes:
are less fluid.
In the plasma membrane, carbohydrates are most likely to be found:
on the outer membrane surface.
What is the hypothesized role of carbohydrates in the plasma membrane?
recognizing molecules that interact with the cell
Most membrane carbohydrates are present in the form of:
glycoproteins.
The portion of a transmembrane protein that is embedded in the hydrophobic interior of the bilayer is usually in the form of a(n):
alpha helix.
Which of the following is NOT a function of membrane proteins?
making the membrane impermeable
Small nonpolar molecules, such as O2 and CO2, enter a cell by:
simple diffusion.
A steroid hormone would most likely enter a cell by:
simple diffusion.
A “gate” is most directly associated with a:
channel.
An aquaporin is a:
channel protein for water.
Aquaporins are found in the plasma membrane and the:
the mitochondrial membrane, the chloroplast membrane, the tonoplast, and the ER.
Which of the following statements about an electrochemical gradient is FALSE?
It is the driving force for the movement of charged and uncharged substances across a membrane.
If the concentration of K+ is higher outside a plant cell than inside, K+ will enter the cell by:
facilitated diffusion through channel proteins.
Symport is a transport system in which the transport of one solute:
depends on the transport of another solute in the same direction.
Which of the following processes in plant cell membranes requires ATP?
active transport
If the concentration of glucose is higher inside a cell than outside, glucose will enter the cell only by:
active transport.
In the active transport of sucrose, the secondary active transport system is the:
sucrose-proton symporter.
Proteins and polysaccharides will most likely enter a cell by:
vesicle-mediated transport.
A cell that ingests bacteria or cellular debris does so by:
phagocytosis.
In receptor-mediated endocytosis, specific receptors for the substances to be transported are localized in:
coated pits.
In receptor-mediated endocytosis, what happens immediately after the substance to be transported binds to a receptor?
The coated pit invaginates to form a coated vesicle.
Which of the following would NOT occur during signal recognition?
The signal molecule is transported out of the cell by exocytosis.
Two of the most common second messengers are:
calcium ions and cyclic AMP.
In the signal-transduction pathway involving Ca2+ ions in plants, which of the following occurs during the transduction step?
Calcium ions are released into the cytosol from the vacuole.
The symplast consists of:
all the protoplasts including their plasmodesmata.
Primary plasmodesmata are different from secondary plasmodesmata in that primary plasmodesmata:
are formed during cytokinesis.
Which of the following statements concerning the desmotubule is FALSE?
It is a main channel for transporting materials.
The cytoplasmic sleeve is the:
cytoplasmic channel involved in symplastic transport through a plasmodesma.
Which of the following statements concerning plasmodesmata is FALSE?
Their similar symplastic domains cause them to be passive structures.
Of the total solar energy that reaches the Earth, ______ percent is captured by the cells of photosynthetic organisms.
less than 1
The energy of a system is defined as:
its capacity to do work.
According to the first law of thermodynamics, the total energy of ______ is ______.
the universe; constant
The first law of thermodynamics states that:
energy can be changed from one form to another, but it cannot be created or destroyed.
Which of the following is NOT an example of potential energy?
Water at the bottom of a waterfall
The first law of thermodynamics states that the total energy of a system and its surroundings after an energy conversion is ______ the total energy before the conversion.
equal to
One way of stating the second law of thermodynamics is:
the entropy of the universe is increasing.
The second law of thermodynamics states that if no energy enters or leaves the system under study, the potential energy of the final state will be______ the potential energy of the initial state.
less than
An exergonic reaction:
is a reaction in which the potential energy of the final state is less than that of the initial state.
ΔH refers to the:
change in enthalpy.
Entropy refers to the ______ of a system.
disorder or randomness
ΔG refers to the change in ______ of the system.
free energy
Which of the following equations relating enthalpy, entropy, and free energy is correct?
ΔG = ΔH - T ΔS
ΔG is negative.
are exergonic.
Which of the following statements about living cells is FALSE?
They are at equilibrium with their surroundings.
Oxidation is defined as the:
loss of electrons.
In biological reactions, when a molecule is oxidized it ______ an electron and a(n) ______.
loses; proton
In the following reaction, which molecule is oxidized?
glucose + oxygen → carbon dioxide + water
Oxygen
During the oxidation of glucose in the cell, most of the energy is released:
in small amounts.
An enzyme:
functions as a catalyst.
Most enzymes are:
proteins.
A substrate binds to its enzyme at a location called the ______ site.
active
A negatively charged portion of a substrate molecule would most likely fit into a ______ region of its enzyme’s active site.
positively charged
The general name for a nonprotein component required by some enzymes is a:
cofactor
Most enzymes that catalyze phosphorylation reactions require ______ as a cofactor.
Mg2+
The vitamin niacin is part of the ______ molecule.
NAD+
In a NAD+ molecule, a pyrophosphate bridge joins:
two ribose molecules.
Which of the following statements about metabolic pathways is FALSE?
The enzymes of most pathways allow intermediate products to accumulate.
Isozymes are:
different enzymes that catalyze identical reactions.
In an allosteric enzyme, the substrate binds at the ______ site and the regulatory substance binds at the ______ site.
active; effector
In feedback inhibition, the ______ enzyme in a metabolic pathway is inhibited by the ___________.
first; end product
Which of the following is NOT a component of an ATP molecule?
a pyrophosphate bridge
In an ATP molecule, phosphoanhydride bonds link:
the phosphate groups together.
Which type of enzyme catalyzes the following reaction?
ATP + H2O → ADP + phosphate
ATPase
Which statement about the reaction ATP + H2O → ADP + phosphate is FALSE?
The reactants are more stable than the products.
Which of the following is a phosphorylation reaction catalyzed by a kinase in plant cells?
ATP + glucose → glucose phosphate + ADP
Which of the following statements about sucrose synthesis is FALSE?
In the cell, sucrose synthesis is endergonic.
Which of the following statements about the reactions of glucose oxidation is FALSE?
Oxygen is oxidized.
Which of the following statements concerning fermentation is FALSE?
It involves O2 as the ultimate electron acceptor.
Which of the following does NOT occur during respiration?
hydrolysis of starch to glucose
Formation of ATP from ADP and phosphate as a result of electron transport occurs in:
oxidative phosphorylation.
In respiration, most of the energy in the original glucose molecule is:
released as heat.
In glycolysis, one molecule of glucose is converted to ______ molecules of ______.
three; pyruvate
Which of the following statements concerning glycolysis is FALSE?
It is an aerobic process.
Where in the cell does glycolysis occur?
the cytosol
When one speaks of the cell’s “net energy harvest” from glycolysis one is referring to the amount of:
ATP and NADH
The preparatory phase of glycolysis involves:
2 molecules of ATP only.
As part of the first step in the first preparatory reaction of glycolysis:
glucose is phosphorylated.
For every molecule of glucose that begins glycolysis, how many ATP molecules are consumed?
2
As part of the cleavage step in glycolysis, glucose is:
converted to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate.
For each molecule of glucose that completes glycolysis, how many NAD+ molecules are reduced?
2
For every glucose molecule that completes glycolysis, how many total molecules of ATP are produced?
4
In glycolysis, what is the net energy harvest of ATP molecules per molecule of glucose?
2
Most of the enzymes of the citric acid cycle are found in the _____ of the _____.
matrix; mitochondria
Pyruvate is converted to acetyl CoA in the ____ of the _____.
matrix; mitochondria
For every molecule of glucose that begins glycolysis, how many molecules of acetyl CoA are produced?
2
During the conversion of pyruvate to acetyl CoA, _____ is produced.
CO2
Upon entering the citric acid cycle, the acetyl group combines with ______ to produce ______.
oxaloacetate; citrate
After acetyl CoA enters the citric acid cycle, the coenzyme A portion of the molecule:
is released.
Which of the following does NOT occur during the citric acid cycle?
oxidative phosphorylation
In each turn of the citric acid cycle, how many molecules of ATP are produced?
1
In the citric acid cycle, how many molecules of FADH are produced per molecule of glucose?
2
In the citric acid cycle, how many molecules of NADH are produced per molecule of glucose?
6
Most of the carriers of the electron transport chain are:
embedded in the inner mitochondrial membrane.
Which of the following statements about iron-sulfur proteins is FALSE?
They carry electrons and protons.
The most abundant component(s) of the mitochondrial electron transport chain is/are:
coenzyme Q.
Who am I? I move freely within the mitochondrial membrane and thus shuttle electrons between other carriers.
CoQ
The energy released by the flow of electrons along the electron transport chain is used directly to:
pump protons.
The final electron acceptor in the electron transport chain is:
oxygen.
For each pair of electrons passing from NADH to oxygen, how many ATP molecules can be generated?
3
Oxidative phosphorylation depends on a gradient of ______ across the mitochondrial membrane.
protons
In the electron transport chain, electrons pass from complex ____ directly to O2.
IV
The electrochemical gradient resulting from electron transport is due to differences in ______ across the inner mitochondrial membrane.
electric charge and proton concentration
Which of the following statements about ATP synthase is FALSE?
It transports electrons.
The number of ATP molecules generated from each NADH produced in glycolysis is _______.
2
The number of ATP molecules generated from each NADH produced in the conversion of pyruvate to acetyl CoA is _______.
2
Most of the ATP formed in respiration is produced by reactions associated with:
the electron transport chain.
The process of beta oxidation is involved in the breakdown of:
triglycerides.
Under anaerobic conditions, yeasts and most plant cells convert pyruvate to:
ethanol and carbon dioxide.
Which of the following processes occurs in both lactate fermentation and alcohol fermentation?
oxidation of NADH
In lactate fermentation and alcohol fermentation, the net ATP production is ______ molecules of ATP per molecule of glucose.
2
“Catabolism” specifically refers to the various pathways in which organisms ______ organic molecules.
break down
The metabolic “hub” of the cell is:
the citric acid cycle.
Who provided the first experimental evidence that soil alone does not nourish the plant?
Jan Baptista van Helmont
The O2 evolved in photosynthesis comes from:
water.
F. F. Blackman showed that:
photosynthesis has a light-dependent stage and a light-independent stage.
Which of the following statements about the electromagnetic spectrum is FALSE?
The longer the wavelength of light, the more energy it has.
Light is composed of particles called:
photons.
Chlorophyll absorbs light principally in the ______ wavelengths.
blue and violet
An action spectrum is different from an absorption spectrum in that an action spectrum:
is the relative effectiveness of different wavelengths for a specific process.
Which of the following is the very next event that occurs when a chlorophyll molecule absorbs light?
The electron is boosted to an excited state.
Which pigment occurs in all photosynthetic eukaryotes?
Chlorophyll a
The primary function of ______ is as an anti-oxidant.
carotenoids
Xanthophylls and carotenes:
are carotenoids.
The energy-transduction reactions of photosynthesis are also called the ______ reactions.
light
Which of the following statements about an antenna complex is FALSE?
It converts light energy into chemical energy.
The light-harvesting complex is different from a photosystem in that the light-harvesting complex:
lacks a reaction center.
In the antenna complex, light energy is transferred from one pigment molecule to another by:
resonance energy transfer.
In contrast to Photosystem I, Photosystem II is located primarily:
in grana thylakoids.
In Photosystem II, energized electrons are transferred from pheophytin directly to:
PQA.
In the light reactions, the cytochrome b6/f complex receives electrons directly from:
plastoquinol.
Following photolysis, the resulting protons are released into the ______, contributing to the proton gradient across the ______ membrane.
lumen of the thylakoid; thylakoid
The ______ complex links photosystems I and II.
cytochrome b6/f
In photophosphorylation, the role of the ATP synthase complex is to provide a channel for protons to flow back into the:
chloroplast stroma.
Which of the following events is NOT associated with Photosystem I?
transfer of electrons from cytochromes to iron-sulfur proteins
Which of the following statements concerning ferredoxin is FALSE?
It is found in the chloroplast grana.
Which of the following is produced during noncyclic AND cyclic electron flow?
ATP
During cyclic electron flow, electrons are transferred directly from P700 to Ao to:
the photosynthetic electron transport chain.
The Calvin cycle takes place in the:
chloroplast stroma.
Carbon dioxide is “fixed” by bonding to:
ribulose 1,5-bisphosphate.
The role of Rubisco is to catalyze the conversion of:
CO2 to an unstable six-carbon compound.
How many molecules of CO2 are fixed during each turn of the Calvin cycle?
one
Which of the following does NOT occur in the Calvin cycle?
ADP is phosphorylated to ATP.
Which of the following statements about the Calvin cycle is FALSE?
It uses ATP from noncyclic, but not cyclic, photophosphorylation.
Most of the glyceraldehyde 3-phosphate not exported to the cytosol is converted to ______ and stored in the chloroplasts.
starch
Rubisco can use ______ or CO2 as a substrate.
O2
Which of the following statements about photorespiration is FALSE?
It yields ATP but not NADPH.
Which of the following conditions favors photorespiration?
a hot, dry environment
One of the benefits of photorespiration is removing toxic:
phosphoglycolate.
In the C4 pathway, the enzyme PEP carboxylase:
catalyzes the formation of oxaloacetate.
The malate or aspartate produced in the C4 pathway moves next into:
the bundle-sheath cells.
Kranz anatomy is characterized by a layer of ____ around a layer of ____.
mesophyll cells; bundle-sheath cells
Suaeda aralocaspica is different from many other C4 plants because it:
lacks Kranz anatomy.
Compared with a C3 plant, a C4 plant:
needs more ATP to fix CO2.
Which of the following is a C4 plant?
crabgrass
Compared with C3 plants, C4 plants:
use nitrogen more efficiently.
In CAM plants, malate formed as the end product of CO2 fixation in the dark is stored as malic acid in the:
vacuole.
Which of the following is most likely to occur in a leaf cell of a CAM plant during the day?
decarboxylation of malic acid
Which of the following is not considered a CAM plant?
wheat
Which of the following statements about CAM plants is FALSE?
All CAM plants are flowering plants.
By crossing different varieties of peas ______ discovered the principles of heredity.
Gregor Mendel
Which of the following statements about sexual reproduction is FALSE?
It is the principal mode of reproduction in prokaryotes.
Which of the following statements about homologous chromosomes is FALSE?
Homologs resemble each other in size but not in shape.
Chromatin consists of:
DNA, histones, and other proteins.
Which of the following statements concerning histones is FALSE?
They are present in four distinct types.
A nucleosome consists of:
a core of histones wrapped with DNA.
