Practice Questions Ch. 10,12,13
Cells will usually divide if they receive the proper signal at a checkpoint in which phase of the cell cycle?
G1
Calvin cycle outputs
G3P, ADP, NADP+
In the light reactions, light energy is used to oxidize _____ to _____
H2O ... O2
What is the correct order of electron flow in the light reactions of photosynthesis?
H2O → P680 chlorophyll a pair → PS II primary electron acceptor → Pq → cytochrome complex → Pc → P700 chlorophyll a pair → PS I primary electron acceptor → Fd → NADPH
During _____ the cell grows and replicates both its organelles and its chromosomes.
Interphase
Nucleoli are present during _____.
Interphase
True or false? The light-dependent reactions of photosynthesis use water and produce oxygen.
True
E, the stroma
Where does the Calvin cycle occur?
C and D
Which of these cells is (are) haploid?
E
Which of these phases encompasses all of the stages of mitosis but no other events?
E, ATP synthase
Which of these phosphorylates ADP to make ATP?
B
_____ releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment.
A, Photosystem II
_____ splits water into 1/2 O2, H+, and e- .
Which of the following statements best describes a cleavage furrow?
a groove in the plasma membrane between daughter nuclei
Which of these is NOT a carcinogen? -UV light -fat -testosterone -cigarette smoke -all of the above are carcinogens
all of the above are carcinogens
Homologous chromosomes migrate to opposite poles during _____.
anaphase I
During _____ sister chromatids separate. (meiosis)
anaphase II
True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.
False
At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids.
telophase I
At the end of _____ and cytokinesis there are four haploid cells.
telophase II
Which of the following phrases defines the term genome? -the complete set of an organism's genes and other DNA sequences -the complete set of an organism's polypeptides -the complete set of a species' polypeptides -The complete set of a species expressed traits
the complete set of an organism's genes and other DNA sequences
During _____ both the contents of the nucleus and the cytoplasm are divided.
the mitotic phase
Why do some species employ both mitosis and meiosis, whereas other species use only mitosis?
they need both if they are reproducing sexually
Which of the following is true of benign tumors, but not malignant tumors? -they can divide indefinitely if an adequate supply of nutrients is available -they have an unusual number of chromosomes -they migrate from the initial site of transformation to other organs or tissues -they remain confined to their original site -they are the result of the transformation of normal cells
they remain confined to their original site
C4 plants differ from C3 and CAM plants in that C4plants _____.
transfer fixed carbon dioxide to cells in which the Calvin cycle occurs
Meiosis I produces _____ cells, each of which is _____.
two ... haploid
The light reactions of photosynthesis use _____ and produce _____.
water ... NADPH
Will the sister chromatids separate from each other?
yes
Will this animal cell elongate during mitosis?
yes
Which of the following statements are true of cytokinesis in plant cells? Select the two that apply. -The cell plate consists of the plasma membrane and cell wall that will eventually separate the two daughter cells. -The plasma membrane of the parent cell grows inward, eventually joining with the cell plate. -Vesicles from the Golgi apparatus move along microtubules, coalesce at the plane of cell division, and form a cell plate. -After chromosome separation is complete, a network of microfilaments forms near the plane of cell division that will separate the two new cells.
-The cell plate consists of the plasma membrane and cell wall that will eventually separate the two daughter cells. -Vesicles from the Golgi apparatus move along microtubules, coalesce at the plane of cell division, and form a cell plate.
How many electrons at a time are passed between the pigment molecules in the light-harvesting complexes?
0
A diploid organism whose somatic (nonsex) cells each contain 32 chromosomes produces gametes containing _____ chromosomes.
16
For every molecule of O2 that is released by photosystem II, ____ H2O molecules are needed, which together pass ____ electrons to the PS II reaction-center complex.
2 ... 4
In human gamete production there is an average of _____ crossover events per chromosome pair.
2-3
Normal human gametes carry _____ chromosomes.
23
Which of these equations best summarizes photosynthesis? -6 CO2 + 6 H2O → C6H12O6 + 6 O26 -CO2 + 6 O2 → C6H12O6 + 6 H2O -C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy -C6H12O6 + 6 O2 → 6 CO2 + 12 H2O -H2O → 2 H+ + 1/2 O2 + 2e-
6 CO2 + 6 H2O → C6H12O6 + 6 O26
Which of the following statements describes an example of alternation of generations? -A diploid animal produces gametes by meiosis, and the gametes undergo fertilization to produce a diploid zygote. -A diploid plant (sporophyte) produces a spore by meiosis that gives rise to a multicellular, haploid pollen grain (gametophyte). -A haploid plant produces gametes by meiosis and the gametes fuse to produce a new plant. -A grandparent and grandchild each have dark hair, but the parent has blond hair.
A diploid plant (sporophyte) produces a spore by meiosis that gives rise to a multicellular, haploid pollen grain (gametophyte).
Chloroplast membrane vesicles are equilibrated in a simple solution of pH 5 . The solution is then adjusted to pH 8 . Which of the following conclusions can be drawn from these experimental conditions?
ATP will not be produced because there is no ADP and inorganic phosphate in the solution
outputs of light reactions
ATP, NADPH, O2
Centromeres divide and sister chromatids become full-fledged chromosomes during _____.
Anaphase
Which of the following statements best describes density-dependent inhibition? -As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells, and they signal each other to stop dividing. -As cells become more numerous, the level of waste products increases, which slows metabolism and inhibits growth. -As cells become more numerous, the protein kinases they produce begin to compete with each other, such that the proteins produced by one cell essentially cancel those produced by its neighbor. -As cells become more numerous, they begin to squeeze against each other, restricting their size.
As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells, and they signal each other to stop dividing.
Which of the following statements best describes the relationship between autotrophs and heterotrophs? -Autotrophs produce their organic molecules from CO2 and other inorganic molecules, whereas heterotrophs obtain their organic molecules from compounds produced by other organisms. -Heterotrophs produce their organic molecules from CO2 and other inorganic molecules, whereas autotrophs obtain their organic molecules from compounds produced by other organisms. -Both autotrophs and heterotrophs produce some of their organic molecules from CO2 and other inorganic molecules. -Heterotrophs are considered the producers of the biosphere, whereas autotrophs are consumers. Submit
Autotrophs produce their organic molecules from CO2 and other inorganic molecules, whereas heterotrophs obtain their organic molecules from compounds produced by other organisms.
The electrons derived from this oxidation reaction in the calvin cycle are used to reduce ____ to ____
CO2 ... G3P
What is the importance of the light-independent reactions in terms of carbon flow in the biosphere?
CO2 is unusable until plants have "fixed" this carbon into sugar.
Calvin cycle inputs
CO2, ATP, NADPH
In the cells of some organisms, mitosis occurs without cytokinesis. This will result in
Cells with more than one nucleus
A and C, The photosystems contain chlorophyll.
Chlorophyll can be found in _____.
During interphase, most of the nucleus is filled with a complex of DNA and protein in a dispersed form called ____
Chromatin
In most eukaryotes, division of the nucleus is followed by____ , when the rest of the cell divides.
Cytokinesis
In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells.
Cytoplasm
Why is it correct to say that the linear electron flow of the light reactions directlycaptures energy in NADPH but only indirectly captures energy in ATP?
Electrons are directly transferred to NADP+ to form NADPH, but electron flow is used to generate a proton gradient for ATP synthesis. Electrons are not directly transferred to ATP.
C
Energized electrons from ____ are used to reduce NADP+.
True or false? The chemiosmotic hypothesis states that the synthesis of ATP generates a proton gradient that leads to electron flow through an electron transport chain.
False
During mitosis, microtubules attach to chromosomes at the ____
Kinetochore
Mitosis can occur in both haploid and diploid cells, but meiosis can only occur in diploid cells. Why?
Meiosis produces daughter cells with half the number of chromosome sets of the parent cell; therefore, the parent cell must be diploid.
Homologous pairs of chromosomes are lined up independently of other such pairs during _____.
Metaphase I
____ is a cell structure consisting of microtubules, which forms during early mitosis and plays a role in cell division.
Mitotic Spindle
The Electrons derived from this oxidation reaction in the light reactions are used to reduce ____ to ____
NADP+ ... NADPH
Which of the following molecules is the primary product of photosystem I?
NADPH
The Calvin cycle oxidizes the light reactions product ____ to ____
NADPH ... NADP+
If the Calvin cycle slows down, what will happen to the rate of O2 production in PS II, and why?
O2 production will slow down because less NADP+ will be regenerated in the Calvin cycle.
Which term describes ATP production resulting from the capture of light energy by chlorophyll?
Photophosphorylation
In C3 plants the conservation of water promotes _____.
Photorespiration
Which of the following statements best describes the relationship between photosynthesis and cellular respiration? -Photosynthesis occurs only in plants; cellular respiration occurs only in animals. -Photosynthesis stores energy in complex organic molecules; cellular respiration releases energy from complex organic molecules. -Photosynthesis is catabolic; cellular respiration is anabolic. -Cellular respiration runs the biochemical pathways of photosynthesis in reverse.
Photosynthesis stores energy in complex organic molecules; cellular respiration releases energy from complex organic molecules.
Which of the following statements best describes how cytokinesis differs between plant and animal cells? -Cytokinesis occurs between metaphase and anaphase in plant cells; it occurs after anaphase in animal cells. -Plant cells deposit vesicles containing cell wall building blocks on the metaphase plate; animal cells form a cleavage furrow. -The contractile filaments found in plant cells are structures composed of carbohydrates; the cleavage furrow in animal cells is composed of contractile proteins. -The structural proteins of plant cells separate the two cells; in animal cells, a cell membrane separates the two daughter cells.
Plant cells deposit vesicles containing cell wall building blocks on the metaphase plate; animal cells form a cleavage furrow.
Spindle fibers attach to kinetochores during _____.
Prometaphase
Chromosomes become visible during _____.
Prophase
According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?
Proton Gradient
Which of the following particles can pass through the ATP synthase channel?
Protons
_____ has a longer wavelength than _____.
Red ... green
Which molecule is regenerated in the regeneration phase of the Calvin cycle? Without regeneration of this molecule, the Calvin cycle would stop.
RuBP
After DNA replication, each duplicated chromosome consists of two of which of the following structures?
Sister chromatids
Which of the following molecules best describes the primary form in which plants stockpile extra sugar produced by photosynthesis?
Starch
Most sugar is transported from the leaves to the rest of the plant in the form of which of the following molecules?
Sucrose
Cytokinesis often, but not always, accompanies _____.
Telophase
When a pigment molecule in a light-harvesting complex absorbs a photon of light, what happens to its excited-state electron?
The electron falls back to its ground state, while passing its excited-state energy to an electron in a nearby pigment molecule.
Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis? -The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions. -The light-independent reactions release energy, and the light-dependent reactions require energy. -The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions. -The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions.
The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.
What is the biological significance of the light-independent reactions of photosynthesis?
They convert carbon dioxide to sugar
After chromosomes condense, the ____ is the region where the identical DNA molecules are most tightly attached to each other.
centromeres
____ are the organizing centers for microtubules involved in separating chromosomes during mitosis.
centrosomes
One difference between cancer cells and normal cells is that cancer cells
continue to divide even when they are tightly packed together.
____ is a carcinogen that promotes colon cancer.
fat
DNA replication produces two identical DNA molecules, called ____, which separate during mitosis.
sister chromatids
Many diploid organisms produce haploid gametes for reproduction. Which of the following best describes how the diploid number of chromosomes is restored in the offspring of these organisms? -synapsis during prophase of meiosis I creates random combinations of alleles -DNA replication creates homologous chromosomes -independent assortment in meiosis allows random combinations of chromosomes -fertilization combines chromosomes from each parent into resulting zygote
fertilization combines chromosomes from each parent into resulting zygote
Meiosis II typically produces _____ cells, each of which is _____.
four ... haploid
In dividing cells, most of the cell's growth occurs during ____
interphase
Which set of reactions uses H2O and produces O2?
light dependent reactions
inputs of light reactions
light, water, ADP, NADP+
Human gametes are produced by _____.
meiosis
During _____ chromosomes align single file along the equator of a haploid cell.
metaphase II
Asexual reproduction occurs during which of the following processes? -meiosis -fertilization -the exchange of chromosomes between organisms of different species -mitosis
mitosis
Will the chromosomes move to the poles of the cell?
no
Crossing over, resulting in an increase in genetic variation, occurs between _____.
non sister chromatids of homologous chromosomes
Which process produces oxygen?
photosynthesis
Synapsis occurs during _____.
prophase I
During _____ a spindle forms in a haploid cell.
prophase II