The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
loses electrons and loses potential energy.
Which of the following statements describes the results of this
reaction?
C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O + Energy
C₆H₁₂O₆ is oxidized and O₂ is reduced
When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction reaction, the molecule becomes
oxidized.
The ATP made during glycolysis is generated by
substrate-level phosphorylation.
In cellular respiration, the energy for most ATP synthesis is supplied by
a proton gradient across a membrane ****
In chemiosmotic phosphorylation, what is the most direct source of energy that is used to convert ADP + Pi to ATP?
energy released from movement of protons through ATP synthase, down the electrochemical gradient
Which metabolic pathway is common to both cellular respiration and fermentation?
glycolysis
In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of
ATP, CO₂, and ethanol (ethyl alcohol).
Which statement best supports the hypothesis that glycolysis is an ancient metabolic pathway that originated before the last universal common ancestor of life on Earth?
Glycolysis is widespread and is found in the domains Bacteria, Archaea, and Eukarya. ******************************************
Why is glycolysis considered to be one of the first metabolic pathways to have evolved?
It does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms. *****************************************************
A mutation in yeast makes it unable to convert pyruvate to ethanol. How will this mutation affect these yeast cells?
The mutant yeast will be unable to grow anaerobically.
Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?
glycolysis
Most CO₂ from catabolism is released during
the citric acid cycle. **********************************************
Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?
ATP and NADPH
When oxygen is released as a result of photosynthesis, it is a direct
by-product of
A) reducing NADP⁺.
splitting water molecules.
Some photosynthetic organisms contain chloroplasts that lack photosystem II, yet are able to survive. The best way to detect the lack of photosystem II in these organisms would be
to test for liberation of O₂ in the light.
What does the chemiosmotic process in chloroplasts involve?
establishment of a proton gradient across the thylakoid membrane ***************************************************
In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from
the stroma to the thylakoid space ***
Which of the following statements best describes the relationship between photosynthesis and respiration?
Photosynthesis stores energy in complex organic molecules, whereas respiration releases it. **********************************************
In metabolic processes of cell respiration and photosynthesis, prosthetic groups such as heme and iron-sulfur complexes are encountered in components of the electron transport chain. What do they do?
both oxidize and reduce during electron transport
the centromere is a region in which
chromatids remain attached to one another until anaphase
why do chromosomes coil during mitosis
to allow the chromosomes to move without becoming entangled and breaking
which of the following best describes how chromosomes move toward the poles of the spindle during mitosis
the chromosomes are "reeled in" by the contraction of spindle microtubules and motor proteins
during which phase of mitosis do the chromatids become chromosomes
telophase
which of the following does not occur during mitosis
replication of the DNA
which of the following is true of a species that has a chromosome number of 2n = 16
each cell has eight homologous pairs
if a cell has completed the first meiotic division and is just beginning meiosis 2 which of the following is an appropriate description of its contents
it has half the amount of DNA as the cell that began meiosis.
chromatids are separated from each other
the statement is true for mitosis and meiosis II
******************************************
independent assortment of chromosomes occurs
the statement is true for meiosis 1 only
centromeres of sister chromatids disjoin and chromatids separate.
telophase II
independent assortment of chromosomes is a result of
the random and independent way in which each pair of homologous chromosomes lines up at the metaphase plate during meiosis I
which of the following statements is true of linkage?
the closer two genes are on a chromosome, the lower the probability that a crossover will occur between them.
if nondisjunction occurs in meiosis II during gametogenesis, what will be the result at the completion of meiosis
1/4 of the gametes will be n + 1, 1/4 will be n - 1, and 1/2 will be n. ******************************
suppose that a gene on human chromosome 18 can be imprinted in a given pattern in a female parent but not in a male parent. a couple in whom each maternal meiosis is followed by imprinting of the gene have children. what can we expect as a likely outcome?
all the children will bear their mother's imprinting pattern but only daughters will then pass it down
which of the following statements is true about protein synthesis in prokaryotes?
translation can begin while transcription is still in progress.