Unit 4
In a nucleosome, what is the DNA wrapped around?
a) polymerase molecules
b) ribosomes
c) mRNA
d) histones
e) chromatin
d) histones
According to the fluid mosaic model of membrane structure, the mosaic part of the membrane is mostly _____.
a) carbohydrates
b) nucleic acids
c) phospholipids
d) cholesterol
e) protein
e) proteins
The movement of a substance across a biological membrane against its
concentration gradient and requiring energy is which of the following?
A. Diffusion
B. Active transport
C. Osmosis
D. Facilitated diffusion
E. Exocytosis
B. Active transport
All of the following occur as a result of the Krebs cycle except:
a) ATP is formed
b) NADH is formed
c) FADH2 is formed
d) CO2 is released
e) electrons and protons add to O2 to form water
e) electrons and protons add to O2 to form water
The frequency of crossing over between any two linked genes is __
a) higher if they are recessive
b) difficult to predict
c) determined by their relative dominance
d) the same as if they were not linked
e) proportional to the distance between them
e) proportional to the distance between them
In a population that is in Hardy-Weinberg equilibrium, the frequency of the allele a is 0.3. What is the percentage of the population that is homozygous for this allele?
a) 3
b) 9
c) 21
d) 30
e) 90
b) 9
Which of the following is not a component of a nucleus?
a) nucleolus
b) nuclear lamella
c) cristae
d) nuclear pores
e) nuclear envelope
c) cristae
The frequency of crossing over between any two linked genes is ___________.
A. higher if they are recessive
B. difficult to predict
C. determined by their relative dominance
D. the same as if they were not linked
E. proportional to the distance between them
E. proportional to the distance between them
Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?
a) the splitting of water
b) the absorption of light energy by chlorophyll
c) the flow of electrons from photosystem II to photosystem I
d) the synthesis of ATP
e) the reduction of NADP+
d) the synthesis of ATP
A Barr body is normally found in the nucleus of ___
a) unfertilized egg cells only
b) sperm cells only
c) somatic cells of a female only
d) somatic cells of a male only
e) both male and female somatic cells
c) somatic cells of a female only
Which of the following is the unit of evolution?
a) gene
b) chromosome
c) individual
d) population
e) species
d) population
Transport processes across cellular membranes that require energy are ____
a) active transport
b) diffusion and facilitated diffusion
c) facilitated diffusion
d) facilitated diffusion and active transport
e) diffusion
a) active transport
____ is similarity due to shared ancestry.
_____ is similarity due to convergent evolution.
Homology
Analogy
All of the following occur as a result of the Krebs cycle except:
A. ATP is formed.
B. NADH is formed.
C. FADH2 is formed.
D. CO2 is released.
E. Electrons and protons add to O2 to form water.
E. Electrons and protons add to O2 to form water.
All of the following are found in prokaryotic messenger RNA except ____
a) the AUG codon
b) the UGA codon
c) introns
d) uracil
e) both C and D
c) introns
The similarity of the homeobox in many different kinds of organisms is evidence ___
a) of convergent evolution
b) of the common ancestry of different life forms
c) of its recent origin
d) that it is not responsive to natural selection
e) of analogy
b) of the common ancestry of different life forms
Which type of transport process requires transporter proteins embedded in the membrane?
a) facilitated diffusion
b) active transport
c) diffusion and facilitated diffusion
d) facilitated diffusion and active transport
e) diffusion
d) facilitated diffusion and active transport
A ______ consists of an ancestral species and some, but not all, of the descendants.
a) monophyletic
b) paraphyletic grouping
c) polyphyletic grouping
b) paraphyletic grouping
Gamete cells are _____________.
A. diploid
B. haploid
C. formed by meiosis
D. A and C
E. B and C
E. B and C
Which of the following was not a component of Mendel's hypothesis to explain genetic inheritance?
a) Different alleles account for variations observed in inherited characters
b) An organism inherits two alleles, one from each parent
c) A dominant allele is fully expressed when two alleles differ
d) The two alleles for each character segregate during gamete production
e) recessive alleles always skip a generation
e) recessive alleles always skip a generation
Natural selection is based on all of the following except ____.
a) variation exists within populations
b) the fittest individuals leave the most offspring
c) there is differential reproductive success within populations
d) populations tend to produce more individuals than the environment can support
e) use or disuse of organs during one generation causes modifications of these same organs in subsequent generations
e) use or disuse of organs during one generation causes modifications of these same organs in subsequent generations
Which of the following polymers is not a polysaccharide?
a) cellulose
b) amylopectin
c) starch
d) glycogen
e) All of the above are polysaccharides
e) All of the above are polysaccharides
If nondisjunction occurs in meiosis II during gametogenesis, what will be the result at the completion of meiosis?
A. All the gametes will be diploid.
B. Two gametes will be n + 1 and two will be n - 1.
C. There will be three extra gametes.
D. Two of the four gametes will be haploid and two will be diploid.
E. One gamete will be n + 1, one will be n - 1, and two will be n.
E. One gamete will be n + 1, one will be n - 1, and two will be n.
If a cell contains 24 chromatids at the start of meiosis, how many chromosomes
are present in the daughter cells?
A. 6
B. 12
C. 24
D. 48
E. 96
A. 6
The distribution of alleles into gametes is described by ___.
a) Mendel's Law of Segregation only
b) Mendel's Law of Independent Assortment only
c) Both Mendel's Law of Segregation and Law of Independent Assortment
d) linked genes
e) recombination
c) Both Mendel's Law of Segregation and Law of Independent Assortment