BIO 182 cog books M3 + M4 UPDATED
ACTUAL Exam Questions and CORRECT
Answers
True or False? If the slope of the relationship between the phenotype and fitness is positive,
natural selection would decrease the phenotype over generations. - CORRECT
ANSWER - False. If the relationship is positive that phenotype would increase.
True or False? If the parameter for the squared term is negative, natural selection will likely
stabilize the phenotype at an intermediate value.
(y=ax^2+bx+c) - CORRECT ANSWER - True. (Likely being the key word. If x is
negative it will become positive when squared. But bx will continue to grow more negative.
Eventually bx will be more negative than ax^2.
What is Fitness? - CORRECT ANSWER - The relative number of viable, fertile, offspring
an organism produces.
What type of selection is most common? - CORRECT ANSWER -
True or False? Directional selection is more likely to be weak than strong. - CORRECT
ANSWER - True
True or False? Stabilizing selection occurs more often than disruptive selection. - CORRECT
ANSWER - False. They are very similar in frequency.
A researcher studied the relationship between the phenotypes of snakes and their fitness. First, he
measured the color patterns and the escape behavior of hundreds of snakes. For color pattern,
snakes were scored as being either checkered or striped (see photos below). For escape behavior,
snakes were chased by simulating a predator attack; some snakes moved in a straight line while
fleeing, but others tended to turn frequently. After recording these phenotypes, the researcher
released the snakes in their natural environment. A year later, he returned to see which snakes
had survived. The survival of snakes was used as a proxy of fitness. The figure below shows the
,relationships between color pattern and relative fitness for snakes that flee straight and snakes
that flee by turning. - CORRECT ANSWER - Info for next 5 questions.
A snake with stripes would be more likely to survive by fleeing predators in a straight line. -
CORRECT ANSWER - True
Regardless of escape behavior, the color pattern of snakes will be influenced by directional
selection. - CORRECT ANSWER - True
Over many generations, the population of snakes should evolve toward striped snakes that flee
by turning or checkered snakes that flee straight. - CORRECT ANSWER - False
The strength of selection for a color pattern is greater in snakes that flee by turning than in
snakes that flee straight. - CORRECT ANSWER - True
Although the researcher estimated fitness by survival, he could have also used another proxy for
fitness, such as mating success. - CORRECT ANSWER - True
Mitosis - CORRECT ANSWER - a type of cell division that results in two daughter cells
each having the same number and kind of chromosomes as the parent nucleus, typical of
ordinary tissue growth.
Meiosis I - CORRECT ANSWER - a cycle through which a diploid cell divides to create
two haploid cells, each receiving one of the homologous chromosomes.
Meiosis II - CORRECT ANSWER - a cycle through which the two haploid cells divide to
form four haploid cells, which later develop into sperm or eggs.
haploid cell - CORRECT ANSWER - a cell that contains a single set of chromosomes.
The term haploid can also refer to the number of chromosomes in egg or sperm cells, which are
also called gametes. In humans, gametes are haploid cells that contain 23 chromosomes, each of
which a one of a chromosome pair that exists in diplod cells.
, diploid cell - CORRECT ANSWER - A cell containing two copies of each chromosome is
referred to as a 'diploid cell'; human somatic cells are diploid: they contain 46 chromosomes, 22
pairs of autosomes and a pair of sex chromosomes.
True or False? Natural selection will likely eliminate deleterious alleles more quickly with sexual
reproduction than with asexual reproduction. - CORRECT ANSWER - True. Sexual
reproduction is faster. This causes both deleterious alleles and alleles that are beneficial to be
removed or passed on faster.
True or False? In a rapidly changing environment, a population would likely benefit more from
sexual reproduction than from asexual reproduction. - CORRECT ANSWER - True.
Rapidly changing environments require organisms to adapt faster.
True or False? If a parent passes one copy of each chromosome to offspring, alleles on the same
chromosome would be inherited together. - CORRECT ANSWER - True. The alleles are
on the same chromosome. If that chromosome is passed on then both alleles would be inherited.
True or False? If Mendel had compared traits controlled by genes on the same chromosome, his
results would not have matched the predictions of his model. - CORRECT ANSWER -
True
Use this information and your knowledge of biology to answer the following questions.
In the fruit fly, Drosophila melanogaster, a phenotype known as barred eyes sometimes appears,
in which the eyes are shaped like thin bars instead of being round. Additional crosses revealed
that a dominant allele on the X chromosome causes barred eyes. Oddly, however, the allele
arises only when two flies with normal eyes are crossed. In this case, fewer than 1% of the
offspring will have barred eyes. Male offspring never develop barred eyes. Researchers
hypothesized that the allele forms when the X chromosomes of a female cross over unequally
during meiosis, leading to one long and one short chromosome. This allele lies at a locus directly
next to a locus called B but on the opposite end of the chromosome from locus A. - CORRECT
ANSWER - Next 6 Questions.
ACTUAL Exam Questions and CORRECT
Answers
True or False? If the slope of the relationship between the phenotype and fitness is positive,
natural selection would decrease the phenotype over generations. - CORRECT
ANSWER - False. If the relationship is positive that phenotype would increase.
True or False? If the parameter for the squared term is negative, natural selection will likely
stabilize the phenotype at an intermediate value.
(y=ax^2+bx+c) - CORRECT ANSWER - True. (Likely being the key word. If x is
negative it will become positive when squared. But bx will continue to grow more negative.
Eventually bx will be more negative than ax^2.
What is Fitness? - CORRECT ANSWER - The relative number of viable, fertile, offspring
an organism produces.
What type of selection is most common? - CORRECT ANSWER -
True or False? Directional selection is more likely to be weak than strong. - CORRECT
ANSWER - True
True or False? Stabilizing selection occurs more often than disruptive selection. - CORRECT
ANSWER - False. They are very similar in frequency.
A researcher studied the relationship between the phenotypes of snakes and their fitness. First, he
measured the color patterns and the escape behavior of hundreds of snakes. For color pattern,
snakes were scored as being either checkered or striped (see photos below). For escape behavior,
snakes were chased by simulating a predator attack; some snakes moved in a straight line while
fleeing, but others tended to turn frequently. After recording these phenotypes, the researcher
released the snakes in their natural environment. A year later, he returned to see which snakes
had survived. The survival of snakes was used as a proxy of fitness. The figure below shows the
,relationships between color pattern and relative fitness for snakes that flee straight and snakes
that flee by turning. - CORRECT ANSWER - Info for next 5 questions.
A snake with stripes would be more likely to survive by fleeing predators in a straight line. -
CORRECT ANSWER - True
Regardless of escape behavior, the color pattern of snakes will be influenced by directional
selection. - CORRECT ANSWER - True
Over many generations, the population of snakes should evolve toward striped snakes that flee
by turning or checkered snakes that flee straight. - CORRECT ANSWER - False
The strength of selection for a color pattern is greater in snakes that flee by turning than in
snakes that flee straight. - CORRECT ANSWER - True
Although the researcher estimated fitness by survival, he could have also used another proxy for
fitness, such as mating success. - CORRECT ANSWER - True
Mitosis - CORRECT ANSWER - a type of cell division that results in two daughter cells
each having the same number and kind of chromosomes as the parent nucleus, typical of
ordinary tissue growth.
Meiosis I - CORRECT ANSWER - a cycle through which a diploid cell divides to create
two haploid cells, each receiving one of the homologous chromosomes.
Meiosis II - CORRECT ANSWER - a cycle through which the two haploid cells divide to
form four haploid cells, which later develop into sperm or eggs.
haploid cell - CORRECT ANSWER - a cell that contains a single set of chromosomes.
The term haploid can also refer to the number of chromosomes in egg or sperm cells, which are
also called gametes. In humans, gametes are haploid cells that contain 23 chromosomes, each of
which a one of a chromosome pair that exists in diplod cells.
, diploid cell - CORRECT ANSWER - A cell containing two copies of each chromosome is
referred to as a 'diploid cell'; human somatic cells are diploid: they contain 46 chromosomes, 22
pairs of autosomes and a pair of sex chromosomes.
True or False? Natural selection will likely eliminate deleterious alleles more quickly with sexual
reproduction than with asexual reproduction. - CORRECT ANSWER - True. Sexual
reproduction is faster. This causes both deleterious alleles and alleles that are beneficial to be
removed or passed on faster.
True or False? In a rapidly changing environment, a population would likely benefit more from
sexual reproduction than from asexual reproduction. - CORRECT ANSWER - True.
Rapidly changing environments require organisms to adapt faster.
True or False? If a parent passes one copy of each chromosome to offspring, alleles on the same
chromosome would be inherited together. - CORRECT ANSWER - True. The alleles are
on the same chromosome. If that chromosome is passed on then both alleles would be inherited.
True or False? If Mendel had compared traits controlled by genes on the same chromosome, his
results would not have matched the predictions of his model. - CORRECT ANSWER -
True
Use this information and your knowledge of biology to answer the following questions.
In the fruit fly, Drosophila melanogaster, a phenotype known as barred eyes sometimes appears,
in which the eyes are shaped like thin bars instead of being round. Additional crosses revealed
that a dominant allele on the X chromosome causes barred eyes. Oddly, however, the allele
arises only when two flies with normal eyes are crossed. In this case, fewer than 1% of the
offspring will have barred eyes. Male offspring never develop barred eyes. Researchers
hypothesized that the allele forms when the X chromosomes of a female cross over unequally
during meiosis, leading to one long and one short chromosome. This allele lies at a locus directly
next to a locus called B but on the opposite end of the chromosome from locus A. - CORRECT
ANSWER - Next 6 Questions.
