BIO 182 cog books M3 + M4
Study online at https://quizlet.com/_hmiobk
1. True or False? If the slope of the relationship between the phenotype and
fitness is positive, natural selection would decrease the phenotype over gener-
ations.: False. If the relationship is positive that phenotype would increase.
2. 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): 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.
3. What is Fitness?: The relative number of viable, fertile, offspring an organism produces.
4. What type of selection is most common?:
5. True or False? Directional selection is more likely to be weak than strong.: True
6. True or False? Stabilizing selection occurs more often than disruptive selec-
tion.: False. They are very similar in frequency.
7. 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.: Info for next 5 questions.
8. A snake with stripes would be more likely to survive by fleeing predators in a
straight line.: True
9. Regardless of escape behavior, the color pattern of snakes will be influenced
by directional selection.: True
10. Over many generations, the population of snakes should evolve toward
striped snakes that flee by turning or checkered snakes that flee straight.: False
11. The strength of selection for a color pattern is greater in snakes that flee by
turning than in snakes that flee straight.: True
, BIO 182 cog books M3 + M4
Study online at https://quizlet.com/_hmiobk
12. Although the researcher estimated fitness by survival, he could have also
used another proxy for fitness, such as mating success.: True
13. Mitosis: 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.
14. Meiosis I: a cycle through which a diploid cell divides to create two haploid cells, each receiving one of the
homologous chromosomes.
15. Meiosis II: a cycle through which the two haploid cells divide to form four haploid cells, which later develop
into sperm or eggs.
16. haploid cell: 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.
17. diploid cell: 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.
18. True or False? Natural selection will likely eliminate deleterious alleles more
quickly with sexual reproduction than with asexual reproduction.: True. Sexual repro-
duction is faster. This causes both deleterious alleles and alleles that are beneficial to be removed or passed on faster.
19. True or False? In a rapidly changing environment, a population would likely
benefit more from sexual reproduction than from asexual reproduction.: True.
Rapidly changing environments require organisms to adapt faster.
20. True or False? If a parent passes one copy of each chromosome to offspring,
alleles on the same chromosome would be inherited together.: True. The alleles are on
the same chromosome. If that chromosome is passed on then both alleles would be inherited.
21. 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.: True
22. 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
Study online at https://quizlet.com/_hmiobk
1. True or False? If the slope of the relationship between the phenotype and
fitness is positive, natural selection would decrease the phenotype over gener-
ations.: False. If the relationship is positive that phenotype would increase.
2. 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): 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.
3. What is Fitness?: The relative number of viable, fertile, offspring an organism produces.
4. What type of selection is most common?:
5. True or False? Directional selection is more likely to be weak than strong.: True
6. True or False? Stabilizing selection occurs more often than disruptive selec-
tion.: False. They are very similar in frequency.
7. 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.: Info for next 5 questions.
8. A snake with stripes would be more likely to survive by fleeing predators in a
straight line.: True
9. Regardless of escape behavior, the color pattern of snakes will be influenced
by directional selection.: True
10. Over many generations, the population of snakes should evolve toward
striped snakes that flee by turning or checkered snakes that flee straight.: False
11. The strength of selection for a color pattern is greater in snakes that flee by
turning than in snakes that flee straight.: True
, BIO 182 cog books M3 + M4
Study online at https://quizlet.com/_hmiobk
12. Although the researcher estimated fitness by survival, he could have also
used another proxy for fitness, such as mating success.: True
13. Mitosis: 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.
14. Meiosis I: a cycle through which a diploid cell divides to create two haploid cells, each receiving one of the
homologous chromosomes.
15. Meiosis II: a cycle through which the two haploid cells divide to form four haploid cells, which later develop
into sperm or eggs.
16. haploid cell: 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.
17. diploid cell: 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.
18. True or False? Natural selection will likely eliminate deleterious alleles more
quickly with sexual reproduction than with asexual reproduction.: True. Sexual repro-
duction is faster. This causes both deleterious alleles and alleles that are beneficial to be removed or passed on faster.
19. True or False? In a rapidly changing environment, a population would likely
benefit more from sexual reproduction than from asexual reproduction.: True.
Rapidly changing environments require organisms to adapt faster.
20. True or False? If a parent passes one copy of each chromosome to offspring,
alleles on the same chromosome would be inherited together.: True. The alleles are on
the same chromosome. If that chromosome is passed on then both alleles would be inherited.
21. 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.: True
22. 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
