Download Worksheet 4.5 (Practice Exam 4)

Leader: Hannah
Course: BIOL 211 (2)
Instructor: Dr. Waldman
Supplemental Instruction
Iowa State University
Date: 03/26/15
**Look at book questions and Mastering Biology for extra practice!!
Exam 4 Review (Practice Exam 4)
Worksheet 4.5
1.) Which of the following is NOT one of the purposes mitosis serves?
a. Wound repair
b. Growth
c. Replace lost cells due to normal wear and tear
d. All the above are purposes of mitosis
2.) Which of the following is the correct order for the phases of the cell cycle
a. G1, G2, S, and M
b. S, G2, M, and G1
c. S, G1, M, and G2
d. S, G2, G1, and M
3.) A certain species of animal has 6 pairs of chromosomes. How many sister chromatids
do the nuclei of these animals have during G2 phase?
a. 6
b. 12
c. 24
d. 48
4.) Label the parts of the following figure: chromosome, centromere, chromatid, sister
chromatids, homologous chromosomes
5.) During mitosis, it is necessary for the nuclear envelope of the parent cell to disintegrate.
If the enzyme responsible for that phosphorylation event is inhibited, at which phase of
mitosis are cells likely to arrest?
a. Telophase
b. Prophase
c. Prometaphase
d. Anaphase
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6.) Compare the events that occur during mitosis and both meiosis I and II.
Mitosis
Meiosis I
Meiosis II
Prophase
Prometaphase
Metaphase
Anaphase
Telophase &
Cytokinesis
7.) Which of the following conditions will most likely prevent a cell from passing the G1
checkpoint?
a. Nutrients are adequate
b. The cell has received social signals from other cells
c. DNA is damaged
d. The cell has reached a certain minimum size
8.) Many cancers are due to the failure of cells to properly regulate the _______ checkpoint
during the cell cycle.
a. Metaphase (M)
b. G2
c. G1 (commits the cell to dividing or into non-dividing stage—G0); controls
division rate
d. Cancer is not caused by the inability to regulate a checkpoint
9.) Which of the following statements regarding tumors is correct?
a. Benign tumors are noninvasive and noncancerous
b. Malignant tumors are noninvasive and noncancerous
c. Both types of cancers are noninvasive and noncancerous
d. None of the above are correct
10.) Some plants are triploid. If a plant has a haploid chromosome number of 42, how many
chromosomes are present in its somatic cells?
a. 84
b. 42
c. 21
d. 126
11.) Which of the following statements best describes a phase that occurs in meiosis II?
a. Tetrads migrate to the metaphase plate?
b. Homologous chromosomes separate and begin moving to opposite sides of the
cell
c. Sister chromatids separate and begin moving to opposite sides of the cell
d. Crossing over of non-sister chromatids occurs
12.) Crossing over occurs _____________.
a. Very rarely; not every homologous pair of chromosomes is able to exhibit
crossing over
b. Between chromatids of homologous chromosomes
c. During prophase II of meiosis
d. Between sister chromatids on the same chromosome
13.) Where does crossing over specifically occur?
a. Chiasma
b. Centromere
c. Kinetochore (proteins closely association w/ centromere; help bind chromos.)
d. None of the above
14.) True or False: Chromosomes that result from crossing over have a mixture of paternal
and maternal alleles.
15.) What is the end result of meiosis and the subsequent fertilization of gametes?
a. An offspring with a chromosome complement identical to the paternal cell
b. An offspring with a chromosome complement identical to that of the parents
c. An offspring with a chromosome complement unlike that of either parent
d. An offspring with half the number of chromosomes of the parental cells
16.) An individual plant that exhibits self-fertilization can produce offspring different from
itself primarily as a result of ________________.
a. Solely crossing over during the formation of spores
b. Independent assortment and crossing over during the formation of spores
c. Mutations that occur during mitosis
d. The fact that the number of chromosomes in sperm is always different from the
number of chromosomes in egg cells
17.) What conclusion can be drawn from John Maynard Smith’s mathematical model
comparing sexual and asexual reproduction?
a. Sexual reproduction is always more successful than asexual reproduction
b. Asexual reproduction is always more successful than sexual reproduction
c. Asexual organisms generally produce twice as many offspring than sexually
reproducing organisms
d. Organisms produced by sexual reproduction are more variable than those
produced by asexual reproduction
18.) Name and describe the two existing hypotheses for unraveling the paradox of sex.
 1) Purifying selection hypothesis
o Natural selection against deleterious alleles (an allele that functions
poorly and lowers the fitness of an individual) = purifying selection
o Reduce numerical advantage of asexual reproduction over time
(damaged DNA is selected against)
 So if M with normal copies of the gene and F w/ normal and
deleterious allele, only half of offspring have allele
 2) Changing environment hypothesis
o Genetically variable offspring are more likely to survive in a changing
environment (offspring that are genetic clones of their parents are
unlikely to thrive if the environment changes)
o If offspring are genetically varied, then its likely that at lease some
offspring will have combinations of alleles that enable them to fight off the
new strain of pathogen or parasite & then reproduce
19.) Which of the following does NOT produce genetic variability?
a. Crossing over
b. Independent assortment
c. Outcrossing
d. Dependent assortment
20.) Some males have an abnormal karyotype consisting of 47 chromosomes with an extra Y
chromosome. This condition is most likely caused by ___________.
a. Nondisjunction in the production of the male gamete
b. Nondisjunction in the production of the female gamete
c. It is impossible to determine the most likely cause
d. Nondisjunction in the production of either the male or female gamete
21.) ____________ results when a zygote is 2n – 1 whereas ___________ results when a
zygote is 2n + 1.
a. Trisomy; Monosomy
b. Disomy; Trisomy
c. Monosomy; Trisomy
d. Monosomy; Disomy
22.) Use the picture below to answer the following questions. Haploid = # of pairs
a. Is this organism a male or a female? Male
b. How many pairs of autosomes does this organism have? 3
c. How many pairs of sex chromosomes does this organism have? 1
d. What is the haploid number of this organism? Diploid number? 4; 8
23.) True or False: When Mendel conducted his experiments, he knew about mitosis and
meiosis. (knew nothing about ploidy, chromosomes, homologous pairs, indep assort.)
24.) Which of the following is NOT true about model organisms?
a. Exhibit a short reproductive cycle
b. Exhibit traits that are easily recognizable
c. Easy to control their mating
d. Difficult to recognize traits of interest
25.) An organism’s phenotype is ___________.
a. The result of the blending of its parents’ phenotypes
b. The physical traits exhibited by the organism
c. Its entire genetic makeup
d. The alleles found in an individual
26.) When Mendel conducted his experiments, he made 3 important choices. Which of the
following is NOT one of these choices?
a. Chose to look at categorical traits
b. Used a vertebrate to carry out his experiments
c. Used pure lines
d. Had the model organism produce 3 generations
27.) An allele is ___________.
a. A specific observable characteristic of an individual
b. A hereditary factor that influences a particular trait
c. A specific form of a gene
d. A position or location of a gene on a chromosome
28.) Name and define the 2 existing hypotheses to Mendel’s questions (why do offspring
resemble their parents, and how does transmission of traits occur?).
 1) Blending inheritance hypothesis
o Parental traits blend such that offspring have intermediate traits
o E.g. parent 1 red petals, parent 2 white petals, offspring pink petals
 2) Inheritance of acquired characteristics hypothesis
o Parental traits modified and passed on to offspring
o E.g. father works out and builds muscle; offspring have muscle too
29.) What is the difference between homozygous and heterozygous?
 Homozygous2 copies of the same allele (RR or rr)
 Heterozygous 2 different alleles (Rr)
30.) What is the difference between a monohybrid and a dihybrid cross?
 Monohybrid cross = cross pollination (collect pollen from an individual and
transfer to female organs of plant with male organs removed) in PURE
lines, differ in a SINGLE trait
 Dihybrid cross = cross pollination in PURE lines, differ in TWO traits
31.) If the first five seeds (offspring) grown from a cross between 2 heterozygous parent peas
with the genotype Rr are all round, what is the probability that the next offspring from
these parents will be wrinkled?
a. 0%
b. 100%
c. 25% (1:2:1 genotype, 3:1 phenotype; do Punnett square)
d. This cannot be determined from the information given
32.) What is the frequency of each phenotype in the F2 generation of a cross between 2
homozygous parent peas with the genotypes RR and rr?
a. 1 round, 2 slightly wrinkled, and 1 wrinkled
b. ¼ RR, ½ Rr, and ¼ rr
c. 3 round, 1 wrinkled
d. 1:1:1:1
33.) If an F1 plant with the genotype RrYy self-fertilizes, what is the phenotypic ratio of the
F2 generation? (Keep in mind that R is the dominant allele for seed shape (round), r is the
recessive allele for seed shape (wrinkled), Y is the dominant allele for seed color
(yellow), and y is the recessive allele for seed color (green)).
a. 9 round, yellow: 3 round, green: 3 wrinkled, yellow: 1 wrinkled, green
b. 3 green, wrinkled: 1 yellow, round
c. 3 green: 1 yellow
d. All of the peas would be round and yellow
34.) What is a testcross?
 Dominant phenotype (genotype can be RR or Rr) crossed with recessive
phenotype (genotype must be rr)
 Use to figure out if organism is hetero or homozygous (if homo, all will be
dominant phenotype); (if hetero, half dom pheno and half rec pheno).
35.) True or False: Crossing over is more likely when genes are far apart.
36.) In four-o’-clocks, RR flowers are red, rr flowers are white, and flower color
demonstrates incomplete dominance. In a cross between RR and rr, what color flowers
are the F1 progeny going to be?
a. All red
b. All hite
c. All pink
d. Half red, half white
37.) What is a pedigree?
 A family tree to analyze human cross
 Record genetic relationship of family members, gender, & phenotype
 Reveal patterns of inheritance for genes underlying traits