Exam 3 Practice Exam
Supplemental Instruction
Iowa State University / Leader: / Jessica
Course: / Biol 211 (4)
Instructor: / Holscher
Date: / 11/6/2016
1.) What is a chromatid?
A) a chromosome in the G1 stage of mitosis
B) a replicate chromosome
C) a region that holds 2 chromosomes together
D) a structure in the cell composed of centrioles
E) extra-nuclear DNA
2.) What is a centromere?
A) a chromosome in the G1 stage of mitosis
B) a replicate chromosome
C) a region that holds 2 chromosomes together
D) a structure in the cell composed of centrioles
E) extra-nuclear DNA
3.) If there are 20 chromatids in the cell, how many centromeres are there
A) 10
B) 20
C) 40
D) 60
E) 80
4.) If a species has a 2n number of chromosomes = 10and crossing over does not occur, how many possible combinations of daughter cells could result from meiosis?
A) 20
B) 60
C) 46
D) 32
E) 24
5.) Which of the following occurs in meiosis but not mitosis?
A) chromosome replication
B) synapsis of chromosomes
C) production of daughter cells
D) alignment of chromosomes at the center of cell
E) condensation of chromatin
6.) A human cell containing 22 autosomes and a Y chromosome is a
A) egg
B)zygote
C) sperm
D) a male somatic cell
E) a female somatic cell
7.) A cross between a homozygous purple flowered and a homozygous white flowered pea plants results in offspring with purple flowers. This demonstrates
A) blending inheritance
B) true breeding traits
C) dominance of one trait over another
D) a di-hybrid cross
E) a mistake by Mendel
8.) When you cross an organism that is homozygous recessive for a trait with one that is a heterozygote for the same trait, what is the chance of producing homozygous recessive offspring?
A) 0%
B) 25%
C) 50%
D) 75%
E) 100%
9.) An organism’s appearance or observable traits are referred to as its
A) genotype
B) phenotype
C) character
D) trait
E) dominant allele
10). ______isolation is an example of a prezygotic barrier where two species of trout
breed at different seasons.
a) Gametic
b) Temporal
c) Behavioral
d) Habitat
e) Mechanical
11.) If the allele frequencies in a population are A: 0.6 and a: 0.4. what is the frequency of the Aa genotype if the population is in Hardy-Weinberg equilibrium?
A) 1.0
B) 0.52
C) 0.36
D) 0.48
12.) Using the same data what is the frequency of the AA genotype?
A) 1.0
B) 0.52
C) 0.36
D) 0.48
13.) Individuals from two lizard species can mate but the offspring are sterile. This is an example of a
A) pre-zygotic reproductive barrier
B) anatomical incompatibility
C) post-zygotic reproductive barrier
D) behavioral isolation
14.) Which of the following does not occur during the M phase of the cell cycle?
A) formation of kinetochores
B) separation of sister chromatids
C) replication of DNA
D) formation of spindle apparatus
15.) In a population in Hardy-Weinberg equilibrium, 55% of the individuals have a dominant allele and 45% of the individuals have a recessive allele for a particular gene. The proportion of homozygous recessive individuals in the F1 generation will be what?
A) 17%
B) 20%
C) 45%
D) 75%
16.) A mammalian skin cell containing 56 chromatids at the start of the M phase of the cell cycle will eventually produce ____ nuclei that each contain ____ chromosomes at the completion of the cell cycle.
A) 2…56
B) 2…28
C) 4…56
D) 4…28
17.) The first step in allopatric speciation is
A) mutation
B) polyploidy
C) genetic drift
D) geographic isolation
18.) Two parents have a child. One parent is heterozygous for the trait, and one has blonde hair. Blonde hair color is a recessive trait. What is the probability that their child will have blonde hair? What is the probability that their child will be a carrier for blonde hair? (hint: Punnett square!)
A) 25% carrier 75% blonde
B) 75% carrier 25% blonde
C) 50% carrier 50% blonde
D) 55% carrier 45% blonde
19.) Your cat decides to mate with a cat with long fur (Ff) and brown eyes (Bb). How many different types of gametes can this cat produce? What are they?
A) 4 different types, FB, Fb, fB, and fb
B) 2 different types, FB and fb
C) 1 different type, FB
D) 2 different types, fB and Fb
20.) In a particular animal species, a long tail (T) is dominant to a short tail (t), and black hair (B) is dominant to brown hair (b). When a TtBb female is mated with a Ttbb male, the observed distribution of offspring is as follows: 737 offspring with a long tail and black hair, 345 offspring with a long tail and brown hair, 124 offspring with a short tail and black hair, and 872 offspring with a short tail and brown hair. Based on these offspring, what is the approximate recombination frequency?
A) 79%
B) 36%
C) 48%
D) 54%
21.) A plant that has the genotype Aabbcc
A) is triploid
B) is homozygous at two loci
C) is heterozygous at two loci
D) has dominant alleles at three loci
22.) Who was the first scientist to prove that genes are located on specific chromosomes?
A) Thomas Hunt Morgan
B) Walter Sutton
C) Gregor Mendel
D) Nettie Stevens
23.) What is a monohybrid cross?
A) cross between 2 organisms examining 2 traits
B) cross between 2 organisms examining 1 trait
C) cross between 1 organism examining 2 traits
D) cross between 1 organism examining 1 trait
24.) What is a dihybrid cross?
A) cross between 2 organisms examining 2 traits
B) cross between 2 organisms examining 1 trait
C) cross between 1 organism examining 2 traits
D) cross between 1 organism examining 1 trait
25.) A situation in which a chromosome number can be represented as 2n+1 or 2n-1 is called?
A) inversion
B) polyploidy
C) aneuploidy
D) gene linkage
26.) What stage is missing during Meiosis II
A) metaphase
B) prophase
C) interphase
D) telophase
27.) Meiosis results in the formation of how many daughter cells?
A) 2
B) 3
C) 4
D) 8
28.) What is a theory?
A) same as a hypothesis
B) idea that hasn’t been tested yet
C) idea that may or may not be true
D) a hypothesis that has been tested and is well supported by data
29.) The precise location of a gene on a chromosome is known as its
A) loci
B) trait
C) sequence
D) character
30.) The frequency with which crossing over occurs between any two linked genes is ____
A) the same as if they were not linked
B) different between males and females
C) determined by their relative dominance
D) proportional to the distance between the genes
31.) A single gene that influences many genes is said to be
A) autosomal
B) pleiotropic
C) multitropic
D) codominant
32.) During meiosis, homologous chromosomes sometimes “stick together” and do not separate properly. This disorder is known as
A) meiotic failure
B) nondisjunction
C) cellular sterility
D) gamete infertility
33.) Prezygotic isolating mechanisms
A) impede members of different species from attempting to mate
B) prevent the hybrid zygote from developing into a viable, fertile offspring
C) increase the probability of fertilization if mating is completed successfully
D) increase the number of successfully completely matings between members of different species
34.) A process in which individuals that have certain heritable characteristics survive and reproduce at a higher rate than other individuals is known as
A) homology
B) catastrophism
C) natural selection
D) uniformitarianism
35.) Which of the following scientists developed a theory of evolution that was very similar to Charles Darwin’s?
A) James Hutton
B) Alfred Wallace
C) Georges Cuvier
D) Jean-Baptiste de Lamarck
36.) What is an allele?
A) type of chromosome
B) recessive form of gene
C) dominant form of gene
D) variant form of gene
37.) A mammalian cell entering the M phase of the cell cycle contains 50 chromosomes. How many chromatids does it contain?
A) 1
B) 25
C) 46
D) 100
38.) Where do the microtubules of the spindle apparatus originate during mitosis?
A) the centromeres
B) the centrosomes
C) the kinetochore
D) the cleavage furrow
39.) The most common phenotype in the population is called
A) wild type
B) geneotype
C) autosome
D) mutant phenotype
40.) What is an autosome?
A) dominant trait
B) another name for a sex chromosome
C) any chromosome that is not a sex chromosome
D) recessive trait
41.) The reason that linked genes are inherited together is because
A) the alleles are paired
B) the chromosomes are unbreakable
C) the genes are located on the same chromosome
D) the number of genes in a cell is greater than the number of chromosomes
42.) How are new alleles formed?
A) interbreeding
B) breeding with members of a different population
C) mutation
D) recombination of genes
43.) What is the founder effect?
A) when a group of individuals immigrates to a new area and establishes a new population
B) when a sudden environmental change drastically reduces the size of the population
C) when individuals leave one population, join another, and breed
D) random genetic drift with respect to fitness
44.) What is genetic bottleneck?
A) when a group of individuals immigrates to a new area and establishes a new population
B) when a sudden environmental change drastically reduces the size of the population
C) when individuals leave one population, join another, and breed
D) random genetic drift with respect to fitness
45.) What is the equation for allele frequency?
A) p2 + 2pq + a2 = 1
B) p + q = 1
C) 2p + 2pq + 2q = 1
D) 2pq = 1
46.) What is the equation for genotype frequency?
A) p2 + 2pq + a2 = 1
B) p + q = 1
C) 2p + 2pq + 2q = 1
D) 2pq = 1
47.) What does q stand for in the equations above?
A) frequency of dominant allele in population
B) frequency of recessive allele in population
C) frequency of heterozygous individuals in population
D) frequency of homozygous recessive individuals in population
48.) What does p stand for in the equations above?
A) frequency of dominant allele in population
B) frequency of recessive allele in population
C) frequency of heterozygous individuals in population
D) frequency of homozygous recessive individuals in population
49.) What does mitosis result in?
A) 2 identical daughter cells
B) 4 identical daughter cells
C) 2 nonidentical daughter
D) 4 nonidentical daughter cells
50. What does meiosis result in?
A) 2 identical daughter cells
B) 4 identical daughter cells
C) 2 nonidentical daughter
D) 4 nonidentical daughter cells
Good luck on your exam Tuesday!
Email me at if you have any questions before the exam.
NO SESSION TUESDAY (11/8).