UCF GENETICS EXAM 1 UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Question 1
Chromosomes
Correct Answer
threadlike structures made of DNA molecules that contain the genes
Question 2
What is crossing over and when does it occur?
Correct Answer
The exchange of genes between homologous chromosomes during prophase I of
meiosis
Question 3
Two-point test vs. Three-point test
Correct Answer
The two-point test cross is done to determine the recombination frequency of two
linked genes.
The three-point cross is done to determine the order of the genes on a
chromosome and determine the distance (in map units) between each pair of
genes.
Question 4
Homozygous
Correct Answer
An organism that has two identical alleles for a trait
Page 1 of 45
,Question 5
Mutation
Correct Answer
a random error in gene replication that leads to a change
Question 6
Gametogenesis
Correct Answer
production of gametes through meiosis and other changes
Question 7
locus
Correct Answer
Location of a gene on a chromosome
Question 8
Telophase II
Correct Answer
The spindle fibres disappear, and a nuclear membrane forms around each set of
chromosomes.
Question 9
Prophase II
Correct Answer
The first phase of meiosis II. Prophase II is identical to mitotic prophase, except that
the number of chromosomes was reduced by half during meiosis I.
Page 2 of 45
,Question 10
dihybrid cross
Correct Answer
Cross or mating between organisms involving two pairs of contrasting traits
Question 11
How histones and chromatin impact gene expression
Correct Answer
- histone methylation can activate or repress gene expression
- chromatin facilitates the interactions between enhancers or other cis-regulatory
elements and their target genes or suppress gene expression by blocking the
interactions due to steric hindrance.
Question 12
sex-linked traits
Correct Answer
A trait associated with a gene that is carried only by the male or female parent.
Question 13
Recombination
Correct Answer
Process resulting in new allele combinations on a chromosome
Question 14
cytoplasmic inheritance
Correct Answer
transmission of genes that occur outside the nucleus
Page 3 of 45
, Question 15
Crossing Over
Correct Answer
Events leading to genetic recombination (chromosome breakage & exchange)
Question 16
Prometaphase
Correct Answer
The second stage of mitosis, in which the nuclear envelope fragments and the
spindle microtubules attach to the kinetochores of the chromosomes.
Question 17
Linkage
Correct Answer
Genes with loci physically located on the same chromosome
Question 18
Anaphase
Correct Answer
Phase of mitosis in which the chromosomes separate and move to opposite ends of
the cell
Question 19
lethal alleles
Correct Answer
Mutated genes that are capable of causing death.
- 2:1 ratio
Page 4 of 45
QUESTIONS AND CORRECT ANSWERS
Question 1
Chromosomes
Correct Answer
threadlike structures made of DNA molecules that contain the genes
Question 2
What is crossing over and when does it occur?
Correct Answer
The exchange of genes between homologous chromosomes during prophase I of
meiosis
Question 3
Two-point test vs. Three-point test
Correct Answer
The two-point test cross is done to determine the recombination frequency of two
linked genes.
The three-point cross is done to determine the order of the genes on a
chromosome and determine the distance (in map units) between each pair of
genes.
Question 4
Homozygous
Correct Answer
An organism that has two identical alleles for a trait
Page 1 of 45
,Question 5
Mutation
Correct Answer
a random error in gene replication that leads to a change
Question 6
Gametogenesis
Correct Answer
production of gametes through meiosis and other changes
Question 7
locus
Correct Answer
Location of a gene on a chromosome
Question 8
Telophase II
Correct Answer
The spindle fibres disappear, and a nuclear membrane forms around each set of
chromosomes.
Question 9
Prophase II
Correct Answer
The first phase of meiosis II. Prophase II is identical to mitotic prophase, except that
the number of chromosomes was reduced by half during meiosis I.
Page 2 of 45
,Question 10
dihybrid cross
Correct Answer
Cross or mating between organisms involving two pairs of contrasting traits
Question 11
How histones and chromatin impact gene expression
Correct Answer
- histone methylation can activate or repress gene expression
- chromatin facilitates the interactions between enhancers or other cis-regulatory
elements and their target genes or suppress gene expression by blocking the
interactions due to steric hindrance.
Question 12
sex-linked traits
Correct Answer
A trait associated with a gene that is carried only by the male or female parent.
Question 13
Recombination
Correct Answer
Process resulting in new allele combinations on a chromosome
Question 14
cytoplasmic inheritance
Correct Answer
transmission of genes that occur outside the nucleus
Page 3 of 45
, Question 15
Crossing Over
Correct Answer
Events leading to genetic recombination (chromosome breakage & exchange)
Question 16
Prometaphase
Correct Answer
The second stage of mitosis, in which the nuclear envelope fragments and the
spindle microtubules attach to the kinetochores of the chromosomes.
Question 17
Linkage
Correct Answer
Genes with loci physically located on the same chromosome
Question 18
Anaphase
Correct Answer
Phase of mitosis in which the chromosomes separate and move to opposite ends of
the cell
Question 19
lethal alleles
Correct Answer
Mutated genes that are capable of causing death.
- 2:1 ratio
Page 4 of 45
