Chapter 3 Genetics IB-2 SL IC
Choose the correct answer.
a.
b.
c.
d.
1. The locus of a gene is:
An alternative form of a gene coding for a particular trait
The location of a specific gene on a chromosome
The larger bottom arm of a chromosome
The shorter top arm of a chromosome
2.
Which of these best describes a gene?
1. Genes are only found in somatic cells
2. Genes cannot be passed on to future generations
3. Genes are heritable factors that code for a specific trait
4. Genes are only found on the sex chromosomes
3.
Which of these best describes an allele?
1. An alternative form of a gene that codes for different variations of a trait
2. An exact copy of a gene that codes for the same trait
3. The location of a specific gene on a chromosome
4. Alleles are only found on the sex chromosomes
4.
Label the parts of a chromosome:
A
A.
B.
B
D
A
C
C.
D.
5.
Name the three different types of a gene mutation (3).
6. Sickle cell anemia can be characterized by with of the following? Select all that apply.
a.
b.
c.
d.
Red blood cells are misshapen and cannot carry oxygen as efficiently
Sickle cells are destroyed more rapidly than normal cells, leading to low red blood cell count.
Sickle cell anemia is due to a bacterial infection, and can be treated with the use of antibiotics
Sickle cell anemia arises from a change in amino acids, from glutamine to valine
7. Which of the following is true about an organism’s genome? Select all that apply.
a. The genome consists of the totality of an organism’s genes
b. The number of genes present in an organism is an indicator of its biological complexity
c. The number of genes in the human genome is estimated to be 50,000-60,000 genes
d. Mapping an organism’s genome can help scientists identify genes of interest to study
8.
Which chromosome(s) determine the sex of an offspring in humans?
1. X chromosome
2. X and Y chromosomes
3. X and X chromosomes
4. Y chromosome
9.
Cats have 38 chromosomes in their diploid cells (2n=38). How many chromosomes do they have in their
gametes?
a. 38
b. 76
c. 19
d. 36
10.
What is the difference between the ultimate goal of mitosis and meiosis? (2)
11.
Name the three ways genetic variation is created/maintained during meiosis. (3)
12.
Nondisjunction is when:
a.
Chromosomes fail to separate correctly
Chromosomes exchange genetic material
c.
Chromosomes duplicate
d.
2 daughter cells divide into 4 daughter cells
b.
13.
During which phase of meiosis are sister chromatids separated?
1. Metaphase I
2. Anaphase I
3. Telophase II
4. Anaphase II
Use the karyotype below to answer the following questions:
a.
What sex is this a karyotype of?
b.
What genetic disorder is shown in the karyotype?
c.
What is the proper notation for this disorder?
14.
Gregor Mendel is responsible for discovering:
1. The shape and structure of DNA
2. The cell theory of biology
3. Evolution through natural selection
4. The principles of inheritance
15.
How many alleles of each gene are contained in a daughter cell after meiosis?
1. 1
2. 2
3. 4
4. 8
16.
If you wanted to determine the phenotype of an organism, what procedure would you follow?
1. DNA sequence the parents
2. DNA fingerprint the organism using gel electrophoresis
3. Look at the physical characteristics of the organism
4. Do a hybrid cross
17.
4 dogs were born with the following genotypes:
BB - Black dog
Bb- Black dog
bB- Black dog
bb - Brown dog
a.
c.
Which of the following best describes the type of inheritance regarding the dogs’ colors?
Complete dominance
b.
Incomplete dominance
Codominance
d.
Hemidominance
18.
Explain why O blood groups are known as universal donors. (2)
19.
Why are autosomal recessive diseases less likely than autosomal dominant to lead to disease symptoms ?
1. Heterozygous individuals possess one copy of the gene, and so will display symptoms
2. Autosomal recessive diseases require only one copy of the faulty gene to display symptoms
3. Autosomal recessive diseases require two copies of the faulty gene to display symptoms
4. None of the above
20.
Populations that live closer to the equator tend to have darker skin because:
1. Lower melanin content has evolved as an adaptive protection against higher UV radiation
2. Higher melanin content has evolved as an adaptive protection against lower UV radiation
3. Higher melanin content has evolved as an adaptive protection against higher UV radiation
4. None of the above
21.
Polymerase chain reaction (PCR) is a laboratory technique used to:
1. Separate DNA and proteins by size
2. Replicate large quantities of DNA
3. Separate DNA from solution through high centrifugal force
4. Successfully propagate plants from stem cuttings
22.
Explain what gives DNA its electrical charge, and explain how DNA’s electrical charge determines in which
direction it will move during gel electrophoresis. (3)
23.
Gel electrophoresis is a laboratory technique that can be used for which of the following? Select all that apply.
1. Separating DNA and proteins by size
2. Forensic DNA profiling from DNA collected at a crime scene
3. Determining the paternity of a child
4. Replicating large quantities of DNA
24.
Which of the following are potential benefits of genetically modified organisms?
1. GM crops can be modified to resist pesticides, allowing for the easier killing of weeds
2. GM crops can be modified to produce higher yields, thus helping to feed more people
3. GM crops can be modified to increase their nutritional value
4. All of the above
25.
Recombinant plasmids can be used to do which of the following?
1. Express desired traits of a specific gene
2. Produce viruses
3. Destroy vectors
4. All of the above
26.
The following is an example of which type of animal cloning?
a.
b.
c.
d.
Fragmentation
Budding
Binary fission
Parthenogenesis
In sickle cell disease there are two alleles for the protein hemoglobin. These are called HbS and HbA . What is thought to
be the cause of the existence of the Hb allele?
A. An infection
B. Protein synthesis
C. A mutation
D. DNA replication
What was it that the Human Genome Project's international consortium achieved in 2003 when they
announced the successful completion of the Human Genome Project?
A. They had found the function of all human genes.
B. They had found the sequence of all amino acids in all human proteins
C. They had sequenced the entire base sequence of human genes
D. They had sequenced the DNA bases of all known genes
In the rat genome sequencing project of 2004, Dr Richard Gibbs and his researchers reported that the rat
genome is smaller than the human genome, and slightly larger than mouse genome. H owever, they also
found that the rat genome contains about the same number of genes as the human and mouse genomes.
Species
Human
Rat
Mouse
Genome size
2.9 billion base pairs
2.75 billion base pairs
2.6 billion base pairs
Estimated gene number
20000 to 30000
20000 to 30000
20000 to 30000
Chromosome number
46
42
40
Which of the following suggestions could be an explanation for such a large difference in the genome size of
these three species when the number of genes is thought to be so similar?
A. Most of the differences in the genome size are found in non-coding regions of the DNA, where there are no
genes.
B. Humans have more chromosomes, and therefore more DNA base pairs
C. The differences are smaller than the precision of the method, so are not significant differences.
D. The genes in humans have a longer length
27.
Use the pedigree below to answer the following questions:
How many generations are shown in this pedigree?
What is the most likely form of inheritance for this pedigree?
State the genotypes of individuals # 6-8 in the following table using the letter ”A”. Use the uppercase letter to represent
the dominant allele and lowercase letter to represent the recessive allele
Individual Genotype
#6
#7
#8
If individuals #6 and #7 have another child, what are the chances it will be affected?
28. A woman who is a carrier (heterozygous) for Cystic Fibrosis marries a man who has Cystic Fibrosis, a
recessive disease.
a) What are the genotypes?
b) What is the probability that their children will have the disease?
c) What is the probability that their children will not have the disease?
(Show a Punnett square showing the phenotypic and genotypic ratios)
29. Compare and contrast the chromosomes of a prokaryote and eukaryote.
Prokaryote Chromosomes Eukaryote Chromosomes
DNA Structure
Shape of chromosomes
Number of chromosomes
Location
Contains plasmids?
Yes or no
Discuss briefly the following questions.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
State the principle of independent assortment below
What is probability?
State the principle of dominance.
List 5 main differences between meiosis and mitosis.
Define meiosis.
Is the DNA replicated after meiosis I? Why or why not?
What are two ways I can obtain cells to perform a karyotype.
Explain how sickle cell anemia can protect against malaria.
What are polygenic genes? Give an example.
Construct a table showing the pros and cons of cloning.
What id DNA fingerprinting? What are its uses?
Describe the main difference between metaphase I and metaphase II.
State the phase where each of the following processes occurs:
(a) sister chromatids separate,
(b) homologous chromosomes form pairs,
(c) two haploid cells form.
14. What is final product of meiosis?
15. How did Mendel cross-pollinate flowers?
16. Why are peas a good model system for studying heredity?
17. What is segregation? What is the result of the following segregation?
BB
Brown eyes
bb
parents
blue eyes
Gametes
F1 generation
Additional Multiple-Choice Questions.
This produces 2 identical cells.
a) mitosis
b) meiosis
The cells produced via meiosis are called:
a)
b)
c)
d)
sex cells
somatic cells
body cells
skin cells
A human usually has xx amount of chromosomes.
a)
b)
c)
d)
6
22
4
46
Q. What is it called when a sperm and egg meet?
a) meiosis
b) fertilization
c) cell division
d) mitosis
The end of meiosis results in ________ to each other.
a)
b)
c)
d)
2 cells that are identical
4 cells that are identical
2 cells that are not identical
4 cells that are not identical
This produces sex cells.
a) mitosis
b) meiosis
What phase is shown in the picture?
a)
b)
c)
d)
anaphase 1
anaphase 2
metaphase 1
telophase 1
This produces 2 identical cells.
a) mitosis
b) meiosis
Meiosis makes sperm and egg cells. In humans, sperm and egg cells each have _____ chromosomes. Therefore
a fertilized human egg cell (sperm and egg cell combined) would create a cell with _____ chromosomes.
a)
b)
c)
d)
23, 46
46, 23
2, 4
50, 100
What causes genetic variation in meiosis?
a)
b)
c)
d)
chromosomes lining up
crossing over of chromosomes
separation of chromosomes
chromosomes pulling apart
Unlike mitosis, meiosis in male mammals results in the formation of
a) one haploid gamete
b) three diploid gametes
c) four diploid gametes
d) four haploid gametes
What happens to the chromosome number during meiosis?
a)
b)
c)
d)
It doubles
It stays the same
It divides in half
It becomes diploid
During which phase of meiosis is the chromosome number reduced?
a)
b)
c)
d)
anaphase I
metaphase I
telophase I
telophase II
The process of mitosis and cytokenesis produce two two idenetical...
a)
b)
c)
d)
daughter cells
strands
chromosomes
chromatids
When an area of a chromatid is exchanged with the matching area on a chromatid of its homologous chromosome,
_________________ occurs
a)
b)
c)
d)
crossing over
mutagenesis
hybridization
fertilization
Cells containing two alleles for each trait are described as
a)
b)
c)
d)
haploid
heredity
diploid
homozygous
Q. Haploid Cells are represented by
a)
b)
c)
d)
2n
n
1/2 n
4n
What kind of cells are made in MEIOSIS?
a)
b)
c)
d)
Haploid Gametes
Diploid Somatic Cells
Skin Cells
Liver Cells
Meiosis results creates special cells called gametes that have exact copies of the parents cells genetic material
a) true
b) false
In which stage of meiosis I do the homologous chromosomes move to opposite poles of the cell?
a)
b)
c)
d)
Anaphase
Prophase
Metaphase
Telophase
In Metaphase I, the ______ align in the middle of a cell.
a)
b)
c)
d)
homologous chromosomes
sister chromatids
sister chromosomes
homologous chromatids
The two sister chromatids are a part of a _____.
a)
b)
c)
d)
Centromere
Multichromatic
Dihyrbid
Chromosome
During meiosis, one _____ cell divides and makes _____ sex cells.
a)
b)
c)
d)
haploid/diploid
diploid/haploid
homologous/heterozygous
heterozygous/homologous
When homologous chromosomes match up, they form a structure call a ___________.
a)
b)
c)
d)
tetrad
triad
diploid
gamete
A human zygote should have _____ chromosomes inside.
a)
b)
c)
d)
46
23
92
64
What phase is represented?
a)
b)
c)
d)
metaphase 1
metaphase 2
anaphase 1
anaphase 2
When Gregor Mendel crossed a tall plant with a short plant, the F1 plants inherited
a)
b)
c)
d)
one allele from each parent.
two alleles from each parent.
three alleles from each parent.
four alleles from each parent.
The principles of probability can be used to
a)
b)
c)
d)
predict the traits of the offspring of genetic crosses.
determine the actual outcomes of genetic crosses.
determine which species should be used in genetic crosses.
decide which organisms are best to use in genetic crosses.
A segment of DNA that codes for a trait
a)
b)
c)
d)
gene
centromere
chromosome
chromatid
An observable characteristic
a)
b)
c)
d)
trait
personality
cell
DNA
A version or variation of a gene
a)
b)
c)
d)
trait
gene
allele
DNA
The alleles that an organism has/inherits are its
a)
b)
c)
d)
genotype
phenotype
chromosome
recessive
The observable expression of a trait is its
a)
b)
c)
d)
phenotype
genotype
chromosome
allele
When an organism has two of the same alleles, it is called
a)
b)
c)
d)
homozygous
heterozygous
recessive
dominant
______ is the set of genes possessed by someone
a)
b)
c)
d)
Karyotype
Fingerprint
Genotype
Phenotype
Humans have _______ pairs of chromosomes, for a total of _______ chromosomes.
a)
b)
c)
d)
10, 20
25, 100
23, 46
46, 92
The Law of Segregation states that alleles separate during the process of ...
a)
b)
c)
d)
Mitosis
Meiosis
Fertilization
Replication
Which of Mendel's laws states that alleles are distributed to gametes independent of one another?
a)
b)
c)
d)
Law of Dominance
Law of Segregation
Law of Independent Assortment
Law of Meiosis
What do the letters inside the grid of a Punnett square represent?
a) phenotypes of parents
b) genotypes of offspring
c) testcrosses of offspring
d) chromosomes of parents
What is the probability that a homozygous DOMINANT parent and a homozygous recessive parent will
have heterozygous offspring?
a)
b)
c)
d)
0%
25%
50%
100%
Which of Mendel's laws states that alleles are separated during meiosis?
a)
b)
c)
d)
Law of Dominance
Law of Segregation
Law of Independent Assortment
Law of Meiosis
Q. The letters on the TOP AND SIDE of a punnett square represent ______________.
a)
b)
c)
d)
The combination of alleles in offspring.
The possible alleles given by the parents following meiosis.
The genotype and phenotype of offspring.
The results of genetic mutations in offspring.
What gamete possibilities could come from this parent's genotype?
a)
b)
c)
d)
AB, AB, aB, aB
Ab, AB, Ab, ab
Ab, Ab, Ab, Ab
AB, aB, ab, aB
A scientist is observing pea plant seed color. This data will be used to predict future offspring. What tool should be used
to show the data being tracked?
a)
b)
c)
d)
Monohybrid
Dihybrid
Pedigree
Graph
What is the phenotypic ratio of a cross between two guinea pigs who are heterozygous for black fur and (Bb).
a) 9:3:3:1
b) 3:1
c) 0:8:0:8
d) 1:2:1