1.
Who is considered the "Father of Genetics"?
Correct Answer
A. Gregor Mendel
Explanation
Gregor Mendel discovered many principles of heredity in the 1800s by working with pea plants.
2.
Which of the following is a homozygous recessive genotype?
Correct Answer
C. Tt
Explanation
A homozygous recessive genotype is one in which both alleles for a particular gene are recessive. In this case, the genotype "tt" represents two recessive alleles, while "TT" represents two dominant alleles and "Tt" represents one dominant and one recessive allele.
3.
Which of the following is a homozygous dominant genotype?
Correct Answer
A. TT
Explanation
Homozygous indicates that the alleles are the same and dominant tells us that the alleles are represented by capital letters.
4.
Which of the following is a heterozygous genotype?
Correct Answer
B. Tt
Explanation
Heterozygous means different or one of each type of allele: dominant and recessive.
5.
What happens to the chromosome number during meiosis?
Correct Answer
C. It halves.
Explanation
Meiosis cuts the number of chromosomes in the parent cell in half to produce two haploid cells.
6.
A diploid cell has _____ set(s) of homologous chromosomes.
Correct Answer
B. Two
Explanation
Di means two so the word diploid means two sets of chromosomes. Diploid cells are produced during mitosis.
7.
A haploid cell has _______ set(s) of chromosomes.
Correct Answer
A. One
Explanation
Ha refers to half so a haploid cell contains only one set of chromosomes. Gametes are haploid cells.
8.
The possible form of a gene is called a(n) _____________.
Correct Answer
D. Allele
Explanation
Mendel dubbed the different forms of gene alleles. In a monohybrid cross, the two alleles are dominant and recessive.
9.
Haploid cells are formed during the process of ____________.
Correct Answer
B. Meiosis
Explanation
Meiosis produces gametes which are haploid cells so that when a male and a female gamete meet in the process of fertilization the resulting zygote has the full number of chromosomes to produce a healthy individual.
10.
Another name for haploid cells are _________.
Correct Answer
A. Gametes
Explanation
Gametes must be haploid in order for the zygote to receive the correct number of chromosomes.
11.
The types of cells produced during mitosis are _________.
Correct Answer
B. Diploid
Explanation
Mitosis produces a cell that is exactly like the parent cell, with the full number of chromosomes.
12.
A human body cell contains 46 chromosomes. How many chromosomes does a human gamete contain?
Correct Answer
B. 23
Explanation
Gametes are haploid cells. They contain half the number of chromosomes as a normal body (somatic) cell.
13.
The gamete of a fruit fly contains 4 chromosomes. How many chromosomes does a cell from the fruit fly's wing contain?
Correct Answer
D. 8
Explanation
A gamete (egg or sperm) contains half the number of chromosomes of a cell from anywhere on the organism's body.
14.
In a monohybrid cross, when a homozygous dominant individual is crossed with a homozygous recessive individual all of the offspring will be __________.
Correct Answer
B. Heterozygous
Explanation
TT x tt = 100% Tt
15.
In a monohybrid cross, when two heterozygous individuals are crossed the genotypic ratio will be _______________.
Correct Answer
C. 1 homozygous dominant, 2 heterozygous, 1 homozygous recessive
Explanation
Tt x Tt = 1 TT: 2 Tt: 1 tt
16.
Which of the following are true of gametes?
Correct Answer(s)
A. Are formed during meiosis
B. Are haploid cells
C. Examples are eggs and sperm
F. When joined form a diploid cell
Explanation
Gametes are formed during meiosis, which is a type of cell division that produces haploid cells. Haploid cells contain half the number of chromosomes compared to the parent cell. Examples of gametes are eggs and sperm, which are reproductive cells in females and males, respectively. When gametes fuse during fertilization, they form a diploid cell, which contains the full set of chromosomes. Therefore, the statement "are formed during meiosis, are haploid cells, examples are eggs and sperm, when joined form a diploid cell" is true.
17.
A normal man has 4 daughters, 4 sons, and 12 grandchildren. A daughter and a son have inherited a certain disease but the grandchildren are unaffected. This is an example of
Correct Answer
B. Autosomal recessive
Explanation
Autosomal recessive traits are only expressed in people if they are homozygous recessive. Autosomal means that the trait is inherited regardless of gender.
18.
Both males and females have this chromosome.
Correct Answer
A. X
Explanation
All people have at least one X chromosome. XX = female XY = male
19.
Only males have this chromosome
Correct Answer
B. Y
Explanation
Females = XX
Males = XY
20.
Type of factor or gene that can be masked or hidden by a dominant one
Correct Answer
Recessive
Explanation
A recessive factor or gene is one that is not expressed or visible when a dominant factor or gene is present. This means that the dominant factor or gene "masks" or hides the recessive one, preventing it from being seen or having an effect. In order for a recessive factor or gene to be expressed, both copies of the gene must be recessive, meaning that it is inherited from both parents. If only one copy is recessive and the other is dominant, the dominant gene will be expressed and the recessive one will be masked.
21.
Number of chromosomes in the human cells
Correct Answer
forty-six
46
Explanation
The number of chromosomes in human cells is forty-six, which is also represented as 46. Chromosomes are thread-like structures that carry genetic information in the form of DNA. In humans, each cell typically contains 23 pairs of chromosomes, making a total of 46. These chromosomes determine various traits and characteristics of an individual.
22.
Most sex-linked genes are found on the
Correct Answer
D. X chromosome
Explanation
Sex-linked genes are genes that are located on the sex chromosomes, which determine the sex of an individual. The Y chromosome is responsible for determining male characteristics, while the X chromosome is responsible for determining both male and female characteristics. Therefore, it is more likely for sex-linked genes to be found on the X chromosome rather than the Y chromosome or any other chromosome.
23.
For the genotype below determine what phenotypes are possible.
Purple flowers are dominant to white flowers.
Correct Answer
C. PP=Purple, pp=White, Pp=Purple
Explanation
The genotype PP represents a homozygous dominant individual, which means they have two copies of the dominant allele for purple flowers. Therefore, their phenotype will be purple. The genotype pp represents a homozygous recessive individual, which means they have two copies of the recessive allele for white flowers. Therefore, their phenotype will be white. The genotype Pp represents a heterozygous individual, which means they have one copy of the dominant allele and one copy of the recessive allele. In this case, the dominant allele for purple flowers will determine the phenotype, so their phenotype will be purple.