Genetics Test Revision

Question 1

Where is DNA found and why is it important?

Answer 1

DNA is found in the nucleus and contains the genetic information for an organism’s growth and development.

Question 2

Explain how DNA, Chromosomes and Genes are interrelated.

Answer 2

Chromosomes carry DNA in cells. DNA is responsible for building and maintaining your human structure. Genes are segments of your DNA, that give you the physical characteristics that make you unique. They work together to make you who you are.

Question 3

Describe the structure of DNA.

Answer 3

DNA is like a twisted ladder. The phosphate and sugar on the sides of the DNA make up the sugar-phosphate backbone. Strong covalent bonds hold the sugar of one nucleotide to the phosphate of the next. These paired strands coil up into a double helix.

Question 4

What is a chromosome?

Answer 4

Chromosomes are DNA packaged tightly into thread-like structures and coiled many times around proteins called histones.

Question 5

What is a homologous chromosome?

Answer 5

Homologous chromosomes contain the same type of genetic information. One chromosome comes from the male parent and the other from the female parent.

Question 6

What is a diploid cell?

Answer 6

Contain two sets of chromosomes and undergo mitosis.

Question 7

What is a haploid cell?

Answer 7

Contain only one set of chromosomes - undergo meiosis.

Question 8

What is a karyotype?

Answer 8

The general appearance of a complete set of chromosomes in the cells of a species.

Question 9

What are the phases of mitosis?

Answer 9

Interphase, Prophase, Metaphase, Anophase, and Telophase/Cytokinesis.

Question 10

What happens in interphase during Mitosis?

Answer 10

Preparation for mitosis through cell growth, DNA replication

Question 11

What happens in prophase during Mitosis?

Answer 11

The nuclear membrane disintegrates, chromosomes condense and become visible, mitotic spindle begins to form.

Question 12

What happens in Metaphase during Mitosis?

Answer 12

Chromosomes line up in the middle of the cell.

Question 13

What happens in Anophase during Mitosis?

Answer 13

Sister chromatids are pulled apart to when spindles contract.

Question 14

What happens in Telophase during Mitosis?

Answer 14

Sister chromatids are pulled apart to opposite sides of the cell. The nuclear membrane reforms around each set of chromosomes, cytokinesis begins and two nuclei form.

Question 15

What is the purpose of mitosis?

Answer 15

For the repair, maintenance, growth, development and functioning of a living organism. Responsible for the creation of all somatic cells in the body.

Question 16

What happens in Interphase during Meiosis 1?

Answer 16

DNA replication and the cell enters the reproductive cycle with 4 copies of each chromosome.

Question 17

What happens in Prophase during Meiosis 1?

Answer 17

Chromosomes pair up in homologous pairs and crossing over occurs. The DNA condenses around histones—the nuclear membrane reforms.

Question 18

What happens in Metaphase during Meiosis 1?

Answer 18

Homologous chromosomes line up in the middle of the cell and random assortment occurs.

Question 19

What happens in Anophase during Meiosis 1?

Answer 19

Homologous chromosomes are pulled apart to opposite poles of the cell when the spindles contract.

Question 20

What happens in Telophase during Meiosis 1?

Answer 20

The nuclear membrane reforms and cytokinesis begins resulting in 2 haploid daughter cells.

Question 21

What happens in Prophase during Meiosis 2?

Answer 21

DNA condenses and chromosomes become more visible—the nuclear membrane disintegrates and the centrioles migrate.

Question 22

What happens in Metaphase during Meiosis 2?

Answer 22

Sister chromatids line up in the centre of the cell and spindles form.

Question 23

What happens in Anophase during Meiosis 2?

Answer 23

Sister chromatids are pulled apart to opposite poles of the cell and spindles contract.

Question 24

What happens in Telophase during Meiosis 2?

Answer 24

The nuclear membrane reforms around the sister chromatids. Cytokinesis begins resulting in 4 non-identical haploid daughter cells, each genetically different.

Question 25

Is DNA double/single-stranded?

Answer 25

Double-stranded.

Question 26

What bases are present in DNA?

Answer 26

Adenine, Thymine, Cytosine, and Guanine.

Question 27

What type of sugar is on the Backbone?

Answer 27

Deoxyribose

Question 28

What is the function of DNA?

Answer 28

Controls cell growth and development.