Chapter 9 Genetics And Cell Division

Question 0

What are the four stages of mitosis?

Answer 0

1) Prophase
2) Metaphase
3) Anaphase
4) Telophase

Question 1

Mitosis

Answer 1

-The separation of a somatic cell’s duplicated chromosomes prior to cytokinesis

Question 2

Chromatin

Answer 2

• A molecular complex of DNA and its associated proteins that make up the chromosomes of eukaryotic organisms
• Interphase chromosomes = chromatin; loosely scattered arrangement of chromosomes

Question 3

Chromosome

Answer 3

• A structural unit containing part or all of an organism’s genome, consisting of DNA and its associated proteins (chromatin)
• The human genome is made up of 23 pairs of chromosomes or 46 chromosomes in all

Question 4

Sister chromatids

Answer 4

Two identical strands of chromatin that make up a chromosome in the duplicated state

Question 5

Centromere

Answer 5

The region joining the two sister chromatids that make up an x-shaped chromosome

Question 6

DNA replication

Answer 6

• The process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules
• Replication is an essential process because whenever a cell divides, the two new daughter cells must contain the same genetic information, or DNA, as the parent cell

Question 7

Homologous chromosomes

Answer 7

A set of one maternal chromosome and one paternal chromosome that pair up with each other inside a cell during mitosis
-These copies have the same genes in the same locations

Question 8

Cell cycle

Answer 8

The series of events that take place in a cell leading to its division and duplication (replication) that produces two daughter cells

Question 9

Interphase

Answer 9

The portion of the cell cycle in which the cell simultaneously carried out its work and in preparation for division, duplicates its chromosomes

Question 10

Prophase

Answer 10

• The first stage of cell division, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears
• The first prophase of meiosis includes the reduction division

Question 11

Metaphase

Answer 11

The second stage of cell division during which the chromosomes become attached to the spindle fibers and align them at the metaphase plate

Question 12

Anaphase

Answer 12

• The stage of meiosis or mitotic cell division in which the chromosomes move away from one another to opposite poles of the spindle
• Each chromatid becomes a full chromosome

Question 13

Telophase

Answer 13

-The final phase of cell division in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed

Question 14

Karyotype

Answer 14

A pictorial arrangement of a full set of an organisms chromosomes

Question 15

Mitotic phase (M phase)

Answer 15

-The portion of the cell cycle that includes both mitosis and cytokinesis

Question 16

Centosome

Answer 16

• A cellular structure that acts as an organizing center for the assembly of microtubules
• A cell’s centrosome duplicates prior to mitosis and plays an important part in the development of the cell’s mitotic spindle

Question 17

Mitotic spindle

Answer 17

The microtubules active in cell division, including those that align and move chromosomes

Question 18

Metaphase plate

Answer 18

A plane located midway between the poles of a dividing cell

Question 19

Cell plate

Answer 19

• in plant cells
• A plate that develops at the midpoint between the two groups of chromosomes in a dividing cell and that is involved in forming the wall between the two new daughter cells

Question 20

Genome

Answer 20

The complete collection of an organisms genetic information

Question 21

Microtubules

Answer 21

The largest of the cytoskeletal filaments
-microtubules take the form of hollow tubes composed of the rails on which transport vesicles move, and form the cellular extensions known as cilia and flagella

Question 22

Describe the structure of a replicates chromosome

Answer 22

• A replicated chromosome consists of two sister chromatids
• Each chromatid is one of the newly replicated DNA double helixes and its associated proteins
• DNA replication happens at the chromosomal level, consisting of a duplicated chromosome attached by the centromere in the middle

Question 23

What is the longest phase of the cell cycle? What three phases occur during this portion?

Answer 23

• Interphase is the longest portion of the cell cycle

- G1, S, and G2 occur during interphase

Question 24

Distinguish between the terms chromatin and chromosome

Answer 24

• Chromatin is composed of DNA and associated proteins, and makes up the chromosomes of eukaryotic organisms
• Chromosomes contain part or all of an organisms genome consisting of chromatin

Question 25

G1 phase

Answer 25

• The fist phase in interphase (gap-one)

- The cell is growing and carrying out its normal functions

Question 26

S phase

Answer 26

• The second phase in interphase (synthesis phase)

- The cell is replicating its DNA (duplicating its chromosomes) in preparation for mitosis and cytokinesis

Question 27

G2 phase

Answer 27

• The third phase in interphase (gap-two)
• DNA replication has been completed, and the cell continues with its normal functions, even as it prepared for mitosis and cytokinesis

Question 28

Cytokinesis

Answer 28

the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.