16.2 Reproduction of Somatic Cells

Question 1

What are the 3 important functions of Mitosis and Cytokinesis?

Answer 1

Growth
Maintenance
Repair

Question 2

Why is growth an important function?

Answer 2

They enable organisms to grow from a single-celled zygote into a mature organism that may contain hundreds of trillions of cells

Question 3

Why is Maintenance an important function?

Answer 3

They produce new cells to replace worn out or dead cells

Question 4

Why is Repair an important function?

Answer 4

They can regenerate damaged tissues

Question 5

What must be done to ensure that the 3 important functions are able to take place?

Answer 5

The genetic material of the parent cell must be replicated
The replicated chromatin must be condensed and organized as chromosomes in the nucleus
One complete set of chromosomes must be divided into each of two new nuclei
The cell cytoplasm must divide to produce two complete and functional daughter cells

Question 6

What Phase of the interphase does DNA replication take place?

Answer 6

During the S Phase

Question 7

What does the cell do during the G2 phase of cell division?

Answer 7

The cell begins manufacturing or assembling other materials it will require for mitosis or cytokinesis

Question 8

What happens at the end of the interphase?

Answer 8

The chromatin consists of two identical sets of DNA and the cell is ready to begin mitosis

Question 9

What are the 4 Phases of Mitosis?

Answer 9

Prophase
Metaphase
Anaphase
Telophase

Question 10

What is the Prophase?

Answer 10

The first of the 4 phases in Mitosis

Question 11

What happens during the Prophase?

Answer 11

The chromatin condenses into tightly packed chromosomes and nuclear membrane breaks down releasing the chromosomes into the cytoplasm

Question 12

What do the Centrioles do during the Prophase?

Answer 12

They move part to opposite sides of the cell

Question 13

What happens as the centrioles move apart during the Prophase?

Answer 13

A network of fibers called the Spindle Apparatus forms between the centrioles

Question 14

What is each Spindle Fiber made of?

Answer 14

Microtubules

Question 15

What are microtubules?

Answer 15

Hollow tubes of protein that facilitate movement of chromosomes within the cell

Question 16

What is the second phase of Mitosis?

Answer 16

The Metaphase

Question 17

What happens during the Metaphase?

Answer 17

The Spindle Fibers guide the chromosomes to the centerline of the cells and have them facing opposite ways

Question 18

What do the Spindle Fibers attach to?

Answer 18

The centromere of each chromosome

Question 19

What is the third phase of Mitosis called?

Answer 19

The Anaphase

Question 20

What happens during the Anaphase?

Answer 20

Each centromere splits apart and the sister chromatids separate from each other and the spindle fibers that link the centromeres to the pole shorten and pull the chromatids to opposite poles

Question 21

What is the result at the end of the Anaphase?

Answer 21

One complete diploid set of chromosomes has been gathered at each pole of the elongated cell

Question 22

What is the Fourth Phase of Mitosis?

Answer 22

The Telophase

Question 23

What begins the Telophase?

Answer 23

The chromatids reaching the opposite polls of the cell

Question 24

What happens during the telophase?

Answer 24

The Chromatids unwind into the longer less visible strands of chromatin and the spindle fibers breakdown. A nuclear membrane forms around each new set of chromosomes and a nucleolus forms within each new nucleus

Question 25

What follows the process of Mitosis?

Answer 25

Cytokinesis

Question 26

What is cytokinesis?

Answer 26

The division of the cytoplasm to complete the creation of two new daughter cells

Question 27

What happens during Cytokinesis in Animal Cells?

Answer 27

An indentation forms in the cell membrane along the equator which depends until the cell is pinched in two. The cytoplasm and the organelles divide equally between two halves of the cell

Question 28

What is different in Mitosis in Plant and Animal cells?

Answer 28

Plant cells do not have centrioles but form the spindle apparatus
Instead of cell wall pinching during cytokinesis a membrane called the cell plate forms between the two daughter nuclei