Mitosis Flashcards Preview

Chapter 6 Cell Division > Mitosis > Flashcards

Flashcards in Mitosis Deck (14):
1

What is mitosis?

-Process of cell division in eukaryotic cells, but mainly nuclear division.
-Ensures both daughter cells produced when parent cell divides are genetically identical.

2

What is mitosis necessary for?

-When all daughter cells have to be identical so for, growth and repair of tissues.
-Also, for asexual reproduction.

3

What is asexual reproduction?

-Production of genetically identical offspring from one parent in organisms like plants and fungi.

4

What is a chromosome?

-DNA molecule.

5

What is a chromatid?

-Two identical DNA molecules.

6

What happens to chromosomes during interphase?

-Each chromosome is converted into chromatids.

7

What is the centromere?

-Region where two chromatids are joined together.

8

What are the four stages of mitosis?

-Prophase, metaphase, anaphase and telophase.

9

What happens during prophase?

-Chromatin fibres begin to coil and condense to form chromosomes. The nucleolus disappears and nuclear membrane breaks down.
-Protein microtubules form spindle shaped structures linking the poles of the cell. Fibres are necessary to move chromosomes.
-Two centrioles migrate to opposite poles.
-Spindle fibres attach to centromeres and move chromosomes to centre of cell.
-By the end, nuclear envelope had disappeared.

10

What happens during metaphase?

-Chromosomes moved by spindle fibres to form a plane in the centre called the metaphase plate and held in position.

11

What happens during anaphase?

-Centromeres holding the pair of chromatids in each chromosome divide.
-Sister chromatids separated and pulled to opposite poles.
-4 "V" shaped chromatids at each pole.

12

What happens during telophase?

-Chromatids have reached poles and now called chromosomes.
-Two new sets of chromosomes assemble at each pole and nuclear envelope reforms.
-Chromosomes uncoil and nucleolus forms.
-Cytokinesis begins.

13

How is cytokinesis performed in animal cells?

-Cleavage furrow forms around middle of cell.
-Cell-surface membrane pulled inwards by cytoskeleton until close enough to fuse.
-Forms two identical daughter cells.

14

How is cytokinesis performed in plant cells?

-Vesicles from Golgi assemble in same place as metaphase plate was.
-Vesicles fuse with each other and cell-surface membrane divides cell into two.
-New cell walls then forms along new section of membrane.