Eukaryotic Cell Cycle - Mitosis and Cytokinesis in animal and plant cells

Question 1

Interphase and chromatin and chromosome

Answer 1

The first stage of the
eukaryotic cell cycle which involves cellular growth and duplication of
chromosomes.

Composed of three
phases: G1, S, and G2

Chromatin:
chromosomes
(DNA and proteins) that have
been unwound and loosely packed
during interphase

chromosome a structure
composed of DNA tightly wrapped
around histone proteins. Carries the genetic information (genes)
of a cell

Question 2

Three sub-phases and the resting phase

Answer 2

1. G1
2. G0
3. S
4. G2

Question 3

G1 phase

Answer 3

In the G1 phase, the cell grows by:
- increasing the volume of its cytosol
- synthesising proteins for DNA replication
- replicating its organelles.

Question 4

G0 (resting phase)

Answer 4

Cells that are not required to replicate rest in the G0 phase.

Cells in G0 are either
quiescent or terminally differentiated.

Question 5

Synthesis (S) phase

Answer 5

The cell replicates its DNA turning one chromosome into two genetically identical sister chromatids

After the S phase, each somatic cell
will still contain 46 chromosomes.

Question 6

G2 Phase

Answer 6

The G2 phase is the final stage of interphase where the cell continues to grow and prepare
itself for mitosis. The G2 phase is similar to the G1 phase in that it involves:
- increasing the volume of the cytosol
- synthesising proteins in preparation for mitosis.

Question 7

Quiescent dormant cells

Answer 7

Dormant cells which can re-enter the cell cycle

Question 8

Terminally differentiated

Answer 8

Cells
that have fully specialised and no
longer replicate

Question 9

Chromatid

Answer 9

One half of a double stranded
chromosome

Question 10

Centromere

Answer 10

Holds sister chromatids together

Question 11

Mitosis

Answer 11

The second stage of
the eukaryotic cell cycle, which
involves the complete separation
of sister chromatids and nuclei

Question 12

Prophase

Answer 12

• Spindle fibres appear
• Chromosomes condense
• Breakdown of nuclear membrane

Question 13

Spindle fibres

Answer 13

Move chromosomes to either pole of the cell during mitosis and meiosis

Question 14

Metaphase

Answer 14

• Spindle fibres attach to chromosomes
• Chromosomes align along the equator

Question 15

Anaphase

Answer 15

• Centromere divides
• Sister chromatids move to opposite poles
• Spindle fibres contract

Question 16

Telophase

Answer 16

• Nuclear membrane reforms
• Chromosomes condense
• Spindle fibres disappear

Question 17

Somatic cells

Answer 17

Cell that is
not a reproductive cell (such as sperm and egg cells)

Question 18

Somatic cells

Answer 18

Contain two sets of chromosomes
– one inherited from each parent

Question 19

Centrioles

Answer 19

Cylindrical structures
composed of protein which form the spindle fibres during mitosis
and meiosis