CELL CYCLE NOTES:

1. What is the Cell Cycle? The Cell Cycle is the Life Cycle of a cell.

2.) What is Mitosis?

- Cell Division for Somatic (Body) Cells.

3.) What is Meiosis?

 

- Cell Division for Sex Cells (Gametes)

4) What is a Chromosome? - Chromosomes are made up of DNA & Protein.
- Contained in Nucleus in Eukaryotic Cells
- Main ring of DNA in Prokaryotic Cells.
5.) What is a Chromatid? - 1/2 a Chromosome.
6.) What are Chromatin? - Unwound Chromosomes.
7.) How is the Cell Cycle Divided? - The Cell Cycle is divided into 3 Stages.
- Stage 1 = Interphase (G1, S, G2)
- Stage 2 = Mitosis (Prophase, Metaphase, Anaphase & Telophase)
- Stage 3 = Cytokinesis
8.) What are the 4 Phases of Mitosis? - Prophase, Metaphase, Anaphase, & Telophase (PMAT)
9.) What are the 8 Phases of Meiosis? - Prophase1, Metaphase1, Anaphase1, Telophase1,
- Prophase2, Metaphase2, Anaphase2 & Telophase2
10.) 1st Stage = Interphase (G1, S, G2)

- Cell grows to its mature size & copies its organelles & chromatin.
(DNA & Protein)

11.) 2nd Stage = Mitosis - Cell prepares to divide. (Prophase, Metaphase, Anaphase & Telophase)
12.) Mitosis Phase 1 = Prophase - Chromosomes condense from long strands (chromatin) to rodlike structures
(chromosomes). Centrioles & spindle fibers appear. The nuclear
membrane begins to disappear.
13.) Mitosis Phase 2 = Metaphase - The Nuclear Membrane is dissolved.
- Paired Chromosomes align at the cell's equator. (Middle of the cell.)
- Centrioles move to opposite poles & attach spindle fibers to the chromosomes.
14.) Mitosis
Phase 3 = Anaphase
-The spindle fibers pull on the chromosomes,
which causes the chromatids to separate.
- The chromatids are pulled apart towards
opposite ends of the cell.
15.) Mitosis Phase 4 = Anaphase - The cell membrane pinches inwards.
- A Nuclear Membrane reforms
around each set of chromosomes,
at opposite ends of the cell.
Chromosomes become chromatin.
17.) How many chromosomes are
contained in Human Diploid Cells &
Human Haploid Cells?
- Human Diploid Cells contain 46 Chromosomes (A full set of chromosomes).
- Human Haploid Cells contain 23 Chromosomes (Half a set of chromosomes).
18.) What is Binary Fission? - A type of asexual reproduction amongst prokaryotes (simplest organisms)
where the cell copies the circular chromosome (ring of DNA) & then divides
into 2 new cells.
19.) Which organisms reproduce by
Binary Fission?
- Bacteria use Binary Fission to reproduce.

CELL CYCLE DIAGRAMS:

1st Stage = Interphase (G1, S, G2) Interphase
2nd Stage = Mitosis Prophase, Metaphase, Anaphase & Telophase
Mitosis Phase 1 = Prophase Prophase
Mitosis Phase 2 = Metaphase Metaphase
Mitosis Phase 3 = Anaphase Anaphase
Mitosis Phase 4 = Telophase Telophase

6.) 3rd Stage = Cytokinesis

 

 

*** Overall Cell Cycle =

- 1st Stage = Interphase (Divided into G1, S & G2 Phases)

- 2nd Stage = Mitosis (Divided into Prophase, Metaphase, Anaphase & Telophase)

- 3rd Stage = Cytokinesis (Final Division of Cell)