Cell Division

Question 1

Increase in cell number because of the process called cell division.

Answer 1

Cell Cycle

Question 2

What is the Interphase?

Answer 2

Phase of the cell cycle in which a typical cell spends most of its life. During this phase, the cell copies its DNA in preparation for Mitosis.

Question 3

Draw the parts of a chromosome?

Answer 3

Centromere
Chromatid
Sister Chromatid
Telomere

Question 4

What are the parts in the Interphase?

Answer 4

Gap 1 (G1) - cells increase in size and RNA and proteins are produced.
Synthesis Phase (S) - DNA Replication. Chromosome replication. 23 pairs of chromosomes (46) with 2 chromatids each (92)
Gap 2 (G2) - Preperation for Cell Division. 23 pairs of chromosomes (46) with 2 chromatid each

Question 5

What are the 4 phase of the Cell Cycle?

Answer 5

• Gap 1
• Synthesis Phase
• Gap 2
• M Cycle

Question 6

What is Mitosis?

Answer 6

Division of the cells nucleus. Single cell divides into 2 identical daughter cells.

Question 7

What are the phases of Mitosis?

Answer 7

• Prophase: longest phase, when chromatin begins to condense into a shape of chromosomes. Nucleolus disappears. Nuclear Membrane disappears. Spindle fibers form from 2 centrioles and attach to the centromeres
• Metaphase: spindle fibers line up the chromosomes at the center of the cell.
• Anaphase: spindle fibers separate the sister chromatids at their centromere which move to opposite poles of the cell
• Telophase: a nuclear membrane forms in each set of chromosomes then spreads into chromatin and the nucleolus becomes visible again
• Cytokinesis: division of the cytoplasm

Question 8

What is Meiosis?

Answer 8

Cell division that produces gametes (sex cells)

Question 9

What happens in Meiosis I?

Answer 9

• Prophase I: starts with a diploid cell. Chromatin contains 2 sets of spread out chromosomes, one from each parent. condenses to chromosomes. Synapsis - chromosome pairs up with its corresponding homologous chromosome forming a tetrad (four chromatids) recombination/exchanges of alleles (genes). Nuclear Membrane disappears and spindles fibers form.
• Metaphase I: chromose line up at the center and attach to spindle fibers from opposite poles
• Anaphase I: spindle fibers seperate the homologous chromosomes and pull them apart.
• Telophase I: spindle fibers disappear. Nuclear membrane appears and cytokinesis occurs.

Question 10

What does Meiosis I end up?

Answer 10

2 genetically different Haploid Daughter Cells

Question 11

What happens in Meiosis II?

Answer 11

• Prophase II: nuclear membrane disappears. Spindle fibers form.
• Metaphase II: chromosomes line up at the center and attach to spindle fibers from both poles
• Anaphase II: sister chromatids separates and move to opposite poles. 1 chromatid is at the other side of the cell and the remaining one in the other.
• Telophase II: spindle fibers disappear. Nuclear membrane reforms and cytokinesis occurs

Question 12

What does Meiosis II end up?

Answer 12

4 genetically different Haploid Daughter cells