Cell Divison

Question 1

What is mitosis and meiosis

Answer 1

Asexual reproduction. Cell division producing two diploid cells with identical set of chromosomes as the parent

Sexual reproduction of cell division producing four haploid cells with different set of genes from each other and from the parent

Question 2

Stages of mitosis

Answer 2

Prophase metaphase anaphase telophase

Question 3

Prophase

Answer 3

Chromosome condense and attach

Chromatids become joined at centromere by kinetochore

centrosomes move to opposite poles

nuclear envelope nucleolus and lamina phosphorylated and disappear by fragmentation causing pores to disperse in cytoplasmic membrane physicals

Question 4

Metaphase

Answer 4

Chromosomes condense further

centromere attaches to spindle chromosomes align it equatorial plate

Question 5

What is mitotic spindle

Answer 5

These are microtubules made of Kinetochore proteins which attach to centromere‘s of chromosomes also has astral tubules which connect to membrane

Question 6

Anaphase and how spindle separates chromatids

Answer 6

• chromosomes split and move to oppsite poles
• chromatids are separated and moved towards opposite poles spindle pulls on centromere via myosin proteins into change length of microtubules

Question 7

Telophase and cytokinesis description

Answer 7

• cytokines by actin and myosin splitting cell into 2
• Chromosomes at opposite poles decondense

spindle depolymerizes

nuclear envelope develops around each pair of chromosomes

Nucleoli , lamina and pores reappear

contractile actin ring develops in cortical cytoplasma and cytokinesis occurs ( constriction of ring in cleavage furrow until cell divides into two )

Question 8

Stages of meiosis

Answer 8

Late interphase- synapses and crossing over begins chromosomes condense
Meiosis 1
Prophase 1 - Crossing over continues chromosomes attached at Centromere

Metaphase 1 - Homologous lines fill up double file

Anaphase and telophase 1 - Cell splits into two haploid sister chromatids still attached

Meiosis 2
Metaphase 2 - Chromosomes line up double file in in the two haploid cells along the equatorial plate

Anaphase and telophase 2 - sister chromatids now separated and the two haploid cells divide into four haploid cells

Question 9

Diff of meiosis and mitosis

Answer 9

• Meiosis is sexual reproduction producing cells with different genetic material
• Meiosis produces for haploid cells whilst mitosis produces to diploid cells

Question 10

Similarity of meiosis and mitosis

Answer 10

Condensation chromatids separation and alignment along the equatorial plate