B2 - Cell division

Question 1

How many chromosomes are there

Answer 1

Somatic(body) cells have two pairs of 23 chromosomes (46 in total)
Gametes contain 23 chromosomes

Question 2

Why is the cell cycle important?

Answer 2

The cell cycle involves mitosis, producing identical cells for growth, repair and development of multicellular organisms.

Question 3

Describe the cell cycle

Answer 3

 Stage 1: longest stage, cells get bigger, DNA is replicated, two copies of each chromosome formed, more sub-cellular structures produced.
 Stage 2: (mitosis) each chromosome replicated to have two identical chromosomes , chromosomes align in middle, chromosomes pulled apart to either end of the cell, and then the nucleus divides.
 Stage 3: cytoplasm and cell membrane divide; cell divides to form two daughter cells.

Question 4

Importance of Differentiation

Answer 4

Differentiation creates different cells for specific organs and specific roles. This happens as cells divide, grow and develop.