B2- The Cell Cycle Flashcards
What is the cell cycle?
The cell cycle is a series of stage that allows a cell to make a copy of itself
How much chromosomes does a normal body cell have?
46 chromosomes
How much chromosomes does a sex cell have
23 chromosomes for the sperm
23 chromosomes for the egg cell
Why do cells need to divide?
To replace damage cells / worn out cells
For growth
To repair body tissues (e.g. muscle/bone)
To produce sex cells(sperm & egg)
What are the two types of cell division
Mitosis & Meiosis
What is mitosis?
It the division of normal body cells
What is meiosis
Its the division of sex cells/gamelets
How much stage in mitosis are there?
3 stages: Interphase, Mitosis and cytokinesis
Explain interphase
The cell spends most of its life during this phase
There are 3 stages of cellular interphase: g1 (gap1), S (synthesis) and g2 (gap2)
During gap 1 the cell produces high amounts of protein synthesis and more organelles are made ( the cell also doubles in size)
During synthesis the cell duplicates its DNA
During gap 2 the cell resumes its growth until mitosis begins
Explain stage 2 MITOSIS
During mitosis, the chromosomes, which have already duplicated, condense and attach to spindle fibres that pull a copy of each chromosome to the opposite side of the cell.
Explain stage 3 CYTOKINESIS
This is the process when a parent cell divides into 2 daughter cells.
This happens as the cytoplasm of the cell is cut in half and the organelles are split into forming 2 cells.
What do we call the disease when cells divide and multiply for no reason uncontrollably?
Cancer
What would happen if a sperm with 24 chromosomes met up with a egg cell with 23 chromosomes?
The child would then be disabled.
