Cell Division, Differentiation Flashcards Preview

OCR A-level Biology > Cell Division, Differentiation > Flashcards

Flashcards in Cell Division, Differentiation Deck (14)
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1

What are the 2 main stages of the cell cycle

Interphase
Mitosis

2

What are the 3 cell cycle checkpoints

G1
S
G2

3

Why are there cell cycle checkpoints

Prevent uncontrolled division (Cancer)

Detect damage to DNA and cells

4

What is the name of the process where a faulty cell is detected and destroyed

Apoptosis

5

Where are the 2 main checkpoints found

between: G1/S and G2/M

6

What happens in the S phase of the Cell cycle

DNA synthesis

7

What is the function of cell division

Growth: organisms grow by producing more cells that are genetically identical to each other

Repair: Wound and tissue damage are healed by tissues producing more cells to replace damaged ones

8

What is meant by Asexual Reproduction

Where single celled organisms (like amoeba) divide by mitosis to form new individuals

9

What are the 4 stages of Mitosis

Prophase
Metaphase
Anaphase
Telophase

10

What happens during prophase

Chromosomes condense (become visible under microscope)

Breakdown of nuclear envelope

Centriole divides and daughter centrioles move to poles of cell

Spindle fibres start to form (make of tubulin from cytoskeleton)

11

What happens during metaphase

Chromatid pairs line up down the equator

Join onto the spindle fibres by their centromeres

12

What happens during anaphase

The centromere splits

Motor proteins pull the chromatids in opposite directions towards the poles

13

What happens during telophase

The chromosomes reach the poles

A new nuclear envelope forms round each new group of chromosomes

14

What is the name of the process where the cell membrane divides into 2

Cytokinesis