cell divison

What type of cells undergo mitosis

Non reproductive cells (somatic cells)

What cells undergo meiosis

Reproductive cells (testicles and overlies )

Key differences between mitosis and meiosis

Mitosis

• parent cell becomes 2 daughter cels

• Daughter cells are identical

• Daughter cells has same number of chromosomes as parent cell

Meosis

• parent cell becomes 4 daughter cells (gamates)

• Daughter cels have half the genetic composition of the parent cells

What is the purpose of mitosis

Growth- creates cells needed to maintain growth

Tissue repair- replaces damaged cells

What does a flatworm regenerate

Any body part

What does a starfish regenerate

Limbs and whole body if central nerve ring is attached

What does an axolotil regenerate

Limbs and spine

What does a frog regenerate

Tadpoles regenerate limbs but loose the ability in adulthood

What is the purpose of meiosis

Reproduction- create new life

Describe the process of fertilisation after meiois s

• Sperm and egg (half DNA) cell come togetehr in fertilisation to create a zygote (full DNA)

Why does mitosis happen after meiosis in some reproductive cells

Zygotes undergo mitosis to create more cells are grow

Mitosis phases

• prophase

• Prometaphase

• Metaphase

• Anaphase

• Telophase

• Cytokinmseses

Meiosis process

• interphase

• Prophase i

• Prometaphase i

• Metaphase i

• Anaphase i

• Telophase i

• Cytoplasm kinases

Same again in meiosis ii

• prophase ii ….. so on

What happens in the interphase of the cell cycle

G1- before DNA synthesis, preps are for cel division, increase in size

Sphase- DNA is synthesised, DNA content doubles

G2 phase- DNA synthesis has occurred, cells synthesise aditional proteins and keep incerasising in size

What happens in the Mitotic phase of the cell cycle

Contents of dividing cells are equally distrabuted between 2 daughter cells

What happens during the G0 phase

Non dividing phase

Cells remain in this state until they are signalled to process thorough the cell cycle

How often does cell division occur?

Blood cells in bone marrow, skin cells, cells lining stomach and intestine- divide rapidly

Kidney, liver and lung cells- divide when sneezed due to damaged or dead cells

How is cancer caused in terms on the cell cycle

P53 is the gardian genome

It checks our error in dna the stops cell reproduction.

If there is an erre in the p53 cell tumours can grow

What cells don’t undergo mitosis

Rend blood cells as they have no nucleus

Skeletal muscle cell as sat alone stem called replace damage

Cardiac muscle

Nerve cells

What is a stem cell

Undifferentiated cells (immature cells)

Capable of self renewal

Capable of differentiation

What happens to stem cells in cell division

1 daughter cell becomes specialised the other stays as a stem cell

What is an embryonic stem cell

Capable of self renewal

can differentiate into many types of cells

What is a somatic stem cells

Capable of self renewal

Can only differentiate to a limited number of cells

What are the applications of stem cells

Tissue engeneering

Used in treatments/ research like :

• heart tissue regeneration

• Alzheimer’s treatment

• Leukemia treatment

• Kidney disorder