Totipotency And Cell Specialisation

Question 1

What can totipotent stem cells do?

Answer 1

Mature into any type of cell

Question 2

Example of how RBC specialised?

Answer 2

Loses nucleus so more room for O2
Biconcave for bigger SA
Haemoglobin for red colour and pick up O2
Flexible to fit through capillaries

Question 3

Why are only some genes expressed?

What two ways is this done?(2)

Answer 3

DNA prevented from being translated
mRNA broken down before translated
siRNA prevent transcription in first place

Question 4

What can not be done once a cell is specialised?
What does it lose?
What is an embryonic stem cell?
Why is this?
What does it mean for a cell to be multi potent?

Answer 4

Reversed 
Totipotency 
Pluripotent 
Can give rise to other stem cells 
An adult stem cell, so undifferentiated but diving

Question 5

Examples of where undifferentiated cells are found?

Why can these be used to treat disorders?

Answer 5

Inner lining of small intestine
Bone marrow
Brain
Adipose tissue

Can develop into other cells in certain conditions

Question 6

What do mature plants have?
How can you clone a plant?
What’s this called?

Answer 6

Multi potent cells
Take cells, put in nutrient medium, add chemical stimuli at right time
Vitro fertilisation

Question 7

All cells of an organism have the same genes but some are?
What are some genes? Eg?
And other genes are?

Answer 7

Not expressed
Switched on in all cells, enzymes
Permanently switched off