Levels of Organisation and Cell Structure

Question 1

What is a specialised cell?

Answer 1

A cell within an organism which has adapted to perform a specific function through developing a different strucure and composition of subcellular structures (differentiation)

• Each cell in an organism will have the same genetic information, but only some of it will be used
• Examples include a sperm cell or a root hair cell

Question 2

What are undifferentiated cells called?

Answer 2

Stem cells

Question 3

When does most differentiation happen in animals?

Answer 3

When they are an embyro, although adult stem cells do exist in places such as the bone marrow

Question 4

When does differentiation happen in plants and where do the stem cells come from?

Answer 4

Throughout their whole life via meristem tissue

Question 5

How can stem cells be used in medicine?

Answer 5

• To grow new tissue and repair broken organs
• It can treat autoimmune diseases like diabetes

Question 6

Why must an embryo grown through therapeutic cloning be used?

Answer 6

So that the stem cells are not rejected by the patients body

Question 7

What are the benefits of using stem cells in medicine?

Answer 7

• Can treat a variety of diseases like diabetes
• Embyros grown through therapeutic cloning will produce stem cells which will not be rejected, like it does for organs which are donated.

Question 8

What are the medical risks associated with stem cell treatment?

Answer 8

• A virus could be transmitted from the stem cell cultured in the lab to the patient
• The cultured stem cell could develop mutations and become cancerous

Question 9

What are the ethical issues with stem cell treatment?

Answer 9

• There is no saying who owns the embyro and who has rights over it
• Is it right to clone (playing god)?
• Should an embryo be treated as a person or not?