Cell differentiation

Plants and animals have stem cells.

These are cells that have not undergone changes to become specialised cells.

Which process do stem cells go through to become specialised cells?

Tick (✓) one box.

The table gives features of different types of stem cells.

Complete the table by putting one tick (✓) in each row.

One type of specialised cell in a plant is a root hair cell, shown in the diagram.

Give a function of a root hair cell and state how it is adapted for that function.

One role of a root hair cell is to move ions into the plant against the concentration gradient.

State the name given to this type of transport.

Which process do cells go through when they specialise?

A Differentiation

B Meiosis

C Mitosis

D Osmosis

Adult stem cells found in skin usually only form new skin cells.

• Scientists have developed adult skin cells that can be reprogrammed into ‘embryonic – like’ stem cells.

• These stem cells are called iPS cells and they can be used as a source of any human cell.

Which process turns stem cells into specialised skin cells?

Both embryonic stem cells and iPS cells are used in medical research.

The graph shows the number of scientific papers published by scientists who have used either embryonic stem cells or iPS cells in their research.

Give one reason why it is important for scientists to publish their research.

How many more scientific papers used iPS cells rather than embryonic stem cells in 2016?

Suggest two reasons for the difference in use between the two types of stem cells seen in 2016.

The diagram shows a cell during one stage of mitosis.

Describe two things that happen to the chromosomes in the next stage of mitosis.

Chromosomes are made of DNA.

Describe the structure of DNA.

After mitosis, cell differentiation takes place.

What is meant by the term cell differentiation ?

The diagram shows a cell during one stage of mitosis.

Describe two things that happen to the chromosomes in the next stage of mitosis.

Chromosomes are made of DNA.

Describe the structure of DNA.

After mitosis, cell differentiation takes place.

What is meant by the term cell differentiation ?

Type 1 diabetes is a disorder caused by lack of insulin production in the pancreas. Type 1 diabetes has a genetic link.

In humans the haploid number of chromosomes is 23. Insulin is a hormone controlled by a single gene found on chromosome number 11.

How many chromosomes are there in a single human pancreas cell?

Some individuals have a copy of the gene that would cause diabetes but do not have the disorder.

Suggest a reason why.

Some people can inherit a rare condition called ADPKD that results in kidney disease.

The PKD1 gene provides instructions for making a protein called polycystin-1. Polycystin-1 controls kidney cell differentiation.

In ADPKD, polycystin-1 does not work properly.

What name is given to a change in the PKD1 gene that causes ADPKD?

Explain why the ADPKD version of polycystin-1 prevents the kidney working properly.

A pregnant woman is heterozygous for ADPKD. The baby’s father does not have ADPKD and is homozygous recessive.

ADPKD is caused by a dominant allele (D).

What is the probability of their baby having ADPKD?

Use a labelled genetic diagram to explain your answer.