biology: stem cell ·˚ ༘

Differentiation definition

The journey a cell takes from being a less specialised cell (or early cell) to a mature cell type.

Specialisation

This refers to the cells final adapted form and function, such as a muscle cell for contraction or a red blood cell for oxygen transport.

Label the parts of this diagram and say what is showing

This diagram is showing the two functional capabilities a stem cell does, self renewal and differentiation

Label this diagram showing and say what it is showing

It is showing how an embryonic stem cell becomes an adult stem cell

Pluripotent definition

A stem cell whicb can divide and change into almost any cell type in the body e.g. embryonic stem cell

Explain the process of different action and label this diagram

Differentiation is the process a pluripotent stem cell (which is an unspecialised cell e.g. an embryonic cell)goes through to become a specialised cell with a specific function e.g. nerve cell

Blastocyst definition

A very early embryo

What is an embryonic cell and where do they come from

Embryonic stem cells are pluripotent unspecialised cells which are taken from a 3 to 5 day old preimplantation embryo called a blastocyst.

What are adult stem cells

Adult stem cells are undifferentiated cells found in children and adults whicb repair and maintain the specific organs where they live

What happens in a stem cell transplant

In a stem cells transplant embryonic cells are first specialised into adult cell types. Then those mature cells replace tissue that is damaged by disease or injury.

What can a stem cell transplant be used to do

• replace neurons damaged by spinal cord injury. Parkinson’s disease or other neurological problems.

• Produce insulin that could treat people with diabetes and heart muscle cells that could repair damage after a heart attack.

• Replace virtually any tissue or organ that is injured or diseased

How many groups of stem cells are their in animals

There are 3 groups of stem cells

• adult stem cell

• Embryonic stem cell

• Therapeutically closed stem cells

What us the adult stem cells are

Produced in the bone marrow

What is the embryonic stem cell

Produced by embryos

What us the therapeutically cloned stem cell

They are embryonic stem cells which are specifically created for medical purposes.

Where the stem cells found in plants

Stem cells are found in the meristem tissue. Meristem tissue can be found in the:

• root tips

• Shoot tips

The root tips and shoot tips keep producing stem cells while they live.

What are the stem cells found issues

• clinical

• ethical

• Social

Clinical issues to do with stem cell transplant

• difficult to find suitable stem cell donors

there is no guarantee of how successful these therapies will be e.g. doctors do not yet have a foolproof way of making sure that Parkinson’s disease does not destroy neurons as they need them to survive in order for stem cell transplant to work.

• it is difficult to maintain and store a patients embryonic stem cell

Ethical issues to do with stem cell transplant

• at what stage of its development should an embryo be regarded as and treated as a person ?

• For therapeutic cloning is it right to create embryos for therapy and destroy them in the process ?

• Embryos could come to be viewed as a commodity and not an embryo that could develop into a person.

Social issues to do with stem cell transplant

• most of the research is carried out by a commercial clinic so reported success not subject to peer review.

• Patients could be exploited as they are paying for expensive treatments and being given false hope of a cure when stem cell transplant are only in their developmental stages.

• educating the public about what stem cells can and can’t do is important to spread awareness.

Therapeutic stem cells

Therapeutic stem cells are made through a process called therapeutic cloning.

• it is called therapeutic because it is used for therapy.

• In therapeutic stem cells donors only donate an egg cell

  
  

Stem cell

Stem cell is an unspecialised cell capable of differentiating into a specialised cell.

Clone

Means genetically identical cell