Question

Difference between extrinsic and intrinsic pathway of apoptosis

Answer 1

Answer:

Apoptosis can be defined as the programmed cell death that takes place in the body of an organism.

The intrinsic pathway of the apoptosis is initiated in response to the internal stimuli. It can be due to biochemical stress, Lack of growth factors, DNA damage.

These are some of the cases when the intrinsic pathway of apoptosis takes place.

The extrinsic pathway of apoptosis an be defined as the cell death which is induced due to external stimuli. It takes place by the binding of ligand at death receptors found on the cell surface.

Answer 2

Difference between ‘Extrinsic and Intrinsic’ pathway of apoptosis are given below:

Extrinsic pathway:

• Initiation involve ‘transmembrane receptor’-mediated interactions.

• Involve death receptors.

• No mitochondrial initiated events are involved.

• No apoptosome formation.

• Caspase 8 is activated.

• Signals in this pathway usually act in a positive fashion.

Intrinsic pathway:

• Initiation involve a diverse array of ‘non-receptor-mediated’ stimuli that produce ‘intracellular signals’.

• No death receptors are involved.

• ‘Signals’ act directly on targets within the cell and initiate mitochondrial-initiated events.

• Apoptosome formation takes place.

• Caspase 9 is activated.

• Signals in this pathway may act is a ‘positive or negative’ fashion.