Apoptosis and necrosis

Question 1

Define ischaemia

what are the main causes

Answer 1

Ischaemia = lack of blood flow to organ/tissue

Causes:

atheroma= fatty deposit

thrombus = blood clot

embolism = when a piece of thrombus/atheroma or air travels through bloodstream and cases a blockage in a smaller vessel downstream

Question 2

Formation of thrombus

Answer 2

Caused by an increased amount of prothrombotics in blood

thrombus occurs when a clot forms at the site of stenosis (narrowing of vessel)

Question 3

Causes of cell injury (5)

Answer 3

• Energy failure
  
  • lack of oxygen/glucose - from ischaemia or conditions that reduce blood flow
  • mito failure
• blockage of metabolic pathways
  
  • enzyme inhibiton
  • interruption of protein synthesis
  • respiratory posions
  • lack of growth hormone / other hormones
• physical trauma/osmotic pressure
• DNA damage
  
  • radiation
  • chemotherapy
  • free radicals
• Damage to membrane
  
  • damage to ion pumps
  • cold temperatures
  • bacterial toxins
  • perforin(glycoprotein that forms pores in membranes ) damage
  • Complement proteins (form part of immune response )

Question 4

Events occurring in a sublethal injury

Answer 4

Question 5

Cellular morphology during necrosis

Answer 5

Question 6

Infarction meaning

Answer 6

Tissue death due to necrosis that is caused by ischaemia

Question 7

Define apoptosis

what are the main causes ?

Answer 7

Programmed cell death

active and regulated

due to DNA damage or lack of growth hormone or osmotic pressure

Question 8

Cellular morphology during apoptosis

Answer 8

Question 9

pathological and physiological uses of apoptosis

Answer 9

Question 10

Disregulation of apoptosis

Answer 10