Pathology part 3

Question 1

Does necrosis require energy?

Answer 1

No

Question 2

Is necrosis pathological?

Answer 2

Always

Question 3

What is coagulative necrosis

Answer 3

Preservation of cell outline

Question 4

What are dead cells consumed by?

Answer 4

Various enzymatic processes and cells

Question 5

What is liquefactive necrosis?

Answer 5

Liquid viscous mass- no cell structure remains

Pus

Question 6

What is liquefactive necrosis associated with?

Answer 6

Localised bacterial and fungal infections in the brain

Question 7

What is caseous necrosis associated with?

Answer 7

Tuberculosis

ask for couture, PCR and look for result of ziegler neelson stain

Question 8

What is caseous necrosis?

Answer 8

granulomatous inflammation with central necrosis

Question 9

Define apoptosis

Answer 9

Programmed cell death in response to specific signals

Question 10

Does apoptosis require energy?

Answer 10

Yes

Question 11

Give an example of physiological apoptosis?

Answer 11

digit formation
removal of self reactive lymphocytes
hormonal-depandant involution

Question 12

What can pathological apoptosis occur as a result of?

Answer 12

Injury

• radiation
• chemotherapy
• viral infection- hepatitis
• cancers
• graft versus host disease

Question 13

What are the two pathways of apoptosis?

Answer 13

Extrinsic

Intrinsic

Question 14

Describe the extrinsic pathway of apoptosis

Answer 14

Death receptors initiated pathway

Cell membrane receptors with death domain

Question 15

What are the death receptors?

Answer 15

TNF and Fas

Question 16

What is the role of Fas?

Answer 16

Recognition of self

Apoptosis in lymphocytes

Question 17

What is the role of TNF?

Answer 17

Complex, induces apoptosis in association with inflammatory conditions

Question 18

What do people with Fas mutations often get?

Answer 18

Autoimmune diseases

Question 19

Describe the intrinsic pathway?

Answer 19

Mitochondrial pathway

Growth signals promote anti-apoptotic molecules in mitochondrial membrane

Question 20

What are anti-apoptotic molecules in membrane replaced by?

Answer 20

Bax, Bak

Question 21

What do Bax, Bak do?

Answer 21

Increase permeability of mitochondria

Release proteins that stimulate caspases

Cytochrome C

Question 22

What is p53 responsible for?

Answer 22

Sensing cell damage and halting cell cycle

If DNA can’t be repaired then p53 stimulates caspases and induces apoptosis

Question 23

What does too little apoptosis cause?

Answer 23

Cancer

Autoimmune disorders

Question 24

What does too much apoptosis cause?

Answer 24

Neurodegenerative disorders

Question 25

What causes apoptotic abnormalities?

Answer 25

Ischaemic injury

Viral infections

Question 26

What is the morphology of apoptosis?

Answer 26

Cells shrink (pyknosis)

Chromatin condensation- nucleus clumps and breaks up

Cytoplasmic blebs- cytoplasm breaks up

Macrophages- come in to hoover

Question 27

What is the cause of cellular ageing?

Answer 27

Many causes;
-oxidative stress- free radical damage
-accumulation of metabolism by-products;
>lipofuscin