Apoptosis and Necrosis

Question 1

two ways cells can die

Answer 1

Apoptosis and Necrosis

Question 2

Necrosis

Answer 2

• bad
• occurs when a cell is damaged by an external force, such as poison or injury
• triggers an inflammatory response that can damage nearby cells.

Question 3

Apoptsis

Answer 3

-good
-occurs when the cell receives an internal signal to self-destruct
-does not trigger an inflammatory repones.

Question 4

apoptosis initiation (way in which cells initiates apoptosis)

Answer 4

-mitochondrial pathway
-death receptor pathway

Question 5

mitochondrial pathway

Answer 5

apoptosis triggerd by internal signals from the mitochondrial which releases cytochrome C

Question 6

Death Receptor Pathway

Answer 6

apoptosis triggered by external signals from immune system

Question 7

apoptosis process

Answer 7

once activated by either pathway, caspase enzymes become activated, resulting in the destruction of the cell such as:
-digestion of cell proteins, organelles and DNA
-membrane blebbing and breakage: as the cytoskeleton is digested, the structural integrity of the cell is weakened.

Question 8

Apoptosis clean up

Answer 8

signals are sent to phagocytes to destroy the apoptosis bodies.
-cell shrinks, chromatin condenses
-budding
-apoptosis bodies are phagozytosed (an eating cell)

Question 9

necrosis clean up

Answer 9

• cell swells
  -cell becomes leaky, blebbing (holes form in the membrane)
  -cellular and nuclear lysis causes inflammation.

Question 10

Apoptosis dot point

Answer 10

• caused by body
  -beneficial to organism
  -series of biochemical steps leading to cell destruction
  -can help to prevent diseases such as tumors
  -shrinking of cytoplasm, condensation of nucleus, fragmenting of DNA
  -blebbing of plasma membrane without loss of integrity
  -energy dependent

Question 11

necrosis dot point

Answer 11

-caused by external factors such as infection
-harmful to organism
premature death of cells and living tissue
-can cause diseases such as chronic inflammation
-swelling of cytoplasm and mitochondria
-loss of membrane integrity
-no energy required.

Question 12

apoptosis function

Answer 12

a natural and essential process for healthy functioning, eliminating DNA-damaged, superfluous, or unwanted cells

Question 13

apoptosis malfunction

Answer 13

-regulation of apoptosis can sometimes go wrong, causing a number of health issues
-sometimes the wrong cells self destruct
-sometimes the ones that should be destroyed remain intact.

Question 14

excessive apoptosis

Answer 14

-may result in the loss of vital tissues
-excessive number of neurons is called neurodegeneration.
Alzheimer’s is a disease caused by an excessive number of apoptosis of brain cells

Question 15

decreased apoptosis

Answer 15

-mutations in specific genes can cause the cell cycle to be disrupted and apoptosis to not occur
-can cause unregulated cell division and abnormal growth
-unregulated cell division can develop into cancer