Altered Cell Biology

Question 1

stress (insult)

Answer 1

stimulus that upsets normal homeostasis

Question 2

Compensation

Answer 2

the body’s attempt to maintain normal homeostasis under stress

Question 3

cell injury

Answer 3

result of a stimulus in excess of a cell’s immediate adaptive response

Question 4

reversible cell injury

Answer 4

injury which does not kill the cell (makes it stronger)

Question 5

apoptosis

Answer 5

• clean, controlled cell death
• cell breaks apart into apoptotic bodies that then get phagocytozed by other cells
• membrane is not ruptured
  
  • no enzymes released
  • does not trigger immune response
  • does not show in blood test

Question 6

Necrosis

Answer 6

• messy, uncontrolled cell death
• cell membrane breaks
  
  • causes release of enzymes
  • causes inflammatory response
  • shows in blood test

Question 7

atrophy

Answer 7

decrease in the size of cells

Question 8

hypertrophy

Answer 8

increase in the size of cells

Question 9

hyperplasia

Answer 9

increase in number of cells

Question 10

metaplasia

Answer 10

• change of the cell from one type to another
  
  • can be normal or abnormal
• ex. GERD, cells of esophagus change over time to become more like the cells of the stomach from all the acid.

Question 11

dysplasia

Answer 11

• abnormal cells that are not necesarily cancer, but can be
• change from normal to abnormal
  
  • ex: a wort

Question 12

neoplasia

Answer 12

• abnormal disorganized growth, if it forms a mass, is called a tumor
• *different from dysplasia because it is larger in size

Question 13

how does heart muscle get bigger?

Answer 13

• only 1% more cardiomyocytes are made by stem cells per year.
• the individual cardiomyocyte cells grow bigger, making the overall muscle bigger.

Question 14

What are the four common themes in cell injury?

Answer 14

1. ATP depletion
2. free radicals and reactive oxygen species
3. Increase in intracellular Ca++
4. Defects in plasma membrane

Question 15

ATP depletion

Answer 15

• lack of O2 greatly decreases ATP production
• lack of ATP prevents the Na/K channels from working

Question 16

Free radicals and reactive oxygen species

Answer 16

• highly reactive chemicals containing oxygen
• Cause oxidation of membranes and other structures
• particularly problematic with reperfusion

Question 17

Increase in intracellular Ca++:

what can cause it?

what does it cause?

Answer 17

• low ATP and Na+ gradient prevent removal of Ca++ and release of Ca++ from mitochondria and ER
• Ca++ activates many enzymes
• at very high levels Ca++ signals apoptosis

Question 18

What is the process of a cell being injured by ischemia?

(flow chart)

Answer 18

Question 19

what changes happen to a cell that makes the injury irreversible?

Answer 19

• rupture of lysosoves and autolysis
• defects in the cell membrane
• karyolysis
• karyorrhexis

Question 20

karyolysis and karyorrhexis

Answer 20

breaking up of chromatin and the cell nucleus/DNA

Question 21

hypoxia

Answer 21

low tissue oxygent level

Question 22

anoxia

Answer 22

very low tissue oxygen level, no oxygen

Question 23

hypoxemia

Answer 23

low blood oxygen tension

Question 24

how does anemia effect hypoxia and hypoxemia?

Answer 24

An anemic person can have a normal oxygen tension (because all their hemoglobin are 100% saturated) but low tissue oxygen level because they don’t have enough hgb to bring enough O2 to the tissues.

Question 25

ischemia

Answer 25

• insufficient blood supply to tissue or organ
  
  • insufficient blood supply to entire body: shock
• nothing dies, tissue will be fine once it is reperfused.

Question 26

infarction

Answer 26

ischemia that leads to necrosis

Question 27

embolism

Answer 27

blood clot that moves

(an embolism ambles)

Question 28

thrombus

Answer 28

a blood clot that clots the same place where it was made.

Question 29

Superoxide dismutase

Answer 29

• enzyme that breaks down the superoxide radical (O₂^-) into either regular oxygen or hydrogen peroxide.
• If you exercise vigorously, you will have more SOD

Question 30

Catalase

Answer 30

• enzyme that converts hydrogen peroxide (H₂O₂) into water

Question 31

glutathione peroxidase

Answer 31

• a type of enzyme who’s main function is to prevent an organism from oxidative damage (from giving up an electron to the free radical)
• Can be reduced back to glutathione reductase
• The ratio of reduced glutathione and oxidized glutathione in a cell can measure the cell’s oxidative stress

Question 32

coagulative necrosis

Answer 32

• cell death caused by ischemia or infarction
• some of the cell structure is preserved for a few days because the injury effects the lysosomal enzymes
  
  • this gives a clumping, coagulative appearance

Question 33

liquefactive necrosis

Answer 33

• a type of necrosis that turns the tissue into liquid
• usually caused by bacteria or fungus
• the affected cell is completely broken down. Once it has been cleaned up by the white blood cells, it leaves a hole or empty space

Question 34

Caseous Necrosis

Answer 34

• a form of cell death where the tissue looks cheese-like
• caused by TB

Question 35

Fat necrosis

Answer 35

• caused when digestive enzymes break down fat
  
  • seen in pancreatitis when the enzymes get to the fat of the omentum
• Lipase breaks fatty acids from triglycerides
  
  • lipase takes up Ca++ (causing low calcium) and makes soaps

Question 36

Telomere

Answer 36

The end part of the chromosome; gets shorter with every replication.

Question 37

telomerase

Answer 37

• found in germ cells and stem cells
• prevents the telomeres from shortening when replicated.

Question 38

elevated levels of ALT and AST wil signify ______

Answer 38

that liver cells are dying

Question 39

elevated levels of alkaline phosphatase and GGT wil signify _______

Answer 39

problems with the cells of the bile ducts