Cellular Adaptation

Question 1

Cellular Adaptation

Answer 1

Change in cell structure and/or function in response to changes inside the body

Question 2

Atrophy

Answer 2

A decrease or shrinksge in cellular size

Ex; muscle tissue/ muscle shrinking after a cast

Question 3

Atrophy Causes and exmaples

Answer 3

• Disuse
• decreased nervous/ hormonal stimulation
• ischemia leading to cell hypoxia
  - cell isnt getting enough oxygen ( neurons in the brain shrink)

Question 4

Atrophy patho

Answer 4

• Decreased number of organelles ( lower mitochondria & atp)
• decreased actin/myosin

Question 5

Hypertrophy

Answer 5

An increase in the size of cells & thicker (compensates to increase work load)

Question 6

Hypertrophy causes and exmaples

Answer 6

-Increased Workload
ex. working out; building skeletal muscle (not making more muscle just getting bigger)
-Increased hormonal stimulation
Hypertrophy of cells in uterus during hormonal increase in pregnancy

Question 7

Hypertrophy Patho

Answer 7

• NOT swelling of the cell
• Increase in actin/myosin
• Increase in organelles (more mito, atp and myosin)

Question 8

Hyperplasia

Answer 8

An increase in the NUMBER of cells, through cell division and mytosis

Question 9

Hyperplasia causes and examples

Answer 9

-Compensatory hyperplasia;
allows certsin organs/tissues to regenerate
ex: scrape skin; cell division occurs and grows back
- Hormonal hyperplasia
Occurs chiefly in estrogen-dependent organs
ex; uterine cells growing
-Pathologic hyperplasia
Abnormal proliferation or normal cells usually as the result of excessive hormone situation
ex; benign prostatic hyperplasia (enlarged prostate) from an increase in testosterone

Question 10

Hyperplasia Patho

Question 11

Metaplasia

Answer 11

Abnormal change in the tissue, reversible replacment of on mature cell type by another - usually insult or injury

Question 12

Metaplasia Cause and Examples

Answer 12

-Prolonged Insult

Columnar cells change shape. become less specified multiple layer of skin cells formed

Question 13

Metaplasia patho

Answer 13

ADAPTATION of injury to protect

Question 14

Dysplasia (atypical hyperplasia)

Answer 14

Abnormal changes in the size, shape and organization

of mature cells- Cells less normal, one step closer to cancer

Question 15

Dysplasia Cause and example

Answer 15

-DNA mutations - inherited, random or due to cell injury (e.g. free radical injury)
ex; Cervical dysplasia seen on a pap smear (from hpv) ..dysplasia is a pre-cancerous condition

Question 16

Hypoxic Injury

Answer 16

Lack of oxygen in the tissues leading to altered cell metabolism and function

Question 17

Hypoxic Injury causes

Answer 17

-Decreased oxygen CONTENT blood (hypoxemia)
respiratory oxygen such as asthma/ high altitude

-Decreased Oxygen CARRYING CAPACITY of blood (anemia)
low hemoglobin count

-Decreased blood FLOW to the tissue (ischemia)
ex; blocked arterial, not allowing blood flow (blokced blood flow)

Question 18

Reperfusion injury

Answer 18

Reperfused: Restoring flow of blood to organ or tissue

If Hypoxic tissue is reperfused, cell injury because introducing oxygen to tissue has been hypoxic causes formation of reactive oxygen species (ROS) (i.e. free radicals)

hypoxic cells produce xanthine oxydase >
> when O2 is reintroduced >
> reascts w/ O2 to create oxygen free radicals

Question 19

Free Radical Injruy

Answer 19

Free radicals are molecules that have an unpaired electron (unstable molecule)

Question 20

Free Radical causes and formation

Answer 20

• Absorption of extreme energy sources
  absorp. of ionizing radiation breaks apart molecules and liberates free radicals

-Endogenous, usually oxidative, rxns from nomal metabolic processes
ex; ATP production in ETC

• Inflammation
  ex. phagocytosis..kills things in free radicals, the rest not killed is dumped into the body

-Enzymatic metabolism or exogenous chemicals/drugs
ex; chemotherapy agents

-other sources- cigarette smoke, alcohol,transfate, etc.

Question 21

Free Radical Effects

Answer 21

In high levels, FR cause “oxidative stress” cell injury
-DNA damage
FR can fragment strands of DNA causing mutations/ireeversible injury to cells

-Fragmented Proteins
enzymes and structural proteins

-Lipid Peroxidation
attracted to carbon double bonds in lipid moelcules. & breaks apart this bond {lipid very stable,FR love them}

Question 22

Free Radical Clinical Example

Answer 22

-FR injury and aging
-FR injury causes disease
>CANCER
fr> damage dna > mutate DNA > form cancer tumors

> Cardiovascular disease
damage to endothelial lining by FR circulating in the blood

Question 23

Molecules that inactive Free Radicals

Answer 23

ANTIOXIDANTS

• Vitamin A & E
• Betacarotene
• lypocene
• flavonoids
• omega 3 & 6 fatty acids

Question 24

Necrosis (Cell death)

Answer 24

Loss of plasma membrane structure, swelling of organelles, mitochondrial dysfunction leading to death of cell {primarily autodigestion}

Question 25

Coagulative Necrosis

Answer 25

-Caused by protein denaturing & coagulation typically has a lot of protein initially -Occurs with hypoxic injury to kidneys, heart and adrenal glands

Question 26

Liquefactive Necrosis

Answer 26

-Tissue becomes soft and liquefies Little tissue present -Occurs with hypoxic injury to brain tissue and bacterial infections

Question 27

Caseous Necrosis

Answer 27

- Combination of coag & liqeufactive necrosis cause by tuberculosis - primarily in the lungs

Question 28

Fat necrosis

Answer 28

-Caused by release of lipase ex; lipase auto digests, fat takes over space where tissue was -most commonly occurs in breast,liver, pancreas

Question 29

Gangrenous necrosis

Answer 29

-Death of a series of tissues from severe hypoxic injury ex; leg or toe (lack of blood supply to limb) -GAS GANGRENE occurs with anaerobic bacterial infections.. gas build up in dead/dying tissue

Question 30

Gas gangrene

Answer 30

occurs with anaerobic bacterial infections | -gas build up in dead/dying tissue

Question 31

Apoptosis

Answer 31

Programmed Cell death | -Cell turns on internal mechanisms to initiate self-destruction

Question 32

Signals that induce Apoptosis

Answer 32

- Extracellular signals (death ligands, withdrawl of hormones, toxic agents, etc) - intracellular signals

Question 33

Mechanisms of Apoptosis

Answer 33

- Nucleus condenses and cell shrinks - > activation of intracellular enzymes that breakdown structural proteins and DNA - > Apoptic bodies are ingested by neighboring cells and local phagocytes (WBC) or just degenerate **NOTE; inflammatory response NOT stimulated

Question 34

Clinical examples of apoptosis

Answer 34

-Apoptosis during embryonic development ex; embryo to child .. fingers unwebbed -Apop. in cancer cells 50% of cancer has mutation in apop gene