4 - Altered Cellular and Tissue Biology

Question 1

Cellular Injury

Answer 1

Cell is unable to maintain homeostasis, can be reversible or irreversible

Question 2

Physiological

Answer 2

Adaptive

Question 3

Pathogenic

Answer 3

Causing disease

Question 4

Atrophy

Answer 4

Decrease in cellular size

Question 5

Hypertrophy

Answer 5

Increase in cellular size

Question 6

Hyperplasia

Answer 6

Increase in number of cells

Question 7

Metaplasia

Answer 7

Replacement of one cell type with another

Question 8

Dysplasia

Answer 8

Deranged cellular growth

Question 9

Hypoxic Injury

Answer 9

Single most common cause of cellular injury, results from lack of oxygen to the cell.
-reduced 02 to mitochondira
-reduced production of ATP=less energy
-Increased accumulation of H+, breakdown of mitochondiral membrane
-increase in intracellular H+
-Loss of membrane potential –> necrosis

Question 10

Ischemia

Answer 10

Inadequate blood supply

Question 11

Ischemia-reperfusion injury

Answer 11

Additional injury caused by restoration of blood flow and oxygen
Caused by oxidative stress + inflammation + increased Ca2+
-decrase in ATP, failure of Na+/K+ pump (uses 80% of cell’s ATP)
-Change in osmolarity –> cellular swelling/shrinking

Question 12

Free Radicals

Answer 12

Atom missing an electron and will attack healthy atom to obtain a replacement electron
-by products of healthy metabolism –> Reactive Oxygen Species (ROS))

Question 13

Oxidative stress

Answer 13

Not enough antioxidants to break down current free radicals –> cellular damage

Question 14

Antioxidants

Answer 14

Atom that has an extra electron in its outer ring that it freely gives to a free radical “neutralizing” it

Question 15

Reactive Oxygen Species (ROS)
-What 3 things does it cause?

Answer 15

Electrically uncharged atom or group of atoms having an unpaired electron that causes:
1. Lipid peroxidation
2. Alteration of proteins
3. Alteration of DNA

Question 16

Lipid Peroxidation

Answer 16

Free radical attack lipids –> membrane damage

Question 17

Xenobiotics

Answer 17

substances foreign to the body

Question 18

4 Common Xenobiotics

Answer 18

1. Lead -most common, can pass through BBB to fetus
2. Carbon monoxide - oxygen deprivation, attatches to mitochondira 20-30x higher affinity than O2
3. Ethanol (alcohol) -Liver damage, nutritional deficiencies, J-shaped effect curve
4. Mercury - global threat to humans and environment

Question 19

On-target toxicity

Answer 19

direct damage caused to cells by chemical agents, injure celss by directly combining with critial substances

Question 20

Asphyxiation

Answer 20

Failure of cells to recieve or use oxygen

Question 21

Suffocation

Answer 21

Systemic hypoxia, no air exchange

Question 22

Strangulation

Answer 22

compression/closure of airway, causes cerebral hypoxia

Question 23

Drowning

Answer 23

Fluid fills lungs, no oxygen exchange. Fluid can pass through alveolar/capillariy interface –> electrolyte changes in blood

Question 24

Hyperbaric Chamber

Answer 24

Treatment for CO poisoning, pressure increases the binding of O2 to Hb instread of CO

Question 24

Chemical Asphyxiation -2 Causes

Answer 24

Prevention of oxygen delivery to cells or its utilization 1. Carbon monoxide (binds to hemoglobin) 2. Cyanide (blocks utilization of oxygen at ETC)

Question 25

Contusion

Answer 25

Crushing injurty to muscle, mild = bruise

Question 25

Laceration

Answer 25

Cut with irregular edges

Question 26

Fracture

Answer 26

Broken or shattered bones

Question 27

Incision

Answer 27

Sharp straight wound

Question 28

Incised Wound

Answer 28

Wound is longer than it is deep

Question 29

Stab Wound

Answer 29

Wound is deeper than it is long

Question 30

Puncture wound

Answer 30

Sharp point but not sharp edges

Question 31

Infectious Injury -3 Mechanisms

Answer 31

Invasion of a pathogen resulting in disease -Invasion and destruction -toxin production -hyper-immune reactions

Question 32

Apoptopsis

Answer 32

Normal cell death, occurs as part of growth and development. Remains taken away by immune system

Question 33

Autophagy

Answer 33

Consumption of a cell's own contents for fuel to oppose starvation

Question 34

Necrosis

Answer 34

Swelling and bursting of cell membrane, -due to disease, injury, ischemia -Occurs at cellular level

Question 35

Coagulative necrosis (+ where?)

Answer 35

Cause: ischemia or infaction -coagulation is due to protien denaturation, -cells can be revived if o2 supplied within 20 mins Found in --> kidney, heart

Question 36

Caseous necrosis

Answer 36

Dead tissue resembles clumped cheese Cause: tuberculosis Danger, dead cells envelop other cells, decreases lung space Location --> Lungs

Question 37

Liquefactive necrosis

Answer 37

Ischemic injury to neurons and glial cells Transforms tissue to liquid, causes infarction -often from bacterial infection (Streptococci, E. coli) Location --> Brain

Question 38

Fatty Necrosis

Answer 38

Location --> breasts, abdominal organs Action of lipases, usually harmless, left alone and body will absorb it

Question 39

Gangrenous necrosis

Answer 39

Severe hypoxic injuryn to major arteries, often in lower leg -becomes medium for bacterial growth (anaerobic)

Question 40

Gas ganrene

Answer 40

Due to clostridium (anaerobic bacteria) infection, produces gas that is fatal if it enters blood and diminishes oxygen-carrying capacity of RBC

Question 41

Oncosis

Answer 41

Cell death due to swelling -Injury --> hypoxia --> ATP decreases --> Na+ enters cell, K+ leaves cell, causing water enter as it follows sodium -Osmotic pressure increases, more water moves into cell -cisternae of ER distend, rupture, form vacuoles--> etensive vacuolation -Hydropic degeneration

Question 42

Sarcopenia

Answer 42

Progressive/generalized loss of skeletal muscle mass and strength, (sarco:flesh/penia:deficient) often occurs with aging