Ch.4- Altered Cellular and Tissue Biology

Question 1

What is cellular adaption?

Answer 1

a reversible event involving a structural or functional response to both physiologic (normal) conditions and pathologic (adverse) conditions. Cells adapt to meet physiologic demands and stress in an effort to maintain a steady state called homeostasis.

Question 2

How successful are pathological adaptions?

Answer 2

adaptions to pathological conditions are usually only temporarily successful

Question 3

What are the types of adaptive changes?

Answer 3

atrophy, hypertrophy, hyperplasia, dysplasia, and metaplasia

Question 4

What is atrophy?

Answer 4

A decrease in cellular size caused by aging, disuse, or insufficient blood supply. Insufficient hormonal or neural stimulation can also cause atrophy. ER, mitochondria, and microfilaments decrease with atrophy. Mechanisms predisposing the cell to atrophy include decreased protein synthesis or increased catabolism, or both. If enough cells shrink, the organ size can too.

Question 5

Physiologic cause of atrophy?

Answer 5

normal in early development, senile atrophy of geriatrics, or breast and ovaries after menopause. Also decreased muscle because lack of exercise

Question 6

pathologic atrophy

Answer 6

results from decrease in workload, pressure, use, blood supply, nutrition, hormonal/neural stimulation

Question 7

What is hypertrophy

Answer 7

increase in the size of cells in response to mechanical stimuli (stretching, pressure, or volume overload) and results in increased size of the affect organ.

Question 8

physiologic hypertrophy

Answer 8

results from increased demand (exercise), stimulation by hormones, growth factors, uterus when pregnant

Question 9

pathologic hypertrophy

Answer 9

results from chronic hemodynamic overload, cardiac hypertrophy bc of increased workload

Question 10

What is hyperplasia?

Answer 10

increase in the number of cells caused by an increased in mitosis (cellular division).

Question 11

physiologic hyperplasia

Answer 11

compensatory= enables organs to regenerate
hormonal= in organs that respond to endocrine hormonal control (increase in breast tissue during preg and lactation)

Question 12

pathologic hyperplasia

Answer 12

hormonal= abnormal proliferation of normal cells (wound healing or viral infection), (increased in lymph nodes tissue with chronic infectious state)

Question 13

What is metaplasia?

Answer 13

reversible replacement of one mature cell type with another less mature cell type(could lead to dysplasia), associated with tissue damage, repair, regeneration, reprogramming of stem cells or undifferentiated mesenchymal cells. (smoking changes the resp cells, esophagus cells undergo a change from stra to colum bc of acid)

Question 14

What is dysplasia?

Answer 14

abnormal changes in size, shape, organization of mature cells (nuclear and cytoplasmic abnormalities and distorted material) (it is considered atypical rather than a true adaption).may be reversible if triggering stimulus is removed. tissues appear disorderly, but it is not cancer (if left untreated it will become cancer).

Question 15

What is cellular injury?

Answer 15

Occurs if a cell is unable to maintain homeostasis (normal or adaptive state) secondary to insult or stress, it is either reversible (cells recover) or irreversible (cells die). Injury to cell and extracellular matrix leads to tissue and organ damage. This injury affects the structural pattern of disease.

Question 16

What biochemical events contribute to cell injury and death?

Answer 16

ATP depletion, accumulation of oxy and radical oxy (ROS causes membrane damage), increased Ca in cell and loss of Ca, mitochondrial damage, membrane damage, protein folding defects

Question 17

What are the most common forms of cell injury?

Answer 17

ischemic injury, hypoxic injury, ischemia-reperfusion injury, oxidative stress or accumulation of oxygen-derived free radical, and chemical injury

Question 18

What is hypoxic injury?

Answer 18

lack of sufficient oxygen in cells and is the most common cause of cellular injury. it could be caused by ischemia (reduced blood supply), reduced oxygen content in air, loss of hemoglobin, decreased production of red blood cells, dis of cardio and resp sys, poisoning of oxidative enzymes (cytochromes) in the cell
anoxia= lack of oxy caused by obstruction
ex. stroke, heart attack, diabetes, anemic

Question 19

What is ischemia-reperfusion injury?

Answer 19

cell injury and death caused by restoration of blood flow and oxy in ischemic state. The mechanisms include oxidative stress, increased intracellular calcium conc, inflammation, and complement activation
ex. putting in stent, doing a bypass

Question 20

How do free radicals cause cellular injury?

Answer 20

Free radicals have an unpaired electron making the molecule unstable. To become stable, they may form chemical bonds with proteins, lipids, and carbs located within membranes and nucleic acids (DNA), causing injury. The damaging effects is called oxidative stress. Mechanisms include lipid peroxidation, protein alteration, dna damage, and mitochondrial effects.

Question 21

How do chemicals and toxins cause cell injury?

Answer 21

xenobiotics are toxic, mutagenic, carcinogenic (ex. carbon tetrachloride, lead, carbon monoxide, ethanol, mercury, social or street dugs like over the counter and prescribed drugs). Potential mechanisms for injury include oxidative stress, hear shock proteins, dna damage, hypoxia, er stress, mental stress, inflammation, and osmotic stress

Question 22

What is an environmental toxin?

Answer 22

air pollution is the largest environmental health risk, millions of deaths bc of indoor and outdoor pollution.

Question 23

How do heavy metals associate with cell injury?

Answer 23

lead, mercury, cadmium, and arsenic cause cell damage by affecting dna repair mechanisms, tumor suppressor functions, and signal transduction pathways

Question 24

How does ethanol (alcohol) cause cell injury?

Answer 24

it alters nutritional status causing the metabolism of acetaldehyde. Fetal alcohol spectrum disorders are a range of health effects or disorders of prenatal alcohol exposure. maternal ingestion can be catastrophic for the developing fetus (changes dna)

Question 25

Talk about intentional and unintentional injuries

Answer 25

more common among men and higher rates among blacks

Question 26

Blunt force injuries

Answer 26

result of the application of mechanical force to the body, resulting in tearing, shearing, or crushing of tissues. These include contusions (bruises), lacerations (tears or rips in the skin), and fractures of bone. The most common cause include motor vehicle accidents and falls

Question 27

Sharp force injuries

Answer 27

result of cutting or piercing. examples include incised, stab, puncture, and chopping wounds

Question 28

gunshot wounds

Answer 28

may be either penetrating (bullet is retained in the body) or perforating (bullet exists out of body). The most important factors determining the appearance of a gunshot injury are whether it is an entrance or an exit wound and the range at which the bullet was fired.

Question 29

What are asphyxial injuries?

Answer 29

caused by a failure of cells to receive or use oxygen, it could be caused by suffocation (choking), strangulation (hanging, ligature, and manual), chemical (carbon monoxide, cyanide, and hydrogen sulfide), or drowning

Question 30

How can infection cause cellular injury?

Answer 30

when a disease enters it causes invasion and destruction, releases toxins, and could lead to a hypersenitivity response. also, activation of inflammation and immunity produces phagocytes and biochemical reactions (histamines, antibodies, lympho, comple sys products, and proteases)

Question 31

How can cellular accumulations cause cellular injury (infiltration)?

Answer 31

normal cellular substances are water, protein, carbs, and lipids, but having too much can cause cell injury and an accumulation of abnormal substances like endogenous (made in the body) and exogenous (got from outside the body) is bad

Question 32

How can accumulations result in the cell?

Answer 32

insufficient removal of normal substances bc of altered transport, accumulation of abnormal sub bc of defects, inadequate metabolism of endogenous sub bc of lack of lysosomal enzyme, harmful exogenous materials.

Question 33

what is a kind of manifestation of cellular injury?

Answer 33

bruising! its extravasated red cells-> phagocytosis of red cells by macrophages->hemosiderin and iron free pigments

Question 34

Describe the cellular swelling that occurs with injury?

Answer 34

oncosis is a type of cell death that occurs bc of cellular swelling with water, occurs as a result of a failure of the transport mechanisms to regulate water flow into and out of the cell.

Question 35

cellular death: what is the difference between necrosis and apoptosis?

Answer 35

necrosis (passive) is rapid loss of plasma membrane structure, organelle swelling, mitochondrial dysfunction, and lacks typical features of apoptosis. it can be regulated or programmed, and autolysis (autodigestion) occurs. Apoptosis (active) is programmed cell death and is (mostly) normal but can be pathogenic.

Question 36

What are the four types of necrosis?

Answer 36

coagulative, liquefactive, caseous, and fatty. occur in diff tiss and under diff disease circumstance

Question 37

What is coagulative necrosis?

Answer 37

protein denaturation, albumin is transformed from a gel transparent state to a firm opaque substance, infarct (small area of dead tiss from fail of blood supply) kidneys, heart, and adrenal glands

Question 38

what is liquefactive necrosis?

Answer 38

the tiss becomes liquid, the neurons and glial cells of the brain, hydrolytic enzymes, bacterial infection (staphylococci, streptococci, and e.coli)

Question 39

what is caseous necrosis?

Answer 39

tuberculous pulmonary infection (in lungs), combination of coagulation and liquefactive necrosis

Question 40

what is fat necrosis?

Answer 40

breast, pancreas, and other abdominal organs, action of lipases

Question 41

What is gangrenous necrosis?

Answer 41

death of tissue from severe hypoxic injury (often in lower extremities), dry vs wet gangrene, and gas gangrene (clostridium)

Question 42

What are examples of gangrenous necrosis?

Answer 42

thrombosis or embolism (in intestine bc of obstruction), strangulated hernia (gets stuck and loses oxy), volvulus (small bowel gets twisted), intussusception (large bowel, no elasticity, bowel folded in and gets no oxy), gangrene (diabetics often have too much sugar which takes energy and small vessels get damaged).

Question 43

what is autophagy?

Answer 43

a self-destructive and a survival mechanism. when cells are starved or nut deprived, it recycles digested contents (delivered to lysosomes for degradation). it declines and becomes less efficient as cells age, which contributes to the aging process.

Question 44

Describe aging?

Answer 44

it is hard to distinguish between physiological (normal) and pathological (abnormal) changes associated with aging. investigators are focused on genetic, inflammatory, oxidation, and metabolic origins of aging. Important factors in aging include increased damage to cells, reduced capacity for mitosis, reduced ability to repair dna damage, and defective nitrogen balance

Question 45

what is frailty?

Answer 45

common is older adults characterized by overall weakness, decreased stamina, and functional decline. this leaves the individual vulnerable to falls, functional decline, disability, disease, and death. sarcopenia and cachexia (muscle wasting) are common of aging

Question 46

what is somatic death?

Answer 46

death of the entire organism, postmortem changes are diffuse, predictable, and do not involve inflammatory response.

Question 47

what are the seven stages of death?

Answer 47

cessation of respiration and circulation and dilations of the pupils: pallor mortis, algor mortis, rigor mortis, livor mortis, putrefaction, decomposition, skeletonization. depending on the environment involving the bones, fossilization may occur (rare).