Exam 1: Cellular injury, stress, & genetics

Question 1

Atrophy

Answer 1

Cellular adaptation in which cells revert to the smaller size. It
is the shrinking of skeletal muscle seen in paralysis or even
inactivity from bed rest.
Acts to decrease energy requirements

Conditions it occurs:
1. disuse
2. denervation
3. loss of endocrine stimulation
4. inadequate nutrition
5. ischemia or decreased blood flow

Question 2

Hypertrophy

Answer 2

An increase in the individual cell size and often mass where there is an enlargement of functioning tissue. It increases the cell’s functional components which leads to greater metabolic demand and energy needs

Question 3

Physiologic hypertrophy

Answer 3

Enlarged muscle that is adequately perfused and supplied with
blood flow. There is proportional increase in cell size and
enhancement of coronary blood supply. (Working out and muscles larger)

Question 4

Pathological hypertrophy

Answer 4

An increase in cellular size without an increase in the supportive structures necessary for the enlarged cells increase in metabolic demand. Seen in hypertension or heart failure. LV hypertrophy

Question 5

Hyperplasia

Answer 5

Increase in the number of cells in the tissue or gland, generally stimulated by hormonal or compensatory cellular mechanism.

normal: increase in breast gland cells when a
woman is pregnant
maladaptive: a keloid

Question 6

Metaplasia

Answer 6

Replacement of one cell type by another cell type generally due to environmental conditions

chronic inflammation

(Gastroesophageal reflux is a good example of this and can lead to cancer)

Question 7

Dysplasia

Answer 7

Chronic inflammation or precancerous condition dysplastic cells vary in size, shape and architectural organization compared to healthy cells. (Cervical dysplasia example)

Classic precursor to cancer.

Question 8

Neoplasia

Answer 8

Uncoordinated, uncontrolled proliferative cell growth that is cancerous like a tumor

Question 9

Ischemia

Answer 9

Inadequate blood flow

Question 10

Hypoxia

Answer 10

Oxygen deprivation, blood cannot deliver oxygen to cells this
can be body or region

-emia: low ox content in blood
-ia: low ox supply in body

↓oxygen →anaerobic metabolism →use up glycogen stores →↑lactic acid →alter cell member → failure Na+/K+ pump → ↓intracellular K+ →↑Na+ and H20→cell swells→ ↓mitochondrial function

Question 11

Infarction

Answer 11

Also known as ischemic necrosis, it is the death of tissue due to prolonged ischemia

Question 12

oxidative stress

Answer 12

Cell injury induced by free radicals
Causes changes in gene and protein expression
Reactive oxygen species exceeds the ability of the body to neutralize and eliminate
plays role in development of cancer and other disease processes

Question 13

free radicals

Answer 13

Have a single unpaired electron in an outer orbit that creates instability and reactivity with adjacent molecules they react with constituents of the cell’s plasma causing oxidative degradation
generated from: excessive UV light, radiation, chemicals/drugs, reperfusion

Question 14

antioxidants

Answer 14

block free radicals and prevent or delay cell damage
vitamins A, C, E, and zinc

Question 15

Apoptosis

Answer 15

Genetically programmed degenerative change that causes cell death no adverse effects on the body a reduction in cell size, intact plasma membrane but an altered structure, no adjacent inflammation

Question 16

Necrosis

Answer 16

Cellular death due to stressors of insults that overwhelm the cell’s ability to survive, it is irreversible an enlarged cell size, disrupted plasma membrane, cellular contents leak out of cell and frequent adjacent inflammation

Question 17

Gangrene

Answer 17

Occurs when a considerable mass of tissue undergoes necrosis

Question 18

Seyle’s stress response theory

Answer 18

Explains the body’s response to acute, intermittent stressors. Stressors can be positive or negative. The adaptive ability is the way in which individuals manage the stress and reduce the stressor’s effect on their life.

Homeostasis is the equilibrium between various physiologic parameters, adaptive ability depends on coping mechanisms, reaction to a stress is individual

3 stages:
1. alarm - fight or flight response
2. resistance - recovering from illness
3. exhaustion - chronic exposure increases risk for disease

Question 19

McEwen’s Stress response theory

Answer 19

Stress is a routine part of daily life not episodic or a crisis

Frequent stressors change the body’s physiologic balance and create new set points, allostasis load accumulates because of four mechanisms:
repeated stressful experiences
inability of the individual to adapt to stress
prolonged reaction to a stressor
inadequate response to a stressor

Question 20

Allostasis

Answer 20

The dynamic state of balance that changes to exposure to stressors

Question 21

Allostatic load

Answer 21

The wear and tear on the body systems caused by stress reactions

Question 22

Gene

Answer 22

Specific group of nucleotides of the DNA helix that carry a code for protein

Segment of DNA on chromosome

gene locus refers to location of a gene on a chromosome

Question 23

Karyotype

Answer 23

Picture of the chromosomes that are contained within the DNA of a species, human karyotype as 23 pairs of chromosomes

Question 24

Mendelian genetics

Answer 24

Inherited traits are passed from parents to offspring. The Punnett square is a predictable pattern in transmission of a single gene, not used for multifactorial inheritance. Used with autosomal dominant, autosomal recessive, and sex linked.

Question 25

Somatic cells

Answer 25

46 chromosomes formed through mitosis

Question 26

Gametes

Answer 26

23 chromosomes and called haploid cells formed through meiosis

Question 27

Homozygous vs Heterozygous

Answer 27

homo- Both alleles on each corresponding chromosome are the same
hetero- The alleles on corresponding chromosomes are not the same

aa vs Aa

Question 28

Teratogens

Answer 28

Agents that may or may not cause mutations but can damage a developing fetus

Question 29

Phenotype

Answer 29

How the genetic traits manifest in the individual the actual, physical, or somatic expression of the genotype

Question 30

Genotype

Answer 30

The genetic makeup of a person
Genetic info stored in the sequence of base pairs

Question 31

Penetrance

Answer 31

ratio of how many persons have the phenotype as compared to those that have the genotype

likeliness of getting the trait

ex:
75 have clinical features
100 have mutation
75/100= .75 75% penetrance

Question 32

Expressivity

Answer 32

A disorder can be expressed by symptom severity, variation of a phenotype

variability of the level of the trait

Question 33

Multifactorial diseases

Answer 33

Involvement of many genes and environment aspect

Question 34

aneuploidy

Answer 34

Abnormal number of chromosomes, a cell that does not contain 23 pairs of chromosomes
Can be sex-linked (abnormal # of sex chromosomes)

Question 35

Trisomy

Answer 35

Three copies of one chromosome or gain of a chromosome
Downs

Question 36

Monosomy

Answer 36

Missing one chromosome from a pair. All autosomal monosomies are not compatible with life. Monosomy of the X chromosome is compatible with life.

Question 37

Carrier

Answer 37

A person, who is heterozygous for a recessive trait and
does not manifest it, has a recessive allele, but the
dominant allele silences it. Example Dd.

Question 38

Disruption of intracellular calcium homeostasis

Answer 38

causes cell injury

Normal A & P: ICF Ca+ low compared to ECF & maintained through calcium/magnesium exchange system

Patho: Ischemia and toxins lead to an increase in ICF Ca+ which leads to further cell membrane damage and ATP depletion

Question 39

Body’s responses to stress

Answer 39

Adrenal medulla/hypothalamus - releases norepinephrine and epinephrine
Posterior pituitary - releases antidiuretic hormone (ADH)
Anterior pituitary - releases adrenocorticotropic hormone (ACTH)
Adrenal Cortex - releases cortisol and aldosterone

Question 40

Transcription

Answer 40

Messenger RNA (mRNA) is formed from DNA; takes place in nucleus

Question 41

Translation

Answer 41

Synthesis of a protein using the mRNA template in cytoplasm
-Supported by rRNA and tRNA