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Exam One - Key Content Points That Were Frequently Missed
Cells and Genes
1. Effect of loss of ATP on the cell during ischemia – pages 51-52
- Ischemia (reduced blood flow) is the most common cause of hypoxia. Often caused by gradual
narrowing of arteries and complete blockage by blood clots.
- A reduction in ATP levels causes the plasma membranes sodium-potassium pump and sodium-
calcium exchange to fail, which leads to an intracellular accumulation of sodium and calcium,
resulting in cellular swelling and diffusion of potassium out of the cell. Because all cells are
bathed in a fluid rich in calcium ions, cell membrane damage allows rapid movement of calcium
intracellularly. The movement of water and ions into the cell causes early dilation of the ER. The
dilation then causes the ribosomes to detach from the rough ER, resulting in reduced protein
synthesis. If hypoxia continues, the entire cell becomes swollen with increased concentrations of
Na and H2O and Cl, and decreased K.
2. Trisomy 21 and risks for cognitive disorders – page 144
- Most well-known example of aneuploidy in an autosome = down syndrome, or trisomy 21
- IG of 25-70, low nasal bridge, epicanthal folds, protruding tongue, low set ears, poor muscle tone,
short stature.
- By 40 years of age, those with down syndrome usually always develop symptoms similar to
Alzheimer’s because the Alzheimer’s disease is located on chromosome 21.
3. Risk of cystic fibrosis disease with both parents as carriers
- Cystic Fibrosis is common among Europeans, occurring about once in every 2500 births. Rare in
Asians. CF is a single gene disorder.
- 1 in 25 whites carries 1 copy of an allele that can cause CF… an individual must be homozygous
for a recessive allele to express the disease (carriers are typically normal).
- Marriage between related individuals often causes recessive disorders (more likely to share the
same recessive disease-causing alleles).
- Males and females are equally affected. Consanguinity is sometimes present. The disease is seen
in siblings but not usually their parents. On average, ¼ of the offspring of carrier parents will be
affected.
4. Chronic ethanol ingestion and nutritional deficits – Pages 68-70
- Alcohol dehydrogenases (ADHs) converts ethanol to acetaldehyde and aldehyde
dehydrogenases… causing facial flushing, nausea, lightheadedness, palpitations people with
these genes are much less likely to become alcoholics due to the unpleasant effects.
, 2
- Chronic alcoholism – most significant activity occurs in the liver. Hepatic changes initiated by
acetaldehyde include inflammation, deposition of fat, enlargement of the liver, interruption of
microtubular transport of proteins and their secretion, increase in intracellular water, decrease in
fatty acid oxidation in the mitochondria, increase in membrane rigidity and development of acute
liver necrosis.
- Can cause cirrhosis = associated with portal HTN and increased risk of hepatocellular carcinoma.
- A large intake of alcohol has enormous effects on nutritional status. Liver and nutritional
disorders*
o Nutritional deficiencies include magnesium, vitamin B6, thiamine and phosphorus.
Chronic intake may adversely affect the brain and peripheral nerves.
o Folic acid deficiency – alters folic acid homeostasis by decreasing intestinal absorption of
folate, increases liver retention f folate and increase the loss of folate through urinary and
fecal excretion. *contributes to fetal alcohol syndrome.
Fluids and Electrolytes
1. Infant susceptibility to loss of total body water (TBW)
- In newborn infants, TBW is about 70% to 80% of body weight because infants store less fat. In the
immediate postnatal period, a physiologic loss of body water occurs, equivalent to about 5% of
body weight as the infant adjusts to a new environment.
- Infants are susceptible to changes in TBW because of their high metabolic rate and potential for
evaporative fluid loss attributable to their greater body surface area in proportion to total body
size.
- Loss of fluid from diarrhea can represent a significant proportion of body weight in infants… renal
mechanisms may not be mature enough so dehydration can develop rapidly.
2. High insulin dose and serum potassium – pgs. 114-115
- K plays a major role in neuromuscular function. Dietary K is absorbed in the GI tract.
- Insulin contributes to the regulation of plasma K levels by stimulating the NaK ATPase pump,
which promotes the movement of K into the liver and muscle cells simultaneously with glucose
transport. Intracellular movement of K prevents an acute hyperkalemia related to food intake.
Insulin is used to treat hyperkalemia. Low levels of K result from the administration of insulin
when K is already depressed. It is essential to monitor K levels in patients receiving insulin
treatment (ex. Diabetes).
- Insulin and aldosterone deficiency, acidosis and strenuous exercise facilitate the shift of K out of
the cells.
3. How are calcium and phosphorus levels related? – pg. 119
- Calcium and phosphorus concentrations are rigidly controlled. They are related by the product of
calcium and phosphate concentrations, which is constant. IF the concentration of one ion increases
or decreases, that of the other increases or decreases.
Exam One - Key Content Points That Were Frequently Missed
Cells and Genes
1. Effect of loss of ATP on the cell during ischemia – pages 51-52
- Ischemia (reduced blood flow) is the most common cause of hypoxia. Often caused by gradual
narrowing of arteries and complete blockage by blood clots.
- A reduction in ATP levels causes the plasma membranes sodium-potassium pump and sodium-
calcium exchange to fail, which leads to an intracellular accumulation of sodium and calcium,
resulting in cellular swelling and diffusion of potassium out of the cell. Because all cells are
bathed in a fluid rich in calcium ions, cell membrane damage allows rapid movement of calcium
intracellularly. The movement of water and ions into the cell causes early dilation of the ER. The
dilation then causes the ribosomes to detach from the rough ER, resulting in reduced protein
synthesis. If hypoxia continues, the entire cell becomes swollen with increased concentrations of
Na and H2O and Cl, and decreased K.
2. Trisomy 21 and risks for cognitive disorders – page 144
- Most well-known example of aneuploidy in an autosome = down syndrome, or trisomy 21
- IG of 25-70, low nasal bridge, epicanthal folds, protruding tongue, low set ears, poor muscle tone,
short stature.
- By 40 years of age, those with down syndrome usually always develop symptoms similar to
Alzheimer’s because the Alzheimer’s disease is located on chromosome 21.
3. Risk of cystic fibrosis disease with both parents as carriers
- Cystic Fibrosis is common among Europeans, occurring about once in every 2500 births. Rare in
Asians. CF is a single gene disorder.
- 1 in 25 whites carries 1 copy of an allele that can cause CF… an individual must be homozygous
for a recessive allele to express the disease (carriers are typically normal).
- Marriage between related individuals often causes recessive disorders (more likely to share the
same recessive disease-causing alleles).
- Males and females are equally affected. Consanguinity is sometimes present. The disease is seen
in siblings but not usually their parents. On average, ¼ of the offspring of carrier parents will be
affected.
4. Chronic ethanol ingestion and nutritional deficits – Pages 68-70
- Alcohol dehydrogenases (ADHs) converts ethanol to acetaldehyde and aldehyde
dehydrogenases… causing facial flushing, nausea, lightheadedness, palpitations people with
these genes are much less likely to become alcoholics due to the unpleasant effects.
, 2
- Chronic alcoholism – most significant activity occurs in the liver. Hepatic changes initiated by
acetaldehyde include inflammation, deposition of fat, enlargement of the liver, interruption of
microtubular transport of proteins and their secretion, increase in intracellular water, decrease in
fatty acid oxidation in the mitochondria, increase in membrane rigidity and development of acute
liver necrosis.
- Can cause cirrhosis = associated with portal HTN and increased risk of hepatocellular carcinoma.
- A large intake of alcohol has enormous effects on nutritional status. Liver and nutritional
disorders*
o Nutritional deficiencies include magnesium, vitamin B6, thiamine and phosphorus.
Chronic intake may adversely affect the brain and peripheral nerves.
o Folic acid deficiency – alters folic acid homeostasis by decreasing intestinal absorption of
folate, increases liver retention f folate and increase the loss of folate through urinary and
fecal excretion. *contributes to fetal alcohol syndrome.
Fluids and Electrolytes
1. Infant susceptibility to loss of total body water (TBW)
- In newborn infants, TBW is about 70% to 80% of body weight because infants store less fat. In the
immediate postnatal period, a physiologic loss of body water occurs, equivalent to about 5% of
body weight as the infant adjusts to a new environment.
- Infants are susceptible to changes in TBW because of their high metabolic rate and potential for
evaporative fluid loss attributable to their greater body surface area in proportion to total body
size.
- Loss of fluid from diarrhea can represent a significant proportion of body weight in infants… renal
mechanisms may not be mature enough so dehydration can develop rapidly.
2. High insulin dose and serum potassium – pgs. 114-115
- K plays a major role in neuromuscular function. Dietary K is absorbed in the GI tract.
- Insulin contributes to the regulation of plasma K levels by stimulating the NaK ATPase pump,
which promotes the movement of K into the liver and muscle cells simultaneously with glucose
transport. Intracellular movement of K prevents an acute hyperkalemia related to food intake.
Insulin is used to treat hyperkalemia. Low levels of K result from the administration of insulin
when K is already depressed. It is essential to monitor K levels in patients receiving insulin
treatment (ex. Diabetes).
- Insulin and aldosterone deficiency, acidosis and strenuous exercise facilitate the shift of K out of
the cells.
3. How are calcium and phosphorus levels related? – pg. 119
- Calcium and phosphorus concentrations are rigidly controlled. They are related by the product of
calcium and phosphate concentrations, which is constant. IF the concentration of one ion increases
or decreases, that of the other increases or decreases.
