Exam #1

Question 1

Describe oxidative phosphorylation.

Answer 1

Process that occurs in the mitochondria. Oxidative phosphorylation is when energy is produced from carbohydrates, fats, and proteins and is transferred to ATP. ATP is most efficient in the presence of oxygen (aerobic metabolism) since oxygen provides the cell with a much more powerful method for extracting energy from the food molecules. When generating ATP through the anaerobic process, glycolysis is used. Glycolysis occurs outside of the mitochondria and is not as efficient as aerobic metabolism. Glycolysis makes 1 ATP while aerobic metabolism makes 3 ATP.

Question 2

What causes hydrostatic pressure? Where is the fluid in the blood vessels moving?

Answer 2

Hydrostatic pressure is caused by the pushing of fluid across a semipermeable cell membrane. In blood vessels, hydrostatic pressure is caused by the pumping action of the heart. When this occurs in the blood vessels, the fluid is leaving the blood vessel and entering into the interstitial fluid.

Question 3

What causes colloid osmotic pressure? Where is the fluid in the blood vessels moving?

Answer 3

Colloid osmotic pressure is primarily due to plasma proteins in the blood, specifically albumin. If plasma proteins are lost or if production is decreased, osmotic pressure will decrease and fluid will remain in the interstitial space instead of being returned to the capillaries. Plasma proteins are too large to easily cross the capillary walls and the effect of this is that it helps keep fluid from leaking out of the capillaries. Osmotic pressure tends to pull fluid into the capillaries.

Question 4

Differentiate the three types of active mediated transport.

Answer 4

Uniport is when a single molecule moves in one direction

Symport is when two molecules move simultaneously in the same direction

Antiport is when two molecules move simultaneously in opposite directions

Question 5

Describe the Na K pump.

Answer 5

The Na K pump is an example of an antiport system. It is an active transport that moves 3 molecules of Na+ out of the cell and 2 molecules of K+ into the cell for every ATP molecule expended. Both Na+ and K+ are moving against the concentration gradient.

*An antiport system is when 2 molecules move simultaneously in opposite directions (i.e. Na+ and K+). When cell is at rest, Na+ is mostly outside the cell while K+ is inside of the cell. Upon activation, Na+ moves inside the cell while K+ leaves. The Na+ K+ pump helps get the cell back to its resting state.

Question 6

What transport systems are examples of endocytosis?

Answer 6

Pinocytosis and phagocytosis are two forms of endocytosis.

Endocytosis moves molecules into the cell by enfolding the substance into the plasma membrane and forming a vesicle that moves into the cell.

Pinocytosis involves ingestion of fluids or cellular drinking.

Phagocytosis is ingestion of large particles such as bacteria or cellular eating

Question 7

Describe the ionic basis of the action potential.

Answer 7

Rest- At rest the inside of the cell is negatively charged (-70 mV)

1. Stimulate- Na+ enters the cell until reaching threshold (-55 mV)
2. Depolarization- cell membrane potential increases to (+30 mV) as more Na+ enters cell.
3. Na+ gates close and K+ gates slowly open, completing depolarization.
4. Repolarization begins when the Na+ gates close and K+ gates open. It is complete once the K+ gates close.
5. Hyperpolarization- “Overshoot” (~ -90 mV) occurs, because exceeding the resting potential prevents the cell from simultaneously receiving other stimuli.
6. Return to Rest- The cell returns to resting membrane potential (-70 mV) by pumping Na+ out and K+ into the cell.

Question 8

Differentiate absolute and relative refractory periods.

Answer 8

Absolute refractory period: occurs during most of the action potential (depolarization and repolarization) the cell is not able to respond to another stimulus.

Relative refractory period: occurs towards the end of repolarization, when the K+ gates are beginning to close, a stronger than normal stimulus can cause a reaction.

Question 9

What cells reproduce through mitosis?

Answer 9

Somatic cells, which are all cells except sperm and egg cells

Question 10

What cells reproduce through meiosis?

Answer 10

Sperm and egg cells

Question 11

What is the mutant allele (A or a) in autosomal dominant disorders? Autosomal recessive disorders?

Answer 11

In autosomal recessive disorders the mutant or recessive allele is “a”. In this disorder both genes have to be abnormal for the disorder to be expressed.

*In autosomal dominant disorders the abnormal allele is dominant “A” over the normal allele “a”.

Question 12

What are clinical manifestations of neurofibromatosis?

Answer 12

Neurofibromatosis is an autosomal dominant disorder where cell growth in the nervous system is affected causing tumors to form on nervous tissue, including the brain, spinal cord and nerves. Symptoms typically appear in early childhood in the most common form and the telltale sign is the presence of coffee-colored birthmarks called “cafe-au-lait” spots. After puberty tumors tend to develop under the skin and sometimes internally. Mild symptoms may include hearing loss, vision loss, learning impairment, severe pain, and heart and blood vessel complications. Severe disability may occur due to nerve compression by the tumors. Other features can include high BP, curvature of the spine, speech problems and the development of epilepsy.

Question 13

What are clinical manifestations of Marfan Syndrome?

Answer 13

Marfan Syndrome is when too much of the protein fibrillin is produced. Symptoms include skeletal changes such as very long arms, legs, fingers, toes. Individuals may also have a deeply depressed sternum or scoliosis.

Question 14

Which diseases are autosomal dominant, autosomal recessive, and X-linked?

Answer 14

Autosomal Dominant disorders- Huntington Disease, Neurofibromatosis, Marfan Syndrome.

Autosomal Recessive disorders- Sickle Cell Anemia, Cystic Fibrosis, Phenylketonuria (PKU)

X-Lined disorders- Duchenne Muscular Dystrophy, Hemophilia

Question 15

What does being a “carrier” or having the “trait” mean?

Answer 15

Being a carrier/having the trait means that you yourself do not have the disorder but you have the ability to pass it on to your offspring.

Question 16

What abnormality is present in sickle cell anemia? In hemophilia?

Answer 16

Sickle cell anemia arises when there is a mutation in a gene that tells the body to make hemoglobin; hemoglobin S is produced. RBCs become rigid, sticky, and shaped like crescent moons when oxygen levels are decreased. This causes clumps in the blood vessels that block blood and oxygen from circulating throughout the body.

Hemophilia is an X-linked disorder that causes low levels of clotting factors. This provokes excessive/prolonged bleeding.

Question 17

What are the clinical manifestations for cystic fibrosis?

Answer 17

Common symptoms of those with CF are include chronic coughing (dry or with phlegm), recurring chest colds, wheezing and SOB, frequent lung infections like pneumonia or bronchitis, and poor growth or weight gain even when having a good appetite and constipation.

Question 18

What is the treatment for phenylketonuria (PKU)?

Answer 18

People with PKU must follow a low protein diet throughout their lives as their treatment.

*Patients with PKU must follow a low protein diet as the gene that codes the enzyme responsible for breaking down the amino acid, phenylalanine, is mutated. This causes a build up of phenylalanine that can lead to multiple health problems including mental retardation.

Question 19

What are the clinical manifestations of Duchenne muscular dystrophy?

Answer 19

Duchenne muscular dystrophy is characterized by progressive muscle weakness. Signs and symptoms usually begin when the child reaches walking age and include frequent falls, difficulty getting up from a lying or sitting position, large calf muscles, walking on toes, waddling gait, trouble keeping balance, muscle pain/stiffness, and learning disabilities.

Question 20

What is the genetic abnormality in Down Syndrome, Turner Syndrome, and Klinefelter Syndrome?

Answer 20

Down: trisomy, three chromosome 21’s

Turner: monosomy X or the presence of a single X chromosome instead of two resulting in 45 chromosomes in these females

Kline: results in males with two X chromosomes and one Y, for a total of 47 chromosomes

Question 21

What are the clinical manifestations of Turner Syndrome and Klinefelter Syndrome?

Answer 21

Kleinfelter’s is XXY (two X chromosomes) and Turner’s is XO (one X chromosome instead of two)

*The clinical manifestations of Turner’s syndrome include females having a wide carrying angle of the arms, low hairlines and webbing of the neck, ears being slightly lower than normal, eyes having a downward tilt, jawbones slightly less prominent, and a droop to one or both eyes.

Klinefelter’s syndrome can have clinical manifestations of a male appearance with female characteristics, like wide hips, enlarged breasts, high voice, and sparse body hair. The males will also be sterile with small testicles.

Question 22

Give examples of atrophy, hyperplasia, metaplasia, dysplasia.

Answer 22

Atrophy - a decrease in the size of cells. An example of physiologic atrophy is the shrinking of the thymus gland as childhood progresses. An example of pathologic atrophy is the shrinking of skeletal muscle when a limb is placed in a cast due to immobilization.

Hyperplasia - an increase in the number of cells. An example of physiologic hyperplasia is when part of the liver is removed and the remaining cells regenerate. An example of pathologic hyperplasia is the enlargement of the prostate gland (benign prostatic hyperplasia) which can cause urinary difficulties in men.

Metaplasia - the reversible replacement of one mature cell type by a another, sometimes less mature, cell type. This change occurs due to an irritant in the environment. For example, Barrett’s metaplasia occurs in the lower esophagus due to irritation from acid reflux. When the acid reflux is controlled and the lower esophagus is free from the irritation of stomach acid, the metaplasia can be reversed.

Dysplasia - the abnormal change in in size, shape, and organization of mature cells that can be preceded by hyperplasia or metaplasia. Common sites that are affected include the cervix and the respiratory tract. For example, a pap smear is done to determine if cervical cells have changed or become dysplastic.

Question 23

What is occurring at the cellular level when a patient has hypoxia?

Answer 23

There is a decrease in ATP production, causing sodium and potassium to remain in the cell. Which can cause disruption in the cellular metabolic process ultimately leading to cell death.

• Cell death occurs because calcium is being accumulated and this causes enzymes to activate.

Question 24

What is occurring at the cellular level when free radicals are present?

Answer 24

1. )Destruction of polyunsaturated fats.
2. )Protein alterations that cause transport mechanisms in the cell membrane to fail.
3. ) There is a reduction in protein synthesis
4. ) Mitochondrial damage, causing calcium to be out into the cytosol which can lead to cell death.
   * The cell’s plasma membrane is damaged, causing increased permeability.

Question 25

What ways can parents limit a child’s exposure to lead?

Answer 25

1. ) Test suspected areas for lead both interior and exterior.
2. ) Don’t scrape or use heat to remove lead
3. ) Use cold water when making bottles or intaking faucet water as warmer temperatures are known to have high lead levels.
4. ) Wet mop every 2-3 weeks until lead is completely covered on floors.
5. ) Don’t allow children to play in dirt contaminated with lead.
6. ) Cover lead based paint with latex or oil based paint.
   * Parents can limit lead exposure by having their child live in a home built after 1978, the year lead paint was banned from interior house usage.

Question 26

How much alcohol and what kind of alcohol are safe during pregnancy?

Answer 26

There is no known amount of alcohol that is safe to drink during pregnancy. As well as no safe time for a pregnant woman to consume alcohol. A woman should not drink alcohol while pregnant or when she might get pregnant.

Question 27

What physical abnormalities are associated with fetal alcohol syndrome?

Answer 27

Physical abnormalities include palpebral fissures (narrow eye openings), flat midface with a short nose, indistinct philtrum (smooth area without ridges between the nose and upper lip), thin upper lip, micrognathia (small jaw), flat nasal bridge, epicanthal folds (skin folds of the upper eye that cover the inner corner of the eye), small head size, short stature, and low body weight.

Question 28

What causes jaundice?

Answer 28

Jaundice is caused by an excessive number of red blood cells being broken down. This in turn means the liver cannot conjugate or gather the bilirubin and it accumulates in the skin and sclera. Jaundice can also occur from liver disease. Liver disease may cause the liver to be unable to handle normal amounts of bilirubin.

Question 29

What causes the different types of necrosis?

Answer 29

Necrosis is the result of irreversible cell damage. There are four different types: coagulative, liquefactive, caseous, and fat necrosis.

Coagulative necrosis location: kidneys, heart, adrenal glands

Coagulative necrosis cause: hypoxia from severe ischemia or chemical injury

Liquefactive necrosis location: brain

Coagulative necrosis cause: ischemic injury

Caseous necrosis location: lungs
Caseous necrosis cause: tuberculosis

*This is a combination of coagulative & liquefactive necrosis which causes tissue to become soft and granular.

Fat necrosis location: breast, pancreas, abdominal structures
Fat necrosis cause: lipases break down triglycerides

Question 30

Differentiate wet and dry gangrene.

Answer 30

Dry gangrene is usually the result of coagulative necrosis caused by lack of blood flow to tissues. It is not typically caused by an infection. It often involves the hands and feet. The tissues become dry and brown/black in color. They eventually fall off.

Wet gangrene is the result of liquefactive necrosis. Rather than drying out, the tissues become swollen and glistening. Wet gangrene usually involves an infection, which can spread through the body and become life threatening.

Question 31

Differentiate apoptosis and necrosis.

Answer 31

Apoptosis is a programmed cell death that occurs in about 10 billion times a day in adults whereas, necrosis occurs when severe persistent stress causes irreversible cell injury

*Apoptosis causes phagocytes to quickly remove the dead cell, causing no inflammatory response. Necrosis causes the cell to swell and burst, spilling its contents on neighboring cells. Necrosis causes an inflammatory response.

Question 32

Differentiate algor mortis, livor mortis, and rigor mortis.

Answer 32

Body temperature falls about 1-1.5 degrees Fahrenheit during algor mortis. Blood settles throughout the body in dependent areas, creating a blush color, during livor mortis. Muscles stiffen during rigor mortis. It starts with the small muscles and moves to bigger ones. After 36-62hrs, the body becomes flaccid again.

*it is 1-1.5 degrees per hour until the body is at room temperature for algor mortis.

Question 33

What is Starling’s Law of the Capillaries?

Answer 33

Capillary pressure forces fluid out of the capillary with hydrostatic capillary pressure. Interstitial fluid pressure forces fluids into capillary. Plasma colloid osmotic pressure pulls fluid into the capillaries. Interstitial fluid colloid osmotic pressure pulls fluid out of the capillaries. The net filtration pressure in the interaction between these which pushes fluid out of the capillary

Question 34

What are the four main causes of edema?

Answer 34

The four main causes of edema:

1. increased hydrostatic pressure in the capillaries; is caused by venous obstruction and salt and water retention. Venous obstruction is from thrombophlebitis, standing for long periods of time, and tight clothing around extremities. Salt and water retention occurs with heart and renal failure when too much fluid is in the vessels and its pushed out into the capillaries
2. Decreased osmotic pressure in the capillaries; If there is not enough plasma protein in the blood the osmotic pressure will decrease and fluid will remain in the interstitial fluid and not return to the capillaries.
3. increased capillary permeability in the capillaries; When the capillaries are more permeable from inflammation and immune responses fluid and proteins leaves the blood and into the interstitial pulling more fluid
4. Obstruction or removal of the lymphatic system; Lymphatic system removes excess fluid from interstitial space and returns it back to circulation but if the lymphatic system is damaged or removed fluid can not be removed and fluid will accumulate

Question 35

What happens when the renin-angiotensin-aldosterone system is activated?

Answer 35

Angiotensin l gets converted to Angiotensin ll, which is a strong vasoconstrictor that causes blood pressure to rise. Aldosterone causes sodium and water retention which will also cause high blood pressure and potassium is lost from the kidneys. When blood pressure decreases, the sodium levels decrease and potassium levels will increase. Angiotensin is formed when kidneys release renin.

Question 36

When is atrial natriuretic peptide released?

Answer 36

• the atria pressure increases due to an increase in blood volume. The increased pressure is then what causes the release of the natriuretic peptide
• the natriuretic peptides are a natural antagonists to the renin-angiotensin-aldosterone system

Question 37

What happens when antidiuretic hormone (ADH) is released?

Answer 37

A diuretic causes the kidney to excrete more urine, so antidiuretic hormone (ADH) does the opposite. ADH causes a decrease in urination. ADH causes the kidneys to hold onto water or keep more water in the body, this in turn causes the blood to become more dilute.

Question 38

What is normal serum sodium level? What fluid movement occurs with hyponatremia and hypernatremia?

Answer 38

135-145mEq/L

hyponatremia (less than 135 mEq/L): A loss of sodium or water excess and with less sodium in the blood, the blood osmolality decreases and water starts to move from the blood into the cells.
* due to the movement of water into the cells; cellular swelling occurs.

hypernatremia (more than 145 mEq/L): A gain of sodium or loss of water can result in hypernatremia. The more sodium in the blood, the bloods osmolality increases and water starts to move from the cells into the blood.
*due to the movement of water into the blood: cellular shrinkage occurs

Question 39

What is normal serum potassium level? What clinical manifestations occur with hypokalemia and hyperkalemia?

Answer 39

The normal potassium level in blood is between 3.5 and 5.0 mmol per liter. Hypokalemia can make the patient feel muscle weakness, cramping,twitching or can become paralyzed. Heart rhythms can also become abnormal. Hyperkalemia can cause heart attack or even death.

Hyperkalemia (5.0< serum potassium)

Clinical Manifestations: “-kalemia = EKG changes”

Patients with mild hyperkalemia may be restless/irritable, and experience intestinal cramping and/or diarrhea.

Severe hyperkalemia is characterized by muscle weakness, ranging from a loss in tone to paralysis.

Cardiac changes include tall, peaked T- waves which increase in prominence with the severity of imbalance.

(6-7) Earliest visible EKG changes, T-wave peak instead of rounded/flat.

(7-8) “Eiffel tower” T-wave is peaked with a symmetrical, narrow base.

(>8) Widened QRS complex with large T-wave peak

Question 40

What is the primary disturbance in each of the four acid base imbalances?

Answer 40

Metabolic Acidosis Primary Disturbance: When HCO3 levels are less than 22 mEq/L

Respiratory Acidosis Primary Disturbance: When PaCO2 levels are greater than 45 mm Hg

Metabolic Alkalosis Primary Disturbance: When HCO3 levels are greater than 26 mEq/L

Respiratory Alkalosis Primary Disturbance: When PaCO2 levels are less than 35 mm Hg

Question 41

What happens to CO2 levels when the rate and depth of respirations change?

Answer 41

When the rate and depth of respirations increase, carbon dioxide is absorbed into the blood to be removed, so they are lowered. And when respirations decrease it goes back to normal

Question 42

How does the body compensate in each of the four acid base imbalances?

Answer 42

Metabolic Acidosis Compensation:

Respiratory compensation via hyperventilation decreases PaCO2.

Metabolic compensation via the kidneys retaining HCO3 and excreting H+.

Respiratory Acidosis Compensation:

Metabolic compensation via the kidneys retaining HCO3 and excreting H+.

Metabolic Alkalosis Compensation:

Respiratory compensation via hypoventilation raises the PaCO2.

Metabolic compensation via the kidneys retaining H+ and excreting HCO3.

Respiratory Alkalosis Compensation:

Metabolic compensation via the kidneys retaining H+ and excreting HCO3.

Question 43

What is the etiology of each of the four acid base imbalances? (See tab under Focus 2-Acid Base Imbalances)

Answer 43

Metabolic Acidosis: Renal failure, ketosis, aspirin poisoning, over-production of lactic acid

Respiratory Acidosis: Chronic pulmonary disease, depression of respiratory center from drugs

Metabolic Alkalosis: Loss of gastric juice, chloride depletion, excess corticosteroid hormones, ingestion of bicarbonate or other antacids

Respiratory Alkalosis: Severe, anxiety with hyperventilation, central nervous system disease, hypoxia, pulmonary imbalances