Physiology Subject Review Flashcards
The motor neuron and muscle fiber connect at the neuromuscular junction. What space is crossed by the neurotransmitter to send the message from the neuron to the muscle fiber?
a. Motor end plate
b. Sarcolemma
c. Synaptic cleft
d. Synaptic vesicle
c. Synaptic cleft
A patient sustains a myocardial infarction (heart attack) that damages the ventricular septum of the heart. What effect on the heart is most likely to be seen immediately after the heart attack?
a. Blood flowing from the left side of the heart to the right
b. Changes in the electrical conduction of the heart
c. Damage to the valves of the heart
d. Reduction in blood pressure
b. Changes in the electrical conduction of the heart
At what point of fetal development does sexual differentiation begin?
a. 4-5 weeks
b. 6-8 weeks
c. 9-12 weeks
d. 14-16 weeks
c. 9-12 weeks
Some postsynaptic receptors cause excitation upon activation, where others cause inhibition. What is associated with excitation?
a. Activation of ionotropic receptors
b. Decreased conduction through chloride channels
c. Increased conductance of potassium ions out of the neuron
d. Opening of chloride ion channels through the postsynaptic neuronal membrane
b. Decreased conduction through chloride channels
The renal system is able to regulate the rate of renal blood flow and glomerular filtration rate (GFR) over a wide range of blood pressures. Which description applies to an intrinsic mechanism for autoregulation of blood flow?
a. Acts to reduce renal blood flow to limit fluid loss
b. Promotes reabsorption of sodium by the nephron
c. Reduces excess filtrate formation to maintain normal GFR
d. Stimulates the release of renin
c. Reduces excess filtrate formation to maintain normal GFR
Arteriosclerosis is a leading cause of hypertension.
Which variable that influences blood pressure and blood flow does arteriosclerosis affect?
a. Blood viscosity
b. Blood volume
c. Cardiac output
d. Compliance
d. Compliance
What cells of the nephron in the kidneys will secrete hydrogen ions or bicarbonate to regulate acid-base balance in the body?
a. Intercalated cells
b. Mesangial cells
c. Principal cells
d. Proximal convoluted tubular cells
a. Intercalated cells
How is eukaryotic translation different from prokaryotic translation?
a. Eukaryotic translation is not coupled with transcription
b. Eukaryotic translation does not require ribosomes
c. Eukaryotic translation does not require elongation factors
d. Eukaryotic translation does not require a start codon to initiate translation
a. Eukaryotic translation is not coupled with transcription
How do general transcription factors work?
a. Binding DNA to position RNA polymerase at its promoter
b. Bringing ribonucleotides to RNA polymerase at its promoter
c. Bringing ribosomes to DNA
d. Removing non-essential proteins from the RNA polymerase promoter
a. Binding DNA to position RNA polymerase at its promoter
Case:
A 10-year-old boy is admitted to the hospital with chest pain. An ECG is done revealing a normal sinus rhythm.
Question:
This is an indication that electrical excitation originates from what location?
a. Sinoatrial node
b. Atrioventricular node
c. Bundle of His
d. Purkinje fibers
a. Sinoatrial node
What hormone affects bone metabolism by directly stimulating osteoclast activity?
a. Calcitonin
b. Growth hormone
c. Parathyroid hormone
d. Thyroxine
c. Parathyroid hormone
Lipodystrophy is a condition characterized by atrophy or genetic deficiency of the adipocytes. What would a patient with lipodystrophy present with?
a. Excessive fat storage
b. Excessive plasma protein formation in the liver
c. Inability to desaturate fatty acids
d. Inability to transport lipid components in the blood
a. Excessive fat storage
What enzyme is secreted by the kidneys to increase blood pressure in response to low blood flow through the kidneys?
a. Angiotensin I
b. Angiotensin II
c. Angiotensinogen
d. Renin
d. Renin
Cardiac output is the volume of blood the heart pumps in one minute. If a person’s heart rate is 80 beats per minute, moving 75 mL from the left ventricle with each contraction, what is their cardiac output?
a. 4.5 L/min
b. 5 L/min
c. 5.5 L/min
d. 6 L/min
d. 6 L/min
CO = SV x HR
Stroke volume of 75 mL x heart rate of 80 bpm = 6000 mL/minute, or 6 L/minute.
Atropine is a drug designed to paralyze the cholinergic nerve endings of the myenteric plexus. What impact is atropine likely to have on peristalsis?
a. Increasing peristalsis because the cholinergic nerve endings will be paralyzed
b. Nearly blocking peristalsis because myenteric plexus activation is required
c. Not directly impacting peristalsis because the parasympathetic nervous system is still functioning
d. Slightly decreasing peristalsis because intestinal contents will redirect around the myenteric plexus
b. Nearly blocking peristalsis because myenteric plexus activation is required
A woman has recurrent viral infections. Her physician orders a series of tests and discovers that the level of the cells most responsible for fighting virus-infected cells is depleted. What cells are depleted in this patient?
a. Thrombocytes
b. Mast cells
c. Schwann cells
d. Cytotoxic T lymphocytes
e. Erythrocytes
d. Cytotoxic T lymphocytes
What substance uses osmosis to cross the cell membrane?
a. Oxygen
b. Potassium
c. Sodium
d. Water
d. Water
What substance crosses the cell membrane through simple diffusion?
a. Carbon dioxide
b. Glucose
c. Potassium
d. Sodium
a. Carbon dioxide
What symptom is most likely to present in a patient with hyperthyroidism?
a. Cold intolerance
b. Constipation
c. Depression
d. Weight loss
d. Weight loss
The process of chemical digestion breaks down large food molecules into smaller units that can be absorbed in the alimentary canal. The digestion of protein begins in which part of the gastrointestinal tract?
a. Large intestine
b. Mouth
c. Small intestine
d. Stomach
d. Stomach