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test questions, 3&4
What physiological change would you expect if you traveled to the mountains high above sea level?
decreased partial pressure of oxygen (PO2) in the alveoli
The ____ capillaries of the glomerulus allow most molecules to pass into the capsule, but ______ are retained and pass to the smaller efferents.
Fenestrated; erythrocytes
Bronchodilation can be stimulated by...
Epinephrine
Skeletal muscle Ca2+ signaling
Depolarization along the T-tubule causes voltage-gated Ca2+ channels to open on the sarcoplasmic reticulum
Smooth muscle Ca2+ signaling
Ca2+ entering the cell triggers the release of Ca2+ from the sarcoplasmic reticulum
Cardiac Muscle Ca2+ signaling
Depolarization along the T-tubule causes voltage-gated Ca2+ channels to open on the cell membrane
Of the 8-10L of fluid that enters the GI tract every day...
only about 150mL is excreted as part of the feces
Which molecule binds and activates platelets after a blood vessel has been injured?
Collagen
Where in the digestive system is mucus secreted?
The oral cavity; small intestine; stomach; large intestine
These vessels are the main site of variable resistance in the circulatory system:
arterioles
Which is NOT an accessory gland to the digestive system?
Enteric nervous system
Which of the following contributes to the asynchronous contraction of heart atria and ventricles?
Delay of action potential traveling from the SA node to the apex.
Which of the following is NOT true of cardiac function?
The CNS controls heart rate
The importance of the plateau phase of the action potential of contractile cells in...
preventing arrhythmia
The primary function of bile is to...
aid in the digestion of lipids
The primary exchange surface of the lungs is at the level of the...
alveoli
The uppermost part of the _____ is composed of skeletal muscle, while the lower 1/2 is entirely smooth muscle, which roughly corresponds to the respective voluntary and involuntary control of these sections
esophagus
What is primarily responsible for human inhalation and exhalation?
The contraction and relaxation of the diaphragm
Pre-historic insects could be _____, bc _____ atmospheric oxygen created a _____ concentration gradient.
Larger; more; steeper
Which section of the nephron is impermeable to water?
ascending Loop of Henle
Ventricles depolarize...
from the apex up
Autorhythmic cells....
are also called pacemakers because they set the heart rate
When the bladder becomes full, stretch receptors send signals via sensory neurons to the spinal cord. This causes...
opening of the internal sphincter; inhibition of the tonic stimulation that is normally contracting the external sphincter; parasympathetic neurons to fire, which triggers contraction of the smooth muscle of the bladder
Pulmonary arterial pressure is higher than the systemic arterial pressure (aorta).
False
Urine is carried to the urinary bladder by the...
ureters
The P wave of an ECG corresponds to...
the depolarization of the atria.
Which is NOT considered to be a primary function of the respiratory system?
Regulation of water balance
How does gas exchange occur in your body?
Passive diffusion
What best describes how alcoholic beverages affect your water balance?
Ethanol inhibits ADH, which leads to the production of large volumes of dilute urine
Smooth muscle cells
An autonomic neuron releases neurotransmitters that bind to receptors on the sarcolemma and generate an action potential. Cell membrane depolarization releases Ca2+ from the sarcoplasmic reticulum. Myosin binding sites are revealed on actin. Contraction occurs along the entire length of the myosin filament
Cardiac autorhythmic cells
The action potential is generated intrinsically via ion funny (IF) channels. Voltage-gated Ca2+ channels open in the cell membrane triggering rapid depolarization and IF channels close. Ca2+ channels close and K+ channels open. IF channels open.
Cardiac contractile cells
The action potential enters from an adjacent cell. Voltage-gated Na+ channels open causing rapid depolarization. Voltage-gated K+ channels open beginning cellular repolarization. Voltage-gated Ca2+ channels open. Ca2+ binds receptors in the SR. Ca2+ is released from the SR. Myosin binding sites are revealed in actin. The sarcomere contracts. Ca2+ channels close. Slow K+ channels open.
Skeletal muscle cells
The action potential is generated by neurotransmitters produced by a somatic motor neuron binding receptors in the sarcolemma. Voltage-gated Na+ channels open along the sarcolemma and depolarization causes voltage-gated Ca2+ channels to open along the T-tubules which are mechanically coupled on Ca2+ channels on the SR. Myosin binding sites are revealed on actin. The sarcomere contracts
At the SYSTEMIC capillaries, oxygen (O2) and carbon dioxide (CO2) move _____ their concentration gradients. ______ moves into the capillaries and ____ moves out of the capillaries.
down; Co2; O2
If the membrane of cardiac muscles in the sinoatrial (SA) node were more permeable to K+, you would predict:
heart rate will decrease
Veins carry de-oxygenated blood to the heart, except in the...
pulmonary system
Glucose is normally found in the _____, but absent from the ________.
filtrate; urine
In the stomach, the mucosal layer secretes H+ and Cl- ions. This is necessary because...
the digestive enzyme pepsin is only activated at very low pH
The inner lining of blood vessels is called...
endothelium
Compared to arteries, the velocity of blood flow through the capillaries is....
much slower
The sphincter (muscle valve) regulates passage if contents between the small and large intestine (colon)
ileocecal sphincter
Nearly 60 times your body's total water volume is filtered through the kidneys every day. How are we able to avoid dehydration?
Most of the components of plasma that are filtered are reabsorbed
Smooth muscle is present in the walls of....
arteries and veins, but not capillaries
Note
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