Which of the Following Best Describes the Soma of a Neuron?
- Which of the following best describes the soma of a neuron?
- The part of the neuron that contains the nucleus.
- The part of the neuron that receives a signal from the previous neuron.
- The part of the neuron that transmits a signal to the next neuron.
- The part of the neuron that insulates and protects the axon.
- Which of the following best describe interneurons?
- Detects information from the outside world.
- Sends signals to elicit a response.
- Afferent neurons.
- Form connections between neurons in the CNS, sensory, and motor neurons.
- Which of the following best describes how myelination speeds up the transmission of action potentials?
- Myelination provides insulation, which increase the rate of depolarization.
- Myelination allows for saltatory conduction, or the jumping of an action potential from one node of Ranvier to another.
- Myelination makes the axons have effectively larger diameter, and hence conduct the signal faster.
- Myelination only provides protection and does not increase the speed of transmission.
- Which of the following ions is not important for establishing the membrane potential?
- Sodium (Na+)
- Chloride (Cl-)
- Potassium (K+)
- All of the above are important for establishment of membrane potential.
- Which of the following mechanisms is not a majorcontributor to the resting potential?
- Sodium-Potassium Pump
- Potassium leak channels
- Sodium leak channels
- All of the above are major contributors to the resting potential
- The threshold potential is about -50 mV. What does this mean?
- A cell is unable to achieve a potential of less than -50 mV.
- A cell is unable to achieve a potential of greater than -50 mV.
- Voltage gated Na+ channels don’t open until the membrane potential is -50 mV.
- Voltage gated K+ channels don’t open until the membrane potential is -50 mV.
- After a cell is depolarized, what happens?
- Na+ channels open.
- K+ channels open.
- K+ channels close.
- Two of the above are correct.
- A neurotoxin results in a hyperpolarization of the membrane that is slowly restored to resting potential. What is the most likely action of this neurotransmitter?
- Prevents Na+ channels from opening.
- Prevents Na+ channels from closing.
- Prevents K+ channels from opening.
- Prevents K+ channels from closing.
- Which of the following is false regarding chemical synaptic transmission?
- Utilizes Ca2+ to trigger exocytosis.
- Neurotransmitter binding is an excitatory response, while neurotransmitter failing to bind is an inhibitory response.
- Synaptic signaling ends and neurotransmitters are broken down or reuptake occurs by the presynaptic cell.
- The same neurotransmitter is able to elicit a different response in different situations.
- What does summation refer to?
- Many small excitatory signals can result in an action potential.
- To gain a large response, a larger action potential is signaled for.
- Two neurons may receive the same signal to achieve a large response.
- Motor neurons that work on the same muscle combine together to achieve movement.
- If air is 25% oxygen, and the total pressure is 800 mmHg, what is the partial pressure of oxygen?
- .25 mmHgb. 800 mmHgc. 200 mmHgd. 600 mmHg
- Which of the following is false regarding the lungs?
- The lung’s surfaces are very dry in order to increase gas exchange.
- Alveoli serve to increase the surface area to increase gas exchange.
- There is great blood flow to the lungs to increase gas exchange.
- Each lung is encased by a pleural sac.
- Which of the following best describes how inhalation occurs?
- The diaphragm elevates, which increase pressure in the lungs, and air floods in.
- The diaphragm lowers, which decreases pressure in the lungs, and air floods in.
- The diaphragm elevates, which increases volume in the lungs, and air floods in.
- The diaphragm lowers, which decreases volume in the lungs, and air floods in.
- Which of the following is true regarding oxygen transport?
- Not enough gas can dissolve in blood on its own to support our metabolic needs, so our body utilizes myoglobin to transport a high level of oxygen.
- Oxygen dissolves well in blood and this level of oxygen is enough to support our normal metabolic needs.
- Hemoglobin can covalently bind 4 oxygen molecules to transport to the body.
- Hemoglobin is made up of 4 iron containing subunits.
- Which of the following is a relationship between CO2, H+, and oxygen levels in blood?
- When muscles release more CO2, blood pH rises.
- As pH decreases, hemoglobin releases more oxygen.
- Increased CO2 production by muscles causes hemoglobin to pick up more oxygen.
- Oxygen dissolves in water to form carbonic acid.
- Which of the following is false regarding the oxygen-hemoglobin dissociation curve?
- The sigmoidal curve is a result of cooperative binding.
- Cooperative binding means that it is easier to bind the first oxygen than a second.
- Hemoglobin is very sensitive to slight changes in the partial pressure of oxygen in the range associated with body tissues.
- More oxygen binds to hemoglobin when the partial pressure of oxygen is high.
- Which of the following component of blood is incorrectly matched to its function?
- Platelets – formation of blood clots
- Hormones – transportation of carbon dioxide
- Red blood cells – transportation of oxygen
- White blood cells – maintenance of body’s immune system
- Because the concentration of minerals is higher in roots than in the soil…
- Plants require active transport to uptake minerals or water.
- Water flows into roots via osmosis, but minerals cannot enter the roots.
- Minerals require active transport to enter roots, but water enters via osmosis.
- As water flows into the roots, minerals flow out of the roots into the soil.
- Xylem is chiefly responsible for what?
- Transport of water and minerals.
- Production of sugars.
- Transport of sugars.
- Intake of carbon dioxide from the air.
- Which of the following is false regarding xylem?
- When mature, the cells are dead.
- Contains both tracheid cells and vessel elements.
- Xylem generally transports up a plant (ie. from root to shoot)
- All of the above are true regarding xylem.
- Which of the following is correct regarding stomata?
- Guard cells deflate to open the stomata.
- Light signals the opening of stomata.
- Stomata open and close in order to not uptake too much CO2.
- Stomata open and close in order to not release too much oxygen.
- Which of the following best describes the cohesion-tension theory?
- Although water would tend to evaporate out of the leaves, because of the high level of cohesion, water is actually unable to evaporate at most times.
- As water evaporates from the lower leaves, the upper leaves regain this water, preventing a majority of water loss.
- Plants use active transport to move water up the plant through the xylem to replace the water that evaporates from leaves.
- Although water evaporates from leaves, because of water’s high level of cohesion, this pulls water up the plant from the roots to replace the water lost.
- Which of the following is not a component of phloem?
- Sieve-tube elements
- Companion cells
- Sieve plates
- Vessel elements
- Which of the following is false regarding phloem sap translocation?
- Transport goes from the source to the sink.
- It is driven by differences in H2O pressure and osmosis.
- The movement of sugars requires the usage of ATP.
- Long distance transport takes place in sieve-tube elements.
- Which is not a way that nutrients are absorbed by the alimentary canal?
- Active transport
- Facilitated diffusion
- Through plasmodesmata
- Passive transport
- Which of these is not an accessory organ of the digestive system?
- Tongue
- Gallbladder
- Kidneys
- Stomach
- What are the components of gastric juice?
- H+ and Cl-
- Pepsinogen
- HCl and pepsinogen
- Parietal and chief cells
- Which of the enzymes is incorrectly matched with its substrate?
- Pepsin proteins
- Trypsin lipids
- Lipase lipids
- Amylase carbohydrates
- What two structures absorb nutrients in the small intestine?
- Lymphatic vessel and alveoli
- Alveoli and capillaries
- Capillaries and lacteal
- Veins and arteries
- What structures increase the surface area of the small intestine?
- Villi
- Capillaries
- Alveoli
- Microvilli