The nerve impulses always travel in one direction from dendrites to axon terminals. What prevents an action potential from travelling backward?
Select one:
a. After repolarization, the refractory period occurs, where the sodium ions are found outside the cell.
b. The refractory period prevents another action potential by lowering the threhold potential.
c. After repolarization, the reversal of ions prevents another action potential as there would not be enough sodium ions outside the cell to rush in.
d. Hyperpolarization of the neuron makes the membrane more positive and prevents another action potential.
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Which of the following rows correctly completes the following statement about synaptic transmission?
The neurotransmitters contained in vesicles enter the synaptic cleft via __A______ to attach to receptor proteins in the postsynaptic membrane. Once the postsynaptic neuron has been stimulated, the neurotransmitters return via ____B_____.
Select one:
a.
A B
Binding Exocytosis
b.
A B
Endocytosis Enzymatic breakdown
c.
A B
Exocytosis Endocytosis
d.
A B
Exocytosis Binding
Question 35
Question text
Diisopropyl fluorophosphate is an insecticide that works by binding with cholinesterase enzyme.
Which of the following statements does NOT describe the function of diisopropyl fluorophosphate correctly?
Select one:
a. It blocks the acetylcholine receptor in the postsynaptic membrane.
b. It causes acetylcholine to accumulate in the synapse.
c. It causes acetylcholine to continuously contract the diaphragm or heart muscle, which leads to death.
d. It causes muscle fatigue and paralysis to occur as muscle contraction cannot be suppressed.
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Question 1. Match the labelled synapse structure with the correct structure or function. Place the correct number in each blank. Use each answer only once.
receptor site for the neurotransmitter (dendrite)
neurotransmitter released by exocytosis from a vesicle
neurotransmitter; the chemical messenger
acetylcholinesterase; an enzyme that breaks down ACh (Acetylcholine)
synaptic vesicle containing the neurotransmitter ACh (Acetylcholine)
axon terminal; the axon knob
synpatic cleft; the synapse; a gap
postsynaptic membrane; of the dendrite; "after" the synapse
presynaptic membrane; of the axon; "before" the synapse
mitochondria; supply ATP for synthesis of transmitters
1.
Structure B
2.
Structure A
3.
Structure E
4.
Structure C
5.
Structure H
6.
Structure J
7.
Structure G
8.
Structure D
9.
Structure F
10.
Structure I
i attached the first picture for matching, the second picture is there to help to solve question 1
i had done question 2, but im stuck on the matching i will put down what i matched and tell me if im wrong and give me the right matching for it because i haven't done 2 of them which is parietal lobe and temporal lobe i cant match them.
Question 2.
5. cerebrum
6. frontal lobe
4. medulla oblongata
7. cerebellum
10.corpus callosum
8.thalamus
3. occipital lobe
parietal lobe
temporal lobe
9.hypothalamus
1.
relay centre; directs impulses from the senses to the correct brain region
2.
of the cerebrum; auditory interpretation; impulses are from the organ Corti
3.
of the cerebrum; visual interpretation; impulses are from rods and cones
4.
involuntary control of heart rate, breathing rate, blood pressure, and swallowing
5.
conscious control; thinking, creative thought, emotions, interpretation of sense receptor impulses (eyes, ears, skin)
6.
of the cerebrum; conscious thought; intelligence, memory, personality; controls voluntary motor-muscle action (such as to throw a ball)
7.
unconscious control of muscle co-ordination and balance
8.
sends messages from one cerebral hemisphere to the other; connects right and left hemispheres
9.
direct link to the pituitary gland of the endocrine system; has a major role in homeostasis regulating HR, BR, temperature, and drives (hunger, thirst, rage, and sexual desires)
10.
of the cerebrum; taste; sense receptors from the body/skin are interpreted (such as Tabasco sauce on the lips)
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Answer
Click to Reveal
thanks a lot 
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Euro-skeptics
a. reject democracy.
b. reject capitalism.
c. reject the European social model.
d. tend to oppose more European integration.
e. worry about globalization.
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2. Schwann cells are a type of glial cell found in the nervous system. In addition to the conduction of nerve impulses, the outermost layer called neurilemma aids in nerve development and regeneration.
After examining the image below, can you explain why brain cells have limited capacity for regeneration?
Cross Section of Human Brain
Human Brain Cross Section. Rajalakshmi L Nair et al.
Select one:
a. Neurons in the central nervous system lack neurilemma of Schwann cells.
b. Neurons in the central nervous system are surrounded by white matter.
c. Neurons in the peripheral nervous system are surrounded by grey matter.
d. Axons of the peripheral nervous system lack neurilemma of Schwann cells.
8.
Match each structure in the reflex arc numbered above with its description given below.
Structure: Answer Answer Answer Answer
Description:
Dendrite of a
motor neuron
Axon terminal of
a motor neuron
Dendrite of a
sensory neuron
Axon terminal of
a sensory neuron
22. Both potassium and sodium channels located along the nerve membrane are voltage-gated. This means that they respond to the changes in the voltage by opening and closing the gates to allow the ions to flow in or out of the membrane.
When the threshold level is reached and depolarization occurs, how come only the sodium ions begin to rush in?
Select one:
a. The threshold level for the potassium channels is lower than the sodium channels.
b. The threshold levels for both sodium and potassium channels are equal, but sodium channels are slower to open.
c. The threshold level for the potassium channels is higher than the sodium channels.
d. The threshold levels for both sodium and potassium channels are equal, but potassium channels take longer to open.
23.During an action potential, the inside of the cell membrane becomes more positive than the outside. Why does this happen?
Select one:
a. During depolarization, the sodium ions rush in and the potassium ions have not begun rushing out, making the outside more positive.
b. During depolarization, the sodium ions rush in and the potassium ions have begun rushing out, making the outside more positive.
c. During depolarization, the potassium ions rush in and the sodium ions have begun rushing out, making the inside more positive.
d. During depolarization, the sodium ions rush in and the potassium ions have not begun rushing out, making the inside more positive.
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Sodium ions move out of the axon because of
a. the opening of sodium channels.
b. the opening of voltage-gated channels.
c. kinesin.
d. electrostatic pressure.
e. the sodium-potassium transporter.
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Nerve impulses travel along the neurons by the opening of channels that allow sodium ions to flow inward, followed by an outward flow of potassium ions. In order to ensure that the impulse may be produced at any time, sodium is actively transported out of the cell, and potassium is transported into the cell by the sodium/potassium pump. Which of the following types of work is performed by the sodium/potassium pump?
A) mechanical
B) electrical
C) concentration
D) synthetic
E) bioluminescent
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Explain the role sodium ions play in the depolarization stage of the action potential.
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Which statement describes slow depolarization?
A) Allows dehydrated sodium ions to enter the negatively charged axoplasm causing the threshold for firing threshold
B) Allows release of the sodium ions from the receptor sites in the ion channels allowing negative ions to enter the axoplasm
C) Occurs until the axoplasm has depolarized 15 to 20 mV to reach -50 to -55 mV, which is the firing threshold
D) Occurs until the calcium ions rebind with the receptor sites to reach firing threshold at -50 to -55 mV
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Which component is not existing in the normal polarized epithelial cells surface or basal membrane?
A:Laminin
B:tight junction
C:lamin
D:integrin
E:cadherin
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Answer
Click to Reveal
Quick question for you
In option C, did you write lamin correctly?
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