Complete question:
The endplate potential (EPP) at the frog neuromuscular junction occurs because ACh simultaneously increases the conductance of the postsynaptic membrane to Na and K
Answer:
TRUE
Explanation:
The Acetylcholine neurotransmitter is released from the presynaptic cell by the process of exocytosis.
Once the molecule is in the intercellular space, it moves forward the postsynaptic membrane to join its receptor in the motor plate.
Once the joining has occurred, the receptor acquires a channel shape allowing the ion transference that will make possible the modification of the action potential. Ions traffic will consist of the pass of sodium and calcium to the interior of the cell and potassium to the exterior. Quantitatively, the interchange Na-K is the most significant.
K+ follows a concentration gradient, while Na+ follows an electrochemical gradient. The interchange results in an increase of positive charges in the interior of the muscular cell.
Whenever there is a sufficient number of Acetylcholine receptors are active, the depolarization threshold of the motor endplate is exceeded. This activates an action potential that extends to the rest of the muscle membrane.
<h2>Order of parts of a microscope
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First – ocular lens
Second – Body tube
Third – Revolving Nosepiece
Fourth – Objective lens
Fifth – Coverslip
Explanation:
Ocular lens: The lens present in the eyepiece at the top of the microscope, close to the eyes, through which a person looks through the microscope to view the specimen. Magnification of ocular lens in a compound microscope is usually 10x
Body tube: The tube that connects the eyepiece with the objective of the microscope for continuous optical alignment.
Revolving Nosepiece: The turret that holds the objective and revolves to select the objective lens according to its magnification
Objective lens: The objective lens is located above the specimen rack. Objective lens creates the primary image of the specimen viewed through the eyepiece. A single compound microscope can have more than two objective lens and their magnification ranges from 4x, 10x, 40x, 100x power.
Coverslip: The cover glass which covers the objective lens and prevent from touching the specimen
. This is the object directly above the specimen.
Answer:
The answer is C
Explanation: The random change in the gene pool is due to genetic drift. Remember, genetic drift occurs at a more rapid rate when the population size is reduced. The flood is a random occurrence. It could have as easily been a drought.
