The answer is A because it is basically a guess
Answer:
Euglena are classified into the Kingdom Protista, and the Phylum Euglenophyta.
Explanation:
Answer:
C. tetanic contractions might occur, which would stop the heart's pumping action.
Explanation:
The absolute refractory period of the cardiac muscle action potential refers to the time interval when the voltage gated sodium channels are inactivated. The absolute refractory period lasts ~180 msec. The action potential lasts 200-220 msec.
The refractory period of cardiac muscle is dramatically longer than that of skeletal muscle. This prevents tetanus from occurring and ensures that each contraction is followed by enough time to allow the heart chamber to refill with blood before the next contraction.
In order words, It is important for the cardiac muscle cells to have a longer refractory period, because if they were short like the skeletal muscles, the heart could enter tetanic contraction/summation which is when muscle is stimulated so rapidly that it does not have a chance to relax at all between stimuli.
B. The top image is in test 1, and the bottom image is in step 3.
submitted review and got it right
A single motor neuron together with all the skeletal muscle fibers it innervates is called a motor unit.
- Motor neurons are more than just relays for the motor commands sent down the hierarchy from higher levels. They themselves are parts of intricate circuits that carry out extensive information processing.
- Due to their highly branching, intricate dendritic trees, motor neurons are able to integrate inputs from several other neurons and generate accurate outputs.
- A single motor neuron, and nothing else, innervates each and every muscle fiber (make sure you understand the difference between a muscle and a muscle fiber). However, several muscle fibers can be innervated by a single motor neuron.
- A motor unit is the aggregate of a single motor neuron and all of the muscle fibers that it innervates. The innervation ratio refers to how many fibers a motor unit innervates.
Learn more about the motor unit with the help of the given link:
brainly.com/question/13554533
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