ENDOCRINE ORGANS AND RESPIRATORY SYSTEM
ENDOCRINE ORGANS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Cardiac cells have more receptors for epinephrine than do intestinal cells.
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Epinephrine circulates to the heart first and thus is in higher concentration around cardiac cells.
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The two types of muscle cells have different signal transduction pathways for epinephrine and thus have different cellular responses.
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Cardiac muscle is stronger than intestinal muscle and thus has a stronger response toepinephrine.
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Detailed explanation-1: -protein phosphatase-enzyme that transfers a phosphate group from ATP to a protein, causing a shape change that usually activates that protein. When epinephrine binds to cardiac (heart) muscle cells, it speeds their contraction. When it binds to muscle cells of the small intestine, it inhibits their contraction.
Detailed explanation-2: -So, the correct option is ‘They are connected by intercalated discs, through which action potential spread to all cells in the heart’.
Detailed explanation-3: -Answer: The same hormone can have different effects on muscle cells because the two types of muscle cells have different signal transduction pathways for epiphrine and hence have different cellular responses.
Detailed explanation-4: -Gap junctions within the intercalated disks allow impulses to spread from one cardiac muscle cell to another, allowing sodium, potassium, and calcium ions to flow between adjacent cells, propagating the action potential, and ensuring coordinated contractions.