Which of the following functions does the myelin sheath perform for a nerve cell?
Insulation
Regeneration
Sensory perception
Nutrition
The Correct Answer is A
The myelin sheath is a protective membrane that wraps around parts of certain nerve cells.
Its fatty-protein coating provides protective insulation for your nerve cell like the plastic insulation covering that encases the wires of an electrical cord ².
This allows the electrical impulses to travel quickly and efficiently between one nerve cell and the next ². The other options are not correct because they do not describe the functions of the myelin sheath.
Regeneration, sensory perception, and nutrition are not functions performed by the myelin sheath for a nerve cell.
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Related Questions
Correct Answer is B
Explanation
The relaxation of the chambers of the heart during the cardiac cycle is called diastole. The cardiac cycle is a sequence of events that occurs when the heart beats ². It consists of two phases: systole, when the heart contracts and pumps blood into circulation, and diastole when the heart relaxes and fills with blood.
The other options are not correct because they do not accurately describe the relaxation of the chambers of the heart during the cardiac cycle. Tachycardia is a rapid heart rate, bradycardia is a slow heart rate, and systole is the contraction of the heart chambers.
Correct Answer is B
Explanation
The structure that is present in both prokaryotic and eukaryotic cells is the cell membrane ². The cell membrane is a thin layer that surrounds the cell and separates its internal environment from the external environment. It is composed of a lipid bilayer and proteins and regulates the movement of substances into and out of the cell.
The other options are not correct because they are not present in both prokaryotic and eukaryotic cells. The endoplasmic reticulum, chloroplast, and Golgi apparatus are organelles that are only found in eukaryotic cells.
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