Sperm typically contain three major membrane bound organelles - a nucleus, mitochondria, and acrosome. The nucleus and the acrosome are found within the head of the sperm, while the mitochondria are found in the midpiece. Why does it make sense to have these membrane-bound organelles located where they are? Select any correct answer that applies.
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a
It makes sense to have the mitochondria located in the midpiece since they are then in close proximity to the flagellar motor. ATP synthesized in the mitochondria are then readily available to the motor when needed.
b
The acrosome and nucleus are located next to each other since the acrosome is derived from the nucleus.
c
Acrosomes contain hydrolytic enzymes; therefore, it makes sense to keep the acrosome as far from the mitochondria as possible, so that no hydrolytic enzymes can attack the mitochondria.
d
The acrosome and nucleus need to be at the head of the sperm in order to carry out their eventual functions. The acrosome will fuse with the plasma membrane of the sperm to release digestive enzymes ahead of the sperm. (the acrosome reaction), and the nucleus needs to be in the head so that it can eventually be transferred easily to the egg cell after membrane fusion.
a
It makes sense to have the mitochondria located in the midpiece since they are then in close proximity to the flagellar motor. ATP synthesized in the mitochondria are then readily available to the motor when needed.
d
The acrosome and nucleus need to be at the head of the sperm in order to carry out their eventual functions. The acrosome will fuse with the plasma membrane of the sperm to release digestive enzymes ahead of the sperm (the acrosome reaction), and the nucleus needs to be in the head so that it can eventually be transferred easily to the egg cell after membrane fusion.
a
It makes sense to have the mitochondria located in the midpiece since they are then in close proximity to the flagellar motor. ATP synthesized in the mitochondria are then readily available to the motor when needed.
d
The acrosome and nucleus need to be at the head of the sperm in order to carry out their eventual functions. The acrosome will fuse with the plasma membrane of the sperm to release digestive enzymes ahead of the sperm (the acrosome reaction), and the nucleus needs to be in the head so that it can eventually be transferred easily to the egg cell after membrane fusion.
The correct answers are a and d.
a) It makes sense to have the mitochondria located in the midpiece since they are then in close proximity to the flagellar motor. ATP synthesized in the mitochondria is readily available to the motor when needed. The flagellar motor is responsible for the movement of the sperm's tail, and by placing the mitochondria near it, energy production and utilization are optimized for efficient motility.
d) The acrosome and nucleus need to be at the head of the sperm in order to carry out their eventual functions. The acrosome will fuse with the plasma membrane of the sperm to release digestive enzymes ahead of the sperm (the acrosome reaction). This allows the sperm to penetrate the protective layer surrounding the egg. The nucleus needs to be in the head so that it can eventually be transferred easily to the egg cell after membrane fusion, facilitating fertilization.
Understanding the functions and locations of these membrane-bound organelles in sperm helps explain the physiological mechanisms involved in successful fertilization.