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Structure of Sperm MCQ - Practice Questions with Answers

Edited By admin | Updated on Sep 18, 2023 18:34 AM | #NEET

Quick Facts

Structure of Sperm is considered one of the most asked concept.
16 Questions around this concept.

Solve by difficulty

EASY

Which one of the following is not the function of placenta ? It:

secretes oxytocin during parturition.

facilitates supply of oxygen and nutrients to embryo.

secretes estrogen.

facilitates removal of carbon dioxide and waste material from embryo.

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Concepts Covered - 1

Structure of Sperm

It is a microscopic structure composed of a head, neck, a middle piece and a tail.
Head:
- The sperm head consists of mainly the nucleus and acrosome.
- The genetic function is embodied in the sperm nucleus which consists almost entirely of DNA plus nuclear proteins and thus is responsible for the transmission of hereditary characters from the male.
- At the anterior end of the sperm nucleus, occurs a cap-like structure called the acrosome.
- A large number of enzymes especially hydrolases are also present in the acrosome.
- It also contains two most important enzymes such as hyaluronidase and zona Lysin or acrosin which functions during sperm entry into the ovum.
Neck:
- The neck is a short, slightly constricted segment made up of projections located between the base of the head and the mitochondrial helix of the middle piece.
- The two Centrioles lie at right angles to each other are proximal and distal Centriole.
- The distal Centriole forms and gives attachment to the axial filament of the sperm tail; the proximal Centriole has no active function in the spermatozoon but is a potential activist within an egg during first cleavage division of the fertilized egg.
Middle piece:
- Anatomically, the mitochondrial sheath and the outer ring of coarse fibres characterize the mammalian sperm midpiece.
- It is that part of the flagellum which lies between the neck and annulus and forms the most important site for various metabolic activities of the sperm.
Tail:
- It is several times longer than the head.
- It is made up of axial filament surrounded by a thin layer of cytoplasm.
- The end-piece is made up of naked axial filament.
- It provides motility to the sperm.