Middle piece - structure of the sperm, Biology

Middle piece - Structure of the Sperm

Just behind the head, the small constriction (neck) carries a distal and a proximal centriole. The two lie at right angle to each other. The proximal centriole initiates the cleavage divisions of fertilized egg while the distal centriole provides attachment to axial filament of tail. The middle piece has mitochondria surrounding the base of the axial filament of the flagellum (tail). The mitochondria form compact and isolated clumps throughout the middle piece, or there may be a tightly coiled spiral of mitochondria around the proximal centriole of filament and distal centriole.

The mitochondria carry the oxidative enzymes responsible for oxidative phosphoryIation. Therefore, it is the 'power plant' supplying the energy to the flagellum to be used for propulsion of the sperm through the fluid medium. A dark ring is sometimes seen at the posterior end of the middle piece as a boundary between middle piece and the tail. It is known as 'ring centriole' but electron microscopic study reveals that the ring centriole does not resemble a centriole in its structure. Its origin and function are unknown.

Posted Date: 1/24/2013 6:23:55 AM | Location : United States







Related Discussions:- Middle piece - structure of the sperm, Assignment Help, Ask Question on Middle piece - structure of the sperm, Get Answer, Expert's Help, Middle piece - structure of the sperm Discussions

Write discussion on Middle piece - structure of the sperm
Your posts are moderated
Related Questions
Examine the benefits and risks bird flu research poses to society. Indicate if you believe there are more benefits or more risks associated with this research, and give a rationale

What is the mechanism by which gap junctions could relay signals from G protein coupled receptors between cells within a tissue?

Q Under which environments do echinoderms live? Echinoderms are marine animals and they live in salt water.

Coo k in g loss and quality Yields and cooking losses of products are important as these determine acceptability and economics of products. Higher cooking losses increase th

Define the Skeletal muscle A. Binding of calcium ion to its receptor site on the actin molecule blocks the attachment of the head of the tropomyosin molecule to its binding sit

Amoeboid Protozoan Amoeboid protozoan are distinguished by the presence of flowing extensions of their body known as pseudopodia. These are used for feeding and locomotion. Th

TESTE S (TESTICLES) - 2 in number (Diarchic). Pinkish in colour. Oval shaped. 4-5 cms long, 2.5 cm wide and 3 cm thick. Mesodermal. In embryonic stage attached to kid

Lamellar compaction and remodeling (6 to 18 weeks) A remodeling phase is initiated in which hematopoietic-derived osteoclastic cells form cutting cones will remove the establis

Polyarthritis  1)  Gonococcal - Therapeutic trial of pencillin may help in diagnosis of gonococcal  infection.  2)  Viral infections such as rubella and hepatitis B may have

L YMPH A TI C SYSTEM As 'Middle man' of circulation it mediates exchange between blood and the tissue. It is also a collecting system like venous system. Basically 'o