Spermatozoan ๐Ÿ‘‡๐Ÿป

 " SPERMATOGOAN "



Definition :- A spermatozoan is a haploid male gamete whose primary function is to fuse with ovum to restore diploidy and to transmit paternal characters to the offsprings.

Structure :- A mammalian sperm is minute, microscopic, flagellated and motile gamete with no nutritive material, protective envelopes and most of cell-organelles like ribosome, endoplasmic reticulum, etc. The whole body of sperm is enveloped by plasma membrane only. It is basically formed of four parts, each performing a specific function

1. Head :- Shape of head varies in different mammals. It is generally oval and flat (in man, bull, rabbit). Basically the head is formed of two parts

Acrosome (Gr. akron extremity; soma=bodybuilder ):-- It is small cap-like pointed structure present at the tip of nucleus. It is formed from a part of Golgi body of spermatid. During the sperm entry, the acrosome secretes a lytic enzyme, called hyaluronidase) which helps in the penetration of ovum.

Nucleus.:-It is generally long, narrow and pointed but is flat and oval in human sperm. It is formed by condensation of nuclear chromatin of spermatid and loss of RNA, nucleolus and acidic proteins. Chemically, the nucleus is formed of deoxyribonucleoprotein (DNA basic proteins). It is the carrier of genetic information.

3. Middle piece.:-- It lies behind the neck and is cylindrical in the human sperm. It is formed of a mitochondrial spiral. nebenkern, around the proximal part of axoneme. The mitochondria are the carriers of the oxidative enzymes and the enzymes which are responsible for oxidative phosphorylation. So the middle piece is the power house of a sperm. Posterior half of nucleus, neck and middle wed by a sheath manchette:


2. Neck. It is the smallest part of spermatozoan and may be indistinct. It is formed of two centrioles perpendicular to each other and is formed from the centrosome of spermatid. Each centriole is a microtubular triplet structure having 9+ 0 arrangement. Proximal centriole lies in a depression in the posterior surface of the nucleus and is perpendicular to main axis of the sperm. Distal centriole is along longitudinal axis of the sperm.

3.Tail :-- It is the longest part of sperm. It is slender and tapering part. It is formed of two parts central, contractile and microtubular part called axoneme or axial filament, and outer protoplasmic sheath. Axoneme is formed of 11 proteinous microtubules arranged in 9+2 manner.
 Sometimes, a ring centriole may be present at the junction of middle piece and
 flagellum. Tail shows lashing movement's
 which provide forward push to the sperm.

( Note):-๐Ÿ‘‡๐Ÿป๐Ÿ‘‡๐Ÿป
!! * There may be an explanation as to the results of other biology results, you can search the website and see.
--๐’œ๐“‚๐’ถ๐“ƒ...
AสŸสŸ แด›สœแด‡ ส™แด‡sแด› ๐Ÿ˜ŠTสœแด€ษดแด‹ า“แดส€ Yแดแดœ ๐Ÿ™๐Ÿป !!


(

Comments

Post a Comment

Popular posts from this blog

Reproductive Technology ✍๐Ÿป

*Reproductive Technology! !  Reproductive technology encompasses various medical techniques to enhance fertility and increase conception chances. Here's a rundown of key terms and technologies: *Types of Reproductive Technologies:* - *IVF (In Vitro Fertilization)*: Fertilizing an egg with sperm outside the body and transferring the embryo into the uterus. - *ICSI (Intracytoplasmic Sperm Injection)*: Injecting a single sperm directly into an egg to overcome fertilization issues. - *ART (Assisted Reproductive Technology)*: Includes IVF, ICSI, and other techniques to assist reproduction. - *IUI (Intrauterine Insemination)*: Placing sperm directly into the uterus to bypass cervical barriers. - *GIFT (Gamete Intra-Fallopian Transfer)*: Transferring eggs and sperm into the fallopian tube for fertilization. - *ZIFT (Zygote Intra-Fallopian Transfer)*: Transferring a fertilized egg into the fallopian tube. - *PGD (Preimplantation Genetic Diagnosis)*: Testing embryos for genetic disorders be...
Read more

Structure of Ovum ๐Ÿ‘‡๐Ÿป

Image
 " STRUCTURE of OVUM " Definition .:--Ovum is a maternal haploid gamete and is primarily concerned with receiving the sperm and is determined to develop into a fully developed multicellular organism after fertilization (syngamy) or without fertilization (parthenogenesis). It is generally with reserve food and is genetically programmed. Structure. An ovum is generally spherical, non-motile gamete with yolky cytoplasm and enclosed in one or more egg envelopes. Size of ovum varies in different animals and depends upon the amount of yolk. Size of ovum varies from 10 ยต to a few cm. The largest sized egg is of ostrich and is about 170 x 135 mm. Egg size and yolk amount are interdependent. It is about 50 ยต in many polychaete worms, 150 ยต in tunicates but very large sized in birds and reptiles. In mammals, it is generally microlecithal and about 100 ฮผ. Human ovum is microlecithal with large amount of cytoplasm. Cytoplasm is differentiated into outer, smaller and transparent exoplasm ...
Read more

What is Bioethics ⁉

Image
 " What is Bioethics ? Certain acts are regulated by communities to consider their legitimacy. Such regulation is called ethics. Bioethics include standards followed by us to regulate the activities linked with biological activities. Unexpected methods are being adopted in the fields of biology like recombinant DNA technology and pharmaceutical studies. Bioethical concerns related to biotechnology are: (i) For the production of pharmaceutical products like proteins many animals are reduced to the status of factory. (ii) Animals undergo great physical sufferings while performing experiments on them. (iii) There is violation of 'integrity of species' due to transferring of a transgene from one species to another. (iv) 'Concept of humanness' is diluted due to introduction of human genes to various animals or vice versa. (v) Biotechnological studies have been considered as mere exploitation of living beings. (vi) Biodiversity may be affected due to biotechnological exp...
Read more