Structure & Function Of Secondary Oocyte

-

                                        Oocyte Structure




The egg or ovum is large in size as compared to the male sperm. It is non-motile and contains food in the form of yolk, glycogen, and protein. The ovum is composed of the following parts -

Plasmalemma

Primary membranes

Secondary membranes. 


  • Plasmalemma - It is the outer layer of the egg made up of lipoprotein. It is also known as the plasma membrane. This layer is 110 angstrom in thickness.

  • Primary membranes - In certain reptiles and coelenterate another egg membrane is also presently known as a primary or secondary membrane. It is secreted around the plasma membrane by the follicle cells of the ovary itself. In birds, molluscs, insects, this membrane is called by vitelline membrane while in mammals it is known as Zona pellucida. This vitelline membrane is made up of fibrous protein and mucoproteins. The plasma membrane and vitelline membrane are separated by some space known as Perivitelline space.

  • Secondary Membrane - The primary egg membrane is surrounded by another membrane for the protection of the embryo known as Secondary membrane. This membrane is secreted by oviduct and some reproductive organs of the body.  In amphibians, it gives jelly-like appearance while in reptiles, and in birds, the egg membrane and shell are secondary membrane. 

Related Links  - 

Comments

Post a Comment

Popular posts from this blog

Sycon Canal System With Diagram & Significance | Biology Blog

-
Image
                                     Canal system in Sycon  A sea creature called a sycon, or scypha , is usually found clinging to rocks or other surfaces. These creatures have tube-shaped bodies that open outward with the help of a hole called an Osculum . They have tiny openings called Spiracles and Ostia all over their bodies to let water in. This water flows through canals inside their bodies and comes out through the Osculum, which is a larger opening used for breathing. We'll observe the shape of this canal system, why it is essential for those animals, type of canal system , and  its significance. The Sycon Type Canal system is the unique feature of the phylum Porifera . This system is also known as the  aquiferous canal system . This system supports the significant function of the body like nutrition, respiration, excretion, etc. History Overview -  Grant, a scientist from Scotland, spent a lot of time studying sponges. He was one of the first to really explain how t
Read more

Aurelia Aurita Life Cycle: Characterstics, Classification

-
Image
                                             Aurelia  Aurelia aurita is a type of zooplankton found all over the world. They are see-through and don't have eyes, brains, or hearts. They're usually between 2 to 15 inches wide. Even though they prefer being alone, they get carried together in groups called Blooms by wind and water currents. At night, they look like they're moving through the water like jellyfish, which is why they're sometimes called " jellyfish ".  They have four reproductive organs surrounded by tentacles in their top part. Their body color changes based on what they eat, so they can be blue, pink, or other colors. Let's learn more about Aurelia in detail. Details Of Aurelia Diagram -  Body : The center of the diagram would display the jellyfish's bell-shaped body, often called the " umbrella. " Tentacles : Below the bell, you'd see long, hair-like tentacles extending outward. Oral Arms : The oral arms are  used for
Read more

Types of Eggs of Animals in Zoology (Embryology ) | Biology Blog

-
Image
                                             Types of Egg Hello guys! We'll examine a crucial area of zoology in this blog: different varieties of eggs. So let's define reproduction first before moving on to the subject. Reproduction is the biological process in which a parent is responsible to produce their offsprings which may be of their own kind. Reproduction is a must process for every individual for the continuing existence of the species. As we all know, there are many different species on the planet, and each of them has a unique method of egg production and inside the egg they contain yolk . The yolk is composed of proteins, fats, vitamins, and minerals, which are vital for the growth and development of the embryo.  Eggs can be classified into different types based on the amount of yolk they contain. l.  On the basis of the amount of Yolk - Depending on the quantity of yolks, eggs can be  Alecithal / Microlecithal / oligolecithal - The amount of yolk pr
Read more