Real-Life Lessons About Events Of Fertilization 2021

Real-Life Lessons About Events Of Fertilization 2021

1 Content Of fertilization

  • Encounter of spermatozoa and ova.
  • Capacitation and contact.
  • Acrosome reaction and penetration.
  • Activation of the ovum.
  • Migration of pronuclei and amphimixis.

DEFINITION OF FERTILIZATION

”1Fertilization is the process in which fusion of male and female gametes”.

”Bring male and female together produce a diploid zygote.”

SIGNIFICANCE OF FERTILIZATION

It also activates the egg, which triggers fetal development

Fertilization in mammals occurs in the oviduct.

The ova is viable for approximately 24 hours after ovulation.

TYPES OF FERTILIZATION

1.EXTERNAL FERTILIZATION

Occurs outside of the body of a female

External Fertilization occurs only in water.

Gametes should be discharged at the same time and they should be in close proximity.

In it, the chance of fertilization of gametes is less.

There is no organ for the storage of sperms and eggs present usually.

It occurs both in water and land.

Gametes are discharged at the same time and in close proximity.

In it, chances of fusion of gametes are more.

Certain organs for gametes storage are found.

Different hormones come into action e.g; during ovulation.

Eggs are produced in less quantity.

It is of advanced type and is superior biologically.

Increased number of the egg produce insure the species.

For example.

Fish and Amphibians.

2.INTERNAL FERTILIZATION

Occurs inside the body of the female.

Fewer numbers of eggs are produced.

Increased parental care insures species survival.

It occurs both in water and land.

Gametes are discharged at the same time and in close proximity.

In it, chances of fusion of gametes are more.

Certain organs for gametes storage are found.

Different hormones come into action e.g; during ovulation.

Eggs are produced in less quantity.

It is of advanced type and is superior biologically.

1.Encounter of spermatozoa and ova

A major issue is that sexual reproduction combines with spermatozoa or ova in a fluid medium in the same surface.

so individual sperm may reach the surface of the ova at the right time.

previously it was thought that sperms are attracted towards the ripe egg by chemotaxis.

The female sea urchin Campanularia is found in the egg cortex. Fish etc. are responsible for the maturation of eggs

2.Capacitation and contact

3.The change in the spermatozoa that enables the egg to fertilize is called capacitation.

The phenomenon of capacitation relates to the capacity of spermatozoa to fertilize eggs of the same species but not of other species.

Frank Lillie was the first to show that a chemical substance is discharged by a newly laid sea urchin egg.

This substance diffuses into the seawater and causes sperm cells in the neighborhood to become more active and attracted to the cell

This condition is called chemotaxis, which indicates that the sperm was responding to the chemical. This substance is found in the jelly that surrounds the eggs.

3.Acrosome reaction and penetration

Eggs are wrapped in one or more egg membranes or gelatin layers or follicle sealers, outside the plasma membrane.

These layers form barriers to penetration through the spermatozoa and work to prevent fertilization by sperm from multiple spermatozoa or other species.

Certain enzymatic proteins called sperm lysins are produced presumably by the sperm acrosome  Sperm licenses vary from one group of animals to another.

N some cases the dissolution of the egg envelopes may be brought about by a simpler means. that the jellycoat of echinoderm eggs carbon dioxide produced by the spermatozoa in the course of their respiration.

In mammals, the egg is encased in a layer of follicular cells, called corona radiate. These cells are held together by an adhesive cementing substance called hyaluronic acids, mucopolysaccharides.

Sperm acrosomes are formed by an enzyme, hyaluronidase, which acts to dissolve the adhesive and disperse the cells of the corona radiate.

In mammals, the eggs are encased in a layer of follicular cells, called corona radiata.

These cells are combined with an adhesive cementing substance called hyaluronic acid, a mucopolysaccharide.

Then penetrate to reach the plasma membrane of the egg.

4.Agglutination

This adhesion of spermatozoa to the surface of the egg its literal side and even to each other results in their clumping or agglutination.

Due to this agglutination of spermatozoa was studied by Lillie (1919). He observed that fertilization and antifertilizin occur in the egg and sperms respectively.

The main source of fertilizer is the egg and it is located in the plasma membrane.

The fertilizin is a gel formed by glycoproteins or mucopolysaccharide

The surface layer of the cytoplasm of spermatozoa consists of another species-specific acid protein is known as antifertilizin.

The remarkable peculiarity of the fertilizin and antifertilizin of the same species.

5.MECHANISM OF FERTILIZATION

Gametes.

Male gametes is known as sperm, so it is formed with ahead.

Enzyme

The female gametes are known as ovum and they contained yolk, cytoplasm, nucleus but don’t contain centriole. secondary oocytes, covered by proteins layers. zona pellucida around zona p\euccida there is corona radiata.

Arivel of the sperm

During copulation male body releases semen through the penis into vegina of the female called insemination. During one time of copulation of sperm. It occurs in the female genital system. Generally, sperm are able to factilize for stying 5-6 hours in the female genital tract.

Although the sperm is fully mature when it is inseminated into the vegina but it still can’t fertilize the ovum.

To fertilize the ovum it has to undergo.

Capacitation.

Sperm gets ejaculated with a layer of glycoproteins seminal proteins on the acrosomal head.

These get washed away when sperm comes into contact with the uterine fluid.

Permeability changes more amount of calcium in the cytoplasm.

Generally, sperm are able to fertilize after staying 5-6hours in the female genital tract.

Removal of membrane cholesterol glycoproteins that help to work the membrane cover.

Dilution of decapitation factor.

Visit

Contact of ovum factor.

After arjaculation, sperms travel  to the urerusand reach to the follobian tube within 30-60 mintues.

It is facilitated; the antperstaltic contraction of uterine muscles and also facilated by prostaglandin present in male seminal fluid.

Sperm and ovum met to each other act as a ambula of the follpain tube.

Although the sperm is fully mature when it is inseminated into the vegina but it still can’t fertilize the ovum.

To fertilize the ovum it has to undergo.

4.Capacitation.

Sperm gets ejaculated with a layer of glycoproteins seminal proteins on the acrosomal head.

These get washed away when sperm comes into contact with the uterine fluid.

Permeability changes more amount of calcium in the cytoplasm.

Generally, sperm are able to fertilize after staying 5-6hours in the female genital tract.

Removal of membrane cholesterol glycoproteins that help to work the membrane cover.

Dilution of decapitation factor.

5.Contact of ovum factor

After ejaculation, sperms travel to the uterus and reach the fallopian tube within 30-60 minutes.

It is facilitated; the antiperistaltic contraction of uterine muscles and is also facilitated by prostaglandin present in male seminal fluid.

Sperm and ovum met to each other act as an ambula of the fallopian tube.

Acrosomes reactions.

During capacitation of the enzyme acrosome release from the acrosomal cap. And release sperm lysins

There are some sperms receptors which are one type of glycoprotein is called ZP3 layers

With the influence of proteolytic enzyme and acrozone the sperm enters the zona Pellucidar

Then it crosses over the perivitelline space and the plasma membrane of the ovum it reaches into the cytoplasm of the forum or the nucleus of the sperm enters into the cytoplasm of the ovum

Cortical and zona reactions

Sperms head in contact with the facilitation cone cause opening of rhodium channels to cause depolarization of ovum membrane

Contact of acrosome stimulates the development of an outgrowth.

Acrosomes release ovum the acrosomes release sperm lysins which helps to learn zone Pellucidar.

Fast block to test boy sperm to other ovum depolarized due to Na(f2)channel.

As sperm get attached to the ovum, endoblast and endoplasmic reticulum to releases ca(F3)IONS within the cytoplasm ovum, they push the particles granules into the perivitelline space.

Granules brust and male ovum less zenopondia to a different sperm and harder.

Penetrating movement of sperms is enable by a protein called Casper present within the tail portion of the sperm that it’s a tunnel-shaped protein formed the ions channel entry calcium into the gamete.

Lilley’s theory of fertilization.

Fertilizin (on zona pellucida) and antifertilizin (on sperm surface).

Washer theory.

Zona pellucida is made of glycoproteins, there are several layers of glycoproteins from which the sperm recognizes ZP3 (is known as sperm receptor).

Cortical and zona reactions

When more than one sperm enters the egg.

This type of zygote does not undergo the development of degenerates.

Cause opening of sodium channel to cause depolarization of ovum membrane.

As sperm get attached to the ovum release ca(2f) inside the ovum they push cortical granules into perivitelline space.

Granules burst and make the ovum less responsive to other sperm harder.

UNION OF OVUM AND SPERM NUCLEUS.

Sperm enter the cytoplasm of the ovum breaks metaphase promoting follicles.

Second polar body expelled.

The nucleus of the body mature ovum become female pronucleus with 2,3 chromosome including autosomes and unisex chromosomes or x-chromosomes.

Simultaneously, the head of the sperm swells and becomes a male pronucleus.

Then2,3 chromosomes of the ovum arrange themselves to reform the 2,3 pairs of chromosomes in the fertilized ovum.

In which process chromosomes of the sperm and ovum reform called karyogamy and fertilized ovum is with diploid nucleus 3 zygote…

admin

Enjoy the little things in life. For one day, you may look back and realize they were the big things. Many of life's failures are people who did not realize how close they were to success when they gave up

7 thoughts on “Real-Life Lessons About Events Of Fertilization 2021

  1. I learned more new stuff on this fat loss issue. Just one issue is that good nutrition is extremely vital whenever dieting. A big reduction in fast foods, sugary foods, fried foods, sweet foods, beef, and whitened flour products may be necessary. Keeping wastes bloodsuckers, and wastes may prevent ambitions for fat loss. While specified drugs momentarily solve the problem, the bad side effects usually are not worth it, and in addition they never present more than a short-term solution. It is just a known idea that 95 of dietary fads fail. Thanks for sharing your opinions on this blog site.

  2. Good day! I know this is kinda off topic nevertheless I’d figured I’d ask. Would you be interested in trading links or maybe guest writing a blog post or vice-versa? My site discusses a lot of the same topics as yours and I believe we could greatly benefit from each other. If you are interested feel free to shoot me an e-mail. I look forward to hearing from you! Excellent blog by the way!

  3. It’s perfect time to make some plans for the future and it’s time to be happy. I have read this post and if I could I wish to suggest you some interesting things or advice. Maybe you can write next articles referring to this article. I wish to read even more things about it!

  4. Wow, superb weblog structure! How lengthy have you been blogging for? you make running a blog look easy. The overall look of your website is wonderful, let alone the content material!

  5. Does your site have a contact page? I’m having trouble locating it but, I’d like to send you an e-mail. I’ve got some recommendations for your blog you might be interested in hearing. Either way, great site and I look forward to seeing it improve over time.

Leave a Reply

Your email address will not be published.