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Monthly Archives: May 2012

Human Fertilization

Fertilization is the key to biological reproduction. In humans, sperm cells in males and egg cells in females are the reproductive cells. Each reproductive cell contains 23 thread like structures called chromosomes which carry the traits or characteristics from the parents to offspring.

 Egg cell with sperms

The sperm is composed of the head and the tail. the head contains 23 chromosomes. The tail is a whip-like structure that enables the sperm to swim to where the egg cell is. On the other hand, the egg cell is a round structure that contains the nucleus inside and is covered with membrane. The nucleus contains the female chromosomes.

When a single sperm enters the ovum, the process is known as fertilization. This fertilization must occur while the egg cell or ovum is still in the fallopian tube.

The successful sperm initially binds to the outer layer of the ovum through the hook-like structure called a receptor on its surface. Different species of animals have different matching receptors. This is why fertilization is only possible between a male and a female of the same species.

The egg cell is now called a zygote. It immediately begins to multiply by normal cell division and multiple duplication or replication. Cell division and replication continue until a hollow ball, called a morula, is formed. This morula moves from the Fallopian tube into the uterus and implants itself on the uterus lining. Then embryonic development starts.

Cell Division

Morula

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Posted by on May 29, 2012 in Uncategorized

 

Make it up…

The word I will make it up to… to some extent is not understood by some.

We cannot make it up from the lost time that we have missed. Simply saying sorry will make it worst.

The best thing to do is Get on your feet and do something now…

Make it better so it feel better. Sometimes, what we tend to do is to make up for the lost. And when it happens again the result end will begin to what had happened before. Such an idiot to recall what makes a ring circle.

If that will be the case, the loss will always be remember. As if you never tried at all. Irony.

You cannot make up for what is being done. It is already done. The time element cannot be returned then expected that everything is fine.

The good thing is you can beat the lost time. Quality is what we expect from the lost time.

Not tomorrow, not until, but now.

So don’t make it up. Do what is now. For tomorrow and until…

 

 
3 Comments

Posted by on May 29, 2012 in Uncategorized