Difference between Sperm and Ovum

Sperm and ovum are the biological structures needed for generation after generation. Males produce sperms, and females produce sperms. During copulation, sperm is deposited in the female genital tract. Then, the sperm and ovum fertilize together to form a zygote, the vital link between one generation.

Sperms – A Descriptive View

Mostly, there are two types of gametes produced for reproduction in all species. Sperms are produced in male genital organs, and ovum or egg is produced in the female body. Both the gametes are highly motile, and their fusion leads to a phenomenon known as fertilization. Sperms are small as compared to an ovum.

Sperms have a stripped-down appearance. They possess a flagellum to easily travel through the aqueous medium without being disturbed by other cell organelles such as Ribosomes, Endoplasmic Reticulum, Golgi Bodies, etc. However, they are responsible for carrying the DNA to the cell. They have many mitochondria present in them that provide energy to the flagellum to travel easily and fast. Typically, a sperm is divided into three parts:

1. Head
2. Neck
3. Tail

Typically, a sperm has two distinctive parts that differ morphologically and functionally. The tail of the sperm is covered by a single plasma membrane, and its head has a haploid nucleus which is highly condensed.

The nucleus has a tightly packed DNA that helps the nucleus to have a tight volume for the easy transportation of the sperms.

As sperms are produced in billions during each ejaculation, sperms are highly competitive. In addition, not all sperms can fertilize an ovum because inside the female genital tract, sperms experience phagocytosis.

Sperms also have highly charged proteins present inside them, known as protamines.

Structure of sperms

The structure of the sperm, when viewed longitudinally, has a head, midpiece, and tail. In addition, the head of the sperm has an acrosome and a secretory vesicle known as the ‘Acrosomal Vesicle.’

As the sperms need to penetrate inside the egg, it needs some enzymes to hydrolyze the outer membrane of the ovum.

The hydrolytic enzymes help the sperm to get inside the ovum by breaking its membrane. When the sperms travel through the female genital tract and reach the egg, the vesicle releases its hydrolytic enzymes by a process known as exocytosis. This phenomenon is known as an acrosomal reaction.

The tail of the sperm is made up of a long flagellum. It has a central axoneme present in it.

9+2 organisation of the axoneme is observed in the flagellum of most of the sperms.

The 9+2 arrangement in the axoneme means that two single microtubules are surrounded by nine doublet microtubules. The mitochondria are present in the midpiece, which provides ATP to the sperms. 

Ovum – A descriptive view

The females produce gametes known as ova for the continuation of life. Ovum is a single egg, and ova are the plural form of eggs. The primitive germ cells give rise to an ovum. These germ cells are found to be deeply seated in the layers of the ovaries. Repeated divisions form small cells known as oogonia, and ovum is formed from oogonia.

The size of the ovum varies. Typically, a very small human egg measures about 0.2 mm in size and lies within the egg follicles inside the ovaries.

The cytoplasm of the ovum is known as yolk or ooplasm. The nucleus is called a germinal blister, and the nucleolus is called a germinal spot.

The ovum is surrounded by a thick layer known as Zona Pellucida, and it is transparent. Zona Pellucida protects the ovum from damage and also by the attack of the sperms when they come in contact with the egg. When a sperm and an egg are released simultaneously and fuse, it leads to fertilization.

Every female is born with a limited number of eggs since its birth. Therefore, after a certain age, the production of the eggs stops, and the female reaches a stage known as ‘Menopause. ‘

Difference between sperm and ovum

1. Sperms are the gametes that are produced in the body of a male. Ovum or ova are the gametes produced in the body of a female.
2. The formation of sperms is known as spermatogenesis, and the formation of the ovum is known as oogenesis.
3. Sperms are smaller in size as compared to an ovum. Both the sperms and ova can move and are said to motile.
4.   Sperms have mitochondria that are present inside their middle piece. The mitochondria are present all over scattered in the ovum.
5. A small amount of cytoplasm is found in sperms, and a large amount of cytoplasm is found in the ovum.
6. Sperms are produced throughout the life of a healthy male, but the production of the ovum ceases at a certain age. This phenomenon is known as ‘Menopause.’
7. Males remain fertile throughout their life due to the continuous production of sperms. However, female fertility declines at a certain age due to the non-production of the eggs.

Conclusion

Both ovum and sperm are the gametes produced in either of the sexes. They are responsible for the continuation of generations.

They are structurally different and are responsible for a person’s reproductive health.

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