The structure and function of the ovum in the female reproductive system
The structure of the ovum
The ovum ( the egg cell ) is the female reproductive cell in the female reproductive system , It is large in size ( as sesame seed size ) due the the storage of the nutrient materials .
The ovum is not capable of active movement , and it is much larger than the sperms cells , when the ovum joins with the sperms during the fertilization , and a diploid cell ( the zygote ) is formed , and the embryo is formed , which gradually grows into a new organism .
The ovum is a spherical cell and not mobile ( static ) , It is one of the largest cells in the human body , it is visible to the naked eye without the aid of a microscope or other magnification device , and it is approximately 0.12 mm in diameter .
The ovum consists of the nucleus , the cytoplasm and the cellular membrane ( that surrounds the cell from outside ) , The nucleus contains one half of the genetic materials ( the chromosomes ) , and the cytoplasm stores the food and the nutrients .
The function of the ovum
The ova provide the nutrients for the growing embryo until it sinks into the uterus and the placenta takes over .
The ovum ( egg cell ) in the animals and the plants
The ovary produces the ovum ( the egg cell ) which is the gametes ( sexual reproductive cells ) in the animals and the plants .
The ovum is large in size because it stores the nutrients , it is produced in few numbers and it is not mobile ( static ) , It contains half the number of chromosomes that are found in a female body cells .