The structure of the sperm in the male reproductive system
The testes of the adult human male produce about 2 billions sperms per day , the life time of a single sperm inside the female vagina ranges from 2 to 6 hours , this period can extend to reach up to 3 days if the sperm managed to break through the cervix and enters the uterus , where it feeds an uterine secretions .
The male reproductive syatem produce , maintain and transport the sperm ( the male reproductive cells ) and the protective fluid ( semen ) , Men who have fewer than 20 million sperm per milliliter of semen may be at risk for having infertility issues .
Only one sperm fertilizes the ovum and achieve a pregnancy , The average ejaculation contains close to 100 million sperm according to the World Health Organization .
The structure of the sperm
The sperm is considered very small if it is compared with the ovum , it is mobile , and it consists of the head , the midpiece and the tail , The tail is thin and long , and it is responsible for the movement of the sperm till reaches the ovum .
The head contains one half of the genetic material ( the chromosomes ) , and the midpiece contains the mitochondria which responsible for energy production needed for the sperms movement .
The reproductive cells in humans and plants
The testis is the reproductive organ in the animals which produce the sperms while the anther is the reproductive organ in the plants which produce the pollen grains .
The gametes in the humans and the plants are small in size , and they are produced in large numbers , The sperms and the pollen grains contain half the number of chromosomes that are found in a male body cells .