In fertilization, fertilization occurs within the body of the female

Fertilization of the egg by the sperm takes place in the internal environment. It is the process in which there is union of female egg and male sperm, which takes place at the ampullary-isthmic junction of the Fallopian tube and it ultimately results in the formation of zygote.

During the process of sexual reproduction, when there occurs fertilization of ovum (n, 23 chromosomes) by the sperm (n, 23 chromosomes)  in order to restore the diploid number and creates a zygote (2n, 46 chromosomes) that divides and grow by the process of mitosis in order to form a multi-cellular human.

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

it would affect precipitation by causing flooding in some areas of the world due to climate increasing, causing the glaciers in the northern and southern pole of our planet to melt.

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