Answer:
2%
Explanation:
The scientist believe that around 2% of the species that existed on Earth have been preserved in the fossil records. It is still a hot debate about it though, as there are only around 250,000 species identified in the fossil records so far, which is less than a quarter from the species that live in the present.
The reason why scientists believe that the majority of the species have not been preserved are very logical though. One of the reasons is that lot of species existed very long time ago, so their remains just didn't lasted so long. Other reason is the movement of the plates, where we have situation where plates that existed in the past have been totally suducted and melted in the mantle, while others are at the verge of it, so every fossil with them is melted and destroyed too. Another reason is that lot of species do not have hard parts, solid bone structure, so their preservation has been pretty much impossible,
Pancreas.
It produces amylase, protease, lipase (digestive enzymes) and secretes insulin and glucagon (sugar regulation hormones).
The answer is option A.
The gonads of the male and
female body are regulated by Folicle-stimulating hormone (FSH) and
Luteinizing (LH) from the pituitary glandule. In males, FSH stimulates
production
of sperm cells while in females it stimulates the
growth of the ovum. And LH, in males, stimulates the Leydig cells in
order to produce testosterone, and in females, stimulates
hormones preparing the body for pregnancy, as well as playing an important role in ovulation.
