Answer:
The preferable option will be - A.
A. similar environments and specific traits increased their chances of survival.
Explanation:
- The shark and dolphins have similar body shape and fins. But shark is a fish and dolphin is a mammal.
- Both of them are exposed to similar kind of environments. Both of them possess a specific kind of alternative characters and traits.
- So, Some species may have similar body structures even if they are not related because they evolved in similar environments and specific traits increased their chances of survival.
The wings are adapted so they can hover and feed off of flowers.
The beak and tong is modified to extract nectar from flowers with long flower corollas.
Answer:
Testes and ovaries produce two types of hormones:
androgens (male sex hormones)
estrogens (female full hormones)
In each type of gland, both types of hormones are secreted only in different amounts: the ovaries secrete more estrogen than the androgen hormones, and the sperm inversely.
Explanation:
In testicular tissue, Leydig cells produce androgen hormones: androsterone and testosterone. The ovaries produce a group of estrogen hormones and progesterone. These hormones exert their effect at puberty when the glands are activated. At puberty, the pituitary gonadostimulins activate the sex glands, whose activity leads to the development of secondary sex characteristics (the appearance of first menstruation in girls, beards and mustaches in boys, etc.).