Answer: Primary Sex characters
Explanation:
The primary sexual characters are associated with the growth of sexual organs such as uterus, vagina, penis and other reproductive organs in the human beings.
These organs are present in the body when the child is borne. This is because they grow when the child is inside the womb.
The development and maturation of these organs takes place during the later stages of life.
A sudden inrush of water could over whelm animals and possibly kill them if the water is of a different type.
I believe you're looking for "invasive species"
Pituitary gland.
When you feel stress, the pituitary gland, at the base of the brain, increases its production of the hormone ACTH. This hormone tells the adrenal glands, found at the top of your kidneys, to increase their production of hormones. These stress hormones help you to concentrate, speed your reaction time, and boost your strength. Your hypothalamus also helps your body respond to stress.