Answer:
To reduce water loss.
Explanation:
Keeping the stomata closed during the day, helps reduce water loss when dry, hot wind blows across it.
When prey is abundant, predator populations increase because more young are able to survive. More predators kill more prey, which, along with food scarcity, decreases the population. When prey becomes more scarce, the predator population declines until prey is again more abundant. Therefore, the two balance each other.
The primary function of estrogens in women is development of female sexual characteristics during puberty. (Breasts, regulation of the menstrual cycle etc.)
In males estrogen helps in maturation of the sperm and maintenance of a healthy libido.
Explanation:
In simple diffusion, small molecules without charges such as oxygen and carbon dioxide flow through a plasma membrane without assistance and without expending energy. Other substances such as proteins, glucose and charged particles called ions cannot pass through the selectively permeable membrane