Homeostasis is maintained by the respiratory system in two ways: gas exchange and regulation of blood pH. Gas exchange is performed by the lungs by eliminating carbon dioxide, a waste product given off by cellular respiration.
<span>The
most important estrogen is estradiol and the most important androgen is
testosterone.</span>
Testosterone
is the primary steroid male sex hormone. Its function is to control the development
of male reproductive tissues, to promote secondary sexual characteristics to
maintain health (the prevention of osteoporosis for example). It is synthesized
from cholesterol and it achieves its effects by binding to androgen receptors
on different tissues.
Answer:
1. Essential organs form during early development
Explanation:
Harmful chemicals (toxins) cause the most disease when they are present during fetal development, because organ systems are being developed and the rate of growth is very fast.