Orlando Graves

Biology

17 February, 19:30

1) which structure regulates breathing rate in humans?

A) diaphragm

B) lungs

C) hypothalamus

D) medulla

2) the first forms of life on earth

A) appeared about 10,000 years ago

B) could easily maintain a stable internal environment

C) were single-celled

D) depended on the hypothalamus for thermo regulation.

In an embryo, the tissues that receive a nerve produce sprouting factor, which encourages nerves to grow and branch, while the nerve produces anti sprouting factor, which inhibits grow.

a. Positive feedback

b. Negative feedback

c. Thermoreglation

d. homeostasis