Which happens during the second trimester?

A. The vocal cords develop.
B. The heart starts working.
C. Rhythmic breathing starts.
D. Blood begins to form.

Which term refers to the total dollar value of the goods and services produced in a country in a year?

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

Read the following statements that describe how information flows in the nervous system. what is the correct order in which they occur? 1) response is carried to glands or muscles. 2) information is gathered. 3) information is processed and a response is formed.