Fast Biology Questions!!?

Question

1. In the term trace element, the modifier trace means

A. the element is required in very small amounts.

B. the element can be used as a label to trace atoms through an organism's metabolism.

C. the element is very rare on Earth.

D. the element enhances health but is not essential for the organism's long-term survival.

2. Compared to 31P, the radioactive isotope 32P has

A. a different atomic number.

B. one more neutron.

C. one more proton.

D. one more electron.

E. a different charge.

3. The reactivity of an atom arises from

A. the average distance of the outermost electron shell from the nucleus.

B. the existence of unpaired electrons in the valence shell.

C. the sum of the potential energies of all the electron shells.

D. the potential energy of the valence shell.

E. the energy difference between the s and p orbitals.

Answer 1

c, b, b

Answer 2

1.a

2.b

3.b