Answer:
A. keeps you healthy
Explanation:
The immune system protects your body from outside "invaders," such as bacteria, viruses, fungi, and toxins.
Answer:
a. DNA carries instructions for the functions of every cell and enzyme in living organisms.
b. DNA can serve as a way to identify one individual from another.
Explanation:
Which of the following is TRUE about DNA?
a. DNA carries instructions for the functions of every cell and enzyme in living organisms.
b. DNA can serve as a way to identify one individual from another.
c. All living organisms can carry DNA in practically every cell of their body
The main responsible for the delay among the atrial and
ventricular contractions is the action potential conduction velocity of the AV
node cells. If the atria and ventricles contract simultaneously, atria cannot
give any help in filling the ventricles, which is needed, especially in those
with stiff ventricles as in the elderly. Hence atria have to contract first and
then the ventricles.
A) Crossing over is the mechanism of genetic variation that results from the exchange of gene segments between non-sister chomatids.
Three of the four nitrogenous bases that make up RNA — adenine (A), cytosine (C), and guanine (G) — are also found in DNA. In RNA, however, a base called uracil (U) replaces thymine (T) as the complementary nucleotide to adenine (Figure 3). ... (Remember, DNA is almost always in a double-stranded helical form.)
