Answer:
Option B, The controls on cell growth and divisions can be turned on and off
Explanation:
There are signal proteins that control and regulate the cell growth and division process. For instance, mitogens help in removing the negative controls which would otherwise have blocked the cell cycle progression. Then there are growth factors that synthesize proteins and hence stimulate cell growth. Also there are some survival factors that suppress the apoptosis. Based on these three factors the cell division and growth can be turned on or off.
Hence, option B is correct
<span>If you have hepatitis A infection you have inflammation in your liver that's caused by a
virus. Other symptoms of this virus are jaundice (yellow eyes and skin, dark urine), pain in
your belly, loss of appetite, nausea, fever, diarrhea and fatigue. </span>A vaccination against
this virus is unnecessary if you have been infected in the past.
The one in my opinion that best describes a leaf is tissue. it can't be the organism because that would be the tree itself. In a like fashion, it can't be the organ because the branches of the tree would be the organs. Since the leaves make up the branches... they would be tissues.
