Answer:
B
Explanation:
I believe it is meiosis because there are two parts in which it helps to increase genetic variety. In prophase 1, the genes cross over, which increases the variety. Also, the chromosomes are assigned randomly in Metaphase 1.
Hope this helps:)
D.
They have the same number of protons as electrons.
Explanation:
Protons are found in the nucleus of the atom and have a positive charge while electrons orbit around the nucleus and have a negative charge. Usually, in a neutral atom of an element, the number of protons is equal to the number of electrons. This is why the atom has no charge because the positive and negative charges cancel out. When an atom loses an electron its charge turns positive while when it gains an electron its charge turns negative.
Answer:
Mechanical digestion begins in the mouth as the food is chewed. Chemical digestion involves breaking down the food into simpler nutrients that can be used by the cells.
Explanation:
Chemical digestion begins in the mouth when food mixes with saliva. Saliva contains an enzyme (amylase) that begins the breakdown of carbohydrates.
The planets appeared to move backward in the sky occasionally.
