A. yes
I think.
also is that a reference to Three Days Grace- The good life?
it's an awesome band.
The reasons are:
- the blood is very low on nutrition
- the leech is not feeding itself regularly
The leech slows it metabolism a lot, so it can survive on very low nutrition. The blood is very low on nutrition, and it is the leech's food source, so the evolution made it preserve energy.
The leach doesn't have the opportunity to feed itself on regular basis, so it takes maximum advantage of any opportunity and consumes as much blood as possible so that it can survive long term when it will not have food at disposal.
The correct answer is "crossing over."
Cellular growth takes place under interphase, specifically under G1 phase of interphase wherein there is increase in cell proteins and structure. Duplication of chromosomes (or DNA synthesis) takes place under interphase, specifically under the S phase of interphase. In the S phase, there is also duplication of organelles. Crossing over takes place under prophase I of meiosis.