Hypothesis and conclusion
The choice that is true of the energy that is passed from one trophic level to the next in a food chain is about 10% of the energy passed from one level to the next is released as heat. The correct answer is A.
The sign of lead poisoning in children would be impaired development.
Lead is very toxic to the brain, so lead poisoning will be especially dangerous in children when the brain is developing at a high rate. Damage to the brain will cause the children to have an impaired development and growth, gastrointestinal pain, or neurological issue like seizure.
I think it is because it's easier to "control". Like the books usually said that the nucleus is the control center of the nucleus, so if the nucleus located at the center or near center of the cell. So like easy contact, easy control, easy communication etc.