Atomic mass is determined by the number of protons plus the number of neutrons
Its D, im pretty sure theres not starch or acid in our DNA
We should expect that the rat will have have more difficulty in learning the task compared to a normal rat. This is because the rat has been injected with a certain drug that oppresses the dopamine activity. And then the rat is placed in an operant chamber where a lever-pressing task is shaped through positive reinforcement.
Answer
At week 5-6 of gestation, the baby’s heart starts beating.
Explanation
Fertilization occurs in week 3 followed by implantation in week 4.In week 5 the levels of hormones increases with formation of the baby’s heart and circulation system. In week 6, the neutral tube closes followed by development of structures necessary to form eyes and ears. The head of the baby develops at week 7 followed by nose in week 8 and toes in week 9.
