A child develops symptoms of chicken pox, produces antibodies against its specific antigens, and recovers from the illness. Later as an adult, he is immune to another exposure to the chicken pox virus. This is an example of which type of immunity

Contrast how pollination is different among gymnosperms and angiosperms.

Discuss the functions of epithelial connective nerviud and muscular tissues

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?