In human development, which are these must be present before tissue is formed

What type of cell is produced after fertilization occurs and the gametes combines ?

Natural resources are any materials that humans obtain from the earth to meet our wants and needs.

Science which of the following is an example of a cyclic behavior that is seasonal? i think the answer is d, i just need to double check : ). a. running from predators. b. searching for water. c. hunting at night. d. migrating for warmth. ***