What period represents the last 2 million years of geological time

During the process of meiosis, special cells called gametes are formed. gametes only have half the number of chromosomes that the other cells in the body have. what form of reproduction do organisms that produce gametes use?

9. the history of life on earth is recorded in

Which of the following describes the difference in stimuli required to detect a difference between the stimuli? a. just noticeableb. signal detectionc. subliminald. top down