When jacob saw shadows of people behind him on the walls of the dark alley, his blood pressure increased and breathing rate sped up. these physical reactions were most directly regulated by his: ?

The answer is amygdala. This is the region of the brain that is responsible for emotional responses such as fear and anxiety. It is part of the limbic system and hence important in decision-making. It processes information and sends signals to the hypothalamus and other regions such as the locus coeruleus (that processes fear and panic as in this case).

both male and female gametes are produced by meiosis of the germ cells. therefore, both male and female gametes are haploid. one male and one female gamete unite during the fertilization to form the diploid zygote. in seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells.