The immune system and the nervous system maintain extensive communication, including 'hardwiring' of sympathetic and parasympathetic nerves to lymphoid organs. Neurotransmitters such as acetylcholine, norepinephrine, vasoactive intestinal peptide, substance P and histamine modulate immune activity.
A. parasitism. The plasmodium is helped while the human host, harmed.
b. mutualism. The bacteria is supplied with a living environment while the host human is supplied with vitamin K
Phagocytosis is the process by which immune cells engulf and then destroy bacteria
it would be C because kingdom is animalia, phylum is chordata, class is mammalia and order is carnivora and humans and tigers are both carnivors
