System that transports nutrients and wastes and plays a role in the immune response

Which beat describes the brain stem

What can be said about farmers in highly developed countries? a) they have little or no negative impact on the environment. b) they practice subsistence agriculture. c) they are able to incorporate polyculture into their farming practices. d) they utilize organic farming techniques on a regular basis. e) they rely on large amounts of energy from fossil fuels.

All ova contain sex chromosomes corresponding to: x y xx xy