All animals have a system for exchanging carbon dioxide and oxygen with their surroundings. What do all of these systems have in common?

A. All involve the active transport of gases across membranes.
B. All include airways, such as the trachea, that carry air to the mouth.
C. All involve gas diffusion across moist, selectively permeable membranes.
D. All involve organs or tissues that are dedicated to gas exchange and fulfill
no other functions.

If water were a non polar molecule, how would its properties be different ? a.) water would be a much lighter molecule b.) water would be able to climb up inside plants c.)water would not be able to form hydrogen bonds d.) water would stick together much more strongly

Aboy jumps into a cold swimming pool and his body tempature goes down hus muscles ,blood vessels

Duchenne muscular dystrophy is a serious condition caused by a recessive allele of a gene on the human x chromosome. the patients have muscles that weaken over time because they have absent or decreased dystrophin, a muscle protein. they rarely live past their twenties. how likely is it for a woman to have this condition? a) women can never have this condition.b) one-fourth of the daughters of an affected man would have this condition.c) one-half of the daughters of an affected father and a carrier mother could have this condition.d) only if a woman is xxx could she have this condition.