1.true 2.false 3.the diffusion of water across a membrane 4.Rr
In humans, the yolk sac is the
site of origin for blood cells and primordial germ cells. The human yolk sac is
a membrane located outside the embryo and it is connected by a tube through the
umbilical opening to the embryo's midgut. The yolk sac serves as an early site
for the formation of blood and in time, is incorporated into the primitive gut
of the embryo.
Answer:
i think is a but im not sure but i hope it helps.
Explanation:
During a baseball game, a player’s ball hit into the outfield is modeled by the equation h = –16t2 + 65t. A bird flying across the field follows the path modeled by the equation h = 8t + 20. Let t be the time since the ball is hit and h be the height.
