I belive the answer is a sand bar!
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.
High rates of
volcanism, earthquakes, and mountain building are the sites of subduction
zones. They occur in convergent boundaries found in tectonic plates of both
oceanic and continental crusts. Subduction zones occur when one tectonic plate
moves under another tectonic plate, sinking into the mantle as the plates
converge again.
<span>
Regions that are
within subduction zones experience an average rate of convergence of 2-8
centimeters per year. They are subject to many earthquakes because of the
collisions that occur within the tectonic plates. </span>
Answer:
C, D
Explanation:
The common property of all proteins is that they consist of long chains of α-amino (alpha amino) acids. The general structure of α-amino acids is shown in . The α-amino acids are so called because the α-carbon atom in the molecule carries an amino group (―NH2); the α-carbon atom also carries a carboxyl group (―COOH).
