The answer would be catalyst.
Answer:
Diffusion
Explanation:
Diffusion is the spontaneous movement of gases, without the use of any energy or effort by the body, between the alveoli and the capillaries in the lungs.
I'd say the answer is C but I'm not 100% sure. If not C then maybe B
Passive transport<span> is a kind of </span>transport<span> by which ions or molecules move along a concentration gradient, which </span>means<span> movement from an area of higher concentration to an area of lower concentration. Examples of passive </span>transport<span>include diffusion, filtration, and osmosis.</span>
<h3>
<u>Answer and explanation;</u></h3>
<u>Zone of resting cartilage</u> is nearest to the epiphysis and contains randomly arranged chondrocytes that do not divide rapidly.
<u>Zone of Proliferation</u> produce new cartilage through interstitial cartilage growth. Chondrocytes divide and form columns resembling stacks of plates or coins.
<u>Zone of hypertrophy.</u> The chondrocytes produced in the zone of proliferation mature and enlarge, the cells nearest the diaphysis are older and undergoing hypertrophy.
Thus, a maturation gradient exists in each column: The cells nearer the epiphysis are younger and actively proliferating, whereas the cells progressively nearer the diaphysis are older and undergoing hypertrophy.
<u>Zone of Calcification</u> is a very thin zone that contains hypertrophied chondrocytes and calcified cartilage matrix. calcified cartilage is replaced by bone.
The hypertrophied chondrocytes die, and blood vessels from the diaphysis grow into the area.