If it has valves then it is a vein.
Answer:
The immune response is your body's third line of defense. In this response, your body releases B-Cells and T-Cells to fight the antigen and destroy it.
Explanation:
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Answer:
aquatic plants are water lily
Shaping. Each step in the learning process is called an approximation. An animal may be reinforced for each successive approximation toward the final goal of the desired trained behavior. Animals learn complex behaviors through shaping.
