Answer:
b
Explanation:
earth's ocean did grew higher over time because o rainfall for the last 20 years!
2019 years have humans been on earth
Ok, think about it. Does your skin prevent germs from getting inside you?
Does your skin prevent water from leaving the body too quickly? Does your skin protect your insides from getting damaged when you fall? Do you put food on your skin to absorb nutrients, or do you put food in your mouth like a normal person?
Positive selection tests to see if the TCR of a T-lymphocyte can recognize and bind to an MHC molecule.
<h3>What is a T-lymphocyte?</h3>
A T-lymphocyte is a special type of immune cell that is generated inside the bone marrow.
The T-cell receptor (abbreviated as TCR) is a protein located on these immune T lymphocytes.
In conclusion, Positive selection identifies if the TCR of a T-lymphocyte can recognize and bind to an MHC molecule.
Learn more about T-lymphocytes here:
brainly.com/question/17025187
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