Answer:
Function of each male reproductive system-
They produce, maintain and transport sperm and semen . They discharge sperm into the female reproductive tract. They produce and secrete male sex hormones.
Function of each female reproductive system-
The ovaries produce the egg cells, called the ova or oocytes. The oocytes are then transported to the fallopian tube where fertilization by a sperm may occur.
Answer - A
The ratio of a child with clear skin with that of freckled skin is 1:2.
When genotype rr mates with genotype Rr, the following genotypes are expected:
Rr = clear skin dominant
rr= freckled skin
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All mentioned complexes (receptor-hormone, antibody-antigen, enzyme-substate) are involved in a molecular recognition.The molecular recognition involves <span>non-covalent </span> interaction between molecules. To form complex, molecules must be complementary in shape and charges, and usually, they are compared to key and lock. This way, the selectivity and specificity of recognition between molecules are assured.