To perform a testcross, scientists cross an organism with an unknown genotype with a homozygous recessive organism.
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Answer:
C
Explanation:
The nucleus contains most of the dna and the mitochondria contains a small amount
Answer:
Sertoli cells
Explanation:
The Sertoli cells nourish and protect the developing sperm cells, and spermatogenesis—the developmental pathway from germ cell to mature sperm—occurs in the recesses of the Sertoli cells (Figure 19.17)