Answer:
The correct answer is option - d. Production of primary spermatocytes.
Explanation:
The accessory cells or supporting cells present within the seminiferous tubules of reproductive system termed as the Sertoli cells. They play various roles in the body and reproductive system.
Sertoli cells make blood-testis barrier in adjacent Sertoli cells in the seminiferous tubules. These cells secrete different types of enzymes and hormones such as inhibin which are also secreted by ovary and placenta in females. Sertoli cells produce seminiferous tubular fluid to provide nutrition to the sperm. Apoptotic germ cells are timely eliminated by these cells.
Thus, the correct answer is option D. Production of primary spermatocytes.
Answer: stroke volume
Explanation:
Stroke volume is the amount of blood ejected during ventricular contraction or for each stroke of the heart.
Answer:
Explanation:
Not only is the biota important, but the abiotic factors in the ocean are also important because both groups work together. The abiotic factors in the ocean help the ocean to 'work'. For example, phytoplankton (autotrophs) need light, nutrients, CO2 (dissolved gases) to photosynthesize.
Answer:
Heterozygous for the gene
Explanation:
Alleles are the possible alternative forms of a gene. An organism having two identical alleles of a gene is said to be homozygous for that gene. On the other hand, an organism having two dissimilar alleles for a gene is heterozygous for that gene.
For example, let's suppose that I^A and I^B are the two alleles for ABO blood type in humans. Here, an individual with one copy of I^A and one copy of I^B would be heterozygous for ABO blood type. On the other hand, genotypes I^AI^A and I^BI^B are homozygous for the ABO blood type gene.