Video Transcript
What is the correct sequence of processes that occur in sperm production? (A) Multiplication, growth, maturation, metamorphosis. (B) Growth, multiplication, metamorphosis, maturation. (C) Multiplication, maturation, growth, metamorphosis. (D) Multiplication, growth, metamorphosis, maturation. Or (E) metamorphosis, growth, maturation, multiplication.
This question is asking us to put the stages of sperm production, which is also known as spermatogenesis, in the correct order. Spermatogenesis, which occurs in the seminiferous tubules in the testes of a biological male, converts diploid primary germ cells into haploid mature sperm cells, which are capable of fertilizing an egg cell.
Let’s take a look at an overview of the different stages of spermatogenesis. The first stage of spermatogenesis is called the multiplication phase, which begins where the biological male is still in utero, so it’s not yet been born. It includes many mitotic divisions of the diploid primary germ cells to eventually develop into a large number of diploid spermatogonia following birth. The spermatogonia then enter the growth phase during which they divide by mitosis and differentiate into diploid primary spermatocytes. During the growth phase, the primary spermatocytes replicate the genetic information so that each cell contains 46 replicated chromosomes. They are now ready for meiosis.
The primary spermatocytes then enter the maturation phase where they undergo meiosis, which you might recall consists of two rounds of division: meiosis one and meiosis two. Meiosis one halves the number of chromosomes in the primary spermatocytes, converting them into haploid secondary spermatocytes. In meiosis two, the secondary spermatocytes are converted into spermatids, which are also haploid. In the final phase, metamorphosis, the spermatids develop a tail and other specialized features and develop into haploid mature sperm cells.
So the correct sequence of stages in sperm production is (A): multiplication, growth, maturation, metamorphosis.
