Male Reproduction Flashcards
What cells do sperm arise from?
Spermatogonial stem cells
Where does mitotic division occur in sperm production?
Basal layer of sertoli cells in the seminiferous tubules in the testis
How many chromosomes to spermatogonia have?
46
What happens to the residual body of a sperm?
It is phagocytosed by the sertoli cells
What do the seminiferous tubules run into?
The rete testis
What is an orchidectomy?
Removal of a testis
What occurs if the testes do not descend to the scrotum?
Cryptorchidism
What does the rete testis run into?
The epididymis
What does the epididymis run into?
The vas deferens
What occurs in the epididymis?
Sperm acquire the ability to be motile and fertilise.
Excess fluid is also reabsorbed making the sperm 100x more concentrated
How long to sperm spend in the epididymis?
10-14 days
What is the ampulla?
Wider region of vas deferens which contains very concentrated sperm storage
How long can sperm be stored in the vas deferns?
Several months
What is the function of the seminiferous tubules?
Produce sperm
Where are the seminiferous tubules located?
The testes
What is the name of the cell in which a sperm first starts to be made?
Sertoli cell
What is found outside of the seminiferous tubules?
Leydig cells
At what stage in life does spermatogenesis begin?
After puberty
How much does the average testis weigh?
18g
How many sperm does the average male produce per second?
300-600 sperm per gram of testis tissue per second
What are the 3 stages of spermatogenesis?
Mitosis, Meiosis, Cytodifferentiation
What occurs during stage 1 of spermatogenesis?
Stage 1: Mitosis. A spermatogonial stem cell (2n) divides to produce 1 daughter cell (2n) and 1 spermatogonial stem cell. The daughter cell then migrates through the tight junctions of Sertoli cells into the adluminal compartment of the seminiferous tubule, where is is called a primary spermatocyte
What occurs during stage 2 of spermatogenesis?
Stage 2: Meiosis. The primary spermatocyte’s DNA content doubles (still 2n), and Meiosis 1 occurs, resulting in 2 secondary spermatocytes (n). Meiosis 2 occurs, producing 4 spermatids (n)