Male reproductive system Flashcards
What is the overall purpose of the male reproductive tract?
The main aim is to propagate the species by producing, maturing, storing, and delivering spermatozoa to the female reproductive system.
What processes are involved in sperm maturation and storage?
Sperm maturation occurs in the epididymis over about 30 days, while storage occurs in the epididymis and vas deferens for several months.
What are seminal and prostatic secretions, and why are they important?
These secretions mix with sperm to form semen, providing nutrients and facilitating sperm mobility and survival within the female reproductive tract.
Which structures are included in the male reproductive tract?
Key structures include the penis, scrotum, seminal vesicle, testis, epididymis, vas deferens, prostate, bulbourethral gland, ejaculatory duct, and urethra.
What role does the cremaster muscle play?
The cremaster muscle helps raise and lower the testes to control temperature, protecting sperm development.
What is the function of the scrotum in the male reproductive system?
The scrotum holds and regulates the temperature of the testes, keeping them cooler than body temperature for optimal sperm production.
What divides the testis into lobules?
The septum divides the testis into lobules, each containing seminiferous tubules and Leydig cells.
What is the role of Leydig cells?
Leydig cells produce testosterone, which regulates spermatogenesis and influences secondary sexual characteristics.
What is contained within the seminiferous tubules?
Seminiferous tubules contain developing sperm cells, Sertoli cells, and peritubular myoid cells.
What cell types are found in the seminiferous tubules?
Cell types include Leydig cells, Sertoli cells, peritubular myoid cells, spermatogonia, spermatocytes, spermatids, and spermatozoa.
Why are peritubular myoid cells important in the seminiferous tubules?
Peritubular myoid cells provide structural support and assist in the transport of spermatozoa through gentle contractions.
What function do Sertoli cells perform?
Sertoli cells support, nourish, and protect developing sperm and form the blood-testis barrier.
What is the function of tight junctions in Sertoli cells?
Tight junctions between Sertoli cells create the blood-testis barrier, which protects developing sperm from immune responses.
What is the purpose of the basement membrane in the seminiferous tubules?
The basement membrane supports the structure of the seminiferous epithelium, where spermatogenesis occurs.
Name the four types of spermatogenic cells found in the seminiferous tubules.
Spermatogenic cells include spermatogonia, spermatocytes, spermatids, and spermatozoa.
What two compartments are created by the blood-testis barrier?
The blood-testis barrier creates a basal compartment and an adluminal compartment, isolating certain stages of sperm cells.
Why is the blood-testis barrier considered an “immunologically privileged” site?
It prevents immune cells from attacking sperm cells, which could be recognized as foreign by the body.
What types of cells are located in the basal compartment?
The basal compartment contains Type B spermatogonia and early primary spermatocytes.
What process takes place during spermatocytogenesis?
During spermatocytogenesis, spermatogonia divide by mitosis to form primary spermatocytes.
What are the three main phases of spermatogenesis?
Spermatogenesis includes spermatocytogenesis (mitosis), the spermatocyte phase (meiosis), and spermiogenesis (maturation).
How long does spermatogenesis take from start to finish?
Spermatogenesis takes approximately 70 to 80 days.
What is the role of primary spermatocytes in spermatogenesis?
Primary spermatocytes undergo Meiosis I to produce secondary spermatocytes.
What happens to secondary spermatocytes in Meiosis II?
Secondary spermatocytes divide in Meiosis II to form haploid spermatids.
Where in the seminiferous tubule does the spermatocyte phase occur?
The spermatocyte phase occurs in the adluminal compartment of the seminiferous tubules.
What significant structure forms during the Golgi phase of spermiogenesis?
The acrosomal vesicle forms from Golgi enzymes, which will become the acrosome on the sperm head.
Why is the acrosome important?
The acrosome contains enzymes essential for penetrating the egg during fertilization.
Where is the acrosomal vesicle located in the developing spermatid?
The acrosomal vesicle forms near the nucleus in the spermatid.
What physical change occurs in the nucleus during the maturation phase?
The nucleus condenses, making the sperm head more compact.
What happens to excess cytoplasm during spermiogenesis?
Excess cytoplasm is shed and later phagocytosed by Sertoli cells.
What structure provides energy for sperm motility?
Mitochondria migrate to the midpiece, providing energy for the flagellum.
What hormones are produced by Leydig cells?
Leydig cells produce testosterone, a hormone essential for male secondary sexual characteristics and spermatogenesis.
What is a characteristic feature of Leydig cells?
Leydig cells have large, pale vesicular nuclei and granular eosinophilic cytoplasm, typical of steroid-producing cells.
Where are Leydig cells located in the testis?
Leydig cells are located in the interstitial tissue between seminiferous tubules.
How does chemotherapy affect spermatogenesis?
Chemotherapy damages mitotic and meiotic spermatocytes, leading to a temporary or permanent loss of sperm production.