Flashcards in Final Exam Learning objectives: Male Reproductive System Deck (32):
What are the components of the male reproductive system?
PEAT (penis, excretory ducts, accessory sex glands, testes
What is the function of Lyedig cells?
Secretes testosterone, insulin like protein 3, and oxytocin; provide endocrine function of testis
Secreted by Lyedig cells; testicle development, development of secondary sex glands, secondary sex characteristics, maintains spermatogenesis
Insulin like protein 3
Stimulates testicular descent. Marker for evaluating fertility
Contraction of smooth muscle tissue in vas deferens
What is the composition of seminiferous tubules?
Sertoli cells, spermatogonia, primary spermatocytes, secondary spermatocytes, spermatozoa
Columnar, pale staining nucleus, extend through thickness of epithelium, secretion of estrogens, and formation of the blood testis barrier.
What is the function of the blood-testis barrier?
Isolates haploid germ cells ( secondary spermatocytes, spermatids, and sperm), from blood stream and immune cells. Prevents immune response against sperm and infertility
Large, spherical, basally located with variable morphology. Undergo mitosis to form continuous supply of germ cells
Second layer of cells adjacent to spermatogonia, undergo DNA replication (2n and 4d), then division into secondary spermatocytes (2n and 2d)
Undergo meiosis division into 4 spermatids, smaller than primary Spermatocytes, difficult to identify
Small round to tadpole shaped cells, thick layer of cells nearest lumen of seminiferous tubule
1) contains head, body, tail
2) crescent shaped lies along surface of testicle
3) outside tunica Albiginea epididymus
4) connective tissue septae from inner tunica albuginea segregated organ into lobules
Connective tissue cord extending through long axis of testis
Complex series of channels within the mediastinum; receives fluid from seminiferous tubules; connects to head of epididymis
Lined with alternating clumps of tall ( ciliated) and short (microvilli) pseudostratified epithelial cells
(Body, tail) Lined with pseudostratified ciliated columnar epithelium
Epididymus ( function)
Storage and maturation of sperm, removal of degenerating sperm, decapacitation factor added to sperm surface
(Vas deferens) longest segment of excurrent duct system, continuation of tail of Epididymus, glandular and non glandular segments
Structure and Function of Testicles
1) Paired Ovoid organ, housed withing scrotum, covered by dense connective tissue capsule (tunica albuginea), lobulated (lobuli testis), divided by connective tissue (septuli testis) house leydig cells, seminiferous tubules house (sertoli cells, spermatogonia, spermatocytes, and spermatids) depending on the region of the seminiferous tubule.
Developmental stages of spermatogenesis
1) Spermatogonia (some cells undego mitosis to retain sperm producing cells, some undergo meiotic division to produce primary and secondary spermatocytes) 2) Primary spermatocytes replicate their DNA before the first round of meiosis 2n chromosomally (normal amount), but twice the amount of 4d DNA 3) Reductive division 1n chromosomally to 2d (normal amount of DNA) to produce secondary spermatocytes 4) Secondary spermatocytes undergo reductive division to produce spermatids 1n chromosomally and 1d (half amount of DNA) (overall, spermatogenesis takes 74 days) and 12 days to enter the epididymis
Structure of epididymis
The head of the e.pididymis is made up of the efferent ductules, while the body and tail are made up of the ductus epididmis, the tail of the epidiymis is continued as the ductus deferens
1) Produced in the seminiferous tubules, straight tubule (tubuli recti), rete testis, efferent ductules, ductus epididymis, ductus deferens (vas deferens), intrapelvic portion of the urethra.
1) Corpus Cavernosum (erectile tissue in center) 2) Covered by dense connective tissue tunica albuginea penis 3) penile bulb - cavernous erectile tissue called the corpus spongiosum penis, lacks trabeculae has more erectile tissue houses urethra 4) Glans portion of the penis (free portion of the penis)
Erection and ejaculation
1) Cavernous erectile tissue fills with blood in response to the parasympathetic nervous system (blood flow increases to penile spaces while decreasing venous return) 2) Erectile spaces fill causing penis to increase in length and girth 3) Penis inserted into vagina 4) sympathetic nervous systems stimulates release of secretions from secondary sex glands into the urethra 5) Rhythmic contractions of skeletal muscle covering the carvernous erectile tissue causes propelling and release of ejaculate out of the penis.
Accessory sex glands
Vapb (Vesicular glands, Ampulla of vas deferens, Prostate, and bulbourethral gland)
secondary sex gland that secretes whitish substance that supports oocytes and spermatozoa
secondary sex gland secretes fluid that provides fructose rich energy for ejaculated spermatozoa
Secondary sex glands secretes (citric acid, fibrinolysins (enzymes liquefy sperm in vagina), and PSA (marker for cancer).
secondary sex characteristics secretes the majority of pre-seminal fluid (libricates urethra and vagina & may play an important role in energy for spermatozoa
1) Arises from the neck of the bladder passes through the pelvic cavity and continues through the penis 2) horizontally folded mucosa, and transitional epithelium also has erectile tissue