Practice Test for Quiz 6 Notes
Sustentacular Cells
- Functions:
- Structural support for spermatogonia development.
- Formation of the blood-testis barrier.
- Secretion of substances that stimulate mitosis of spermatogonia and initiation of meiosis.
- Provision of nutrients to spermatogenic cells.
- Phagocytosis of damaged spermatogenic cells and excess cytoplasm released from maturing spermatids.
- Production of androgen-binding protein and inhibin, which regulate spermatogenesis.
Leydig Cells and Myoid Cells
- Leydig Cells:
- Located between seminiferous tubules.
- Myoid Cells:
- Muscle-like cells surrounding seminiferous tubules.
- Contract to push sperm and fluid through the tubules.
Male Sexual Response
- Erection:
- Results from the engorgement of erectile tissue in the penis with blood.
- Parasympathetic reflex releases nitric oxide from endothelial cells, causing dilation of arterioles in the penis.
- Ejaculation:
- Expulsion of semen from the penis.
- Under sympathetic control.
Accessory Gland Contribution to Semen Volume
- Seminal Vesicles:
- Contribute 60-70% of semen volume.
- Prostate Gland:
- Contributes 20-30% of semen volume.
- Bulbourethral Gland:
- Contributes less than 5% to semen volume.
Seminal Vesicle Secretions
- Fructose:
- Nutrient used by sperm to make ATP (adenosine triphosphate).
- Prostaglandins:
- Contract smooth muscle and increase sperm viability.
- Coagulating Proteins and Enzymes:
- Form a clot of semen in the female reproductive tract.
- Citrate:
- Used by sperm to make ATP.
Cryptorchidism
- A disorder in which the testes fail to descend into the scrotum.
Oogenesis
- Definition:
- Production of female gametes.
- Location:
- Occurs in follicles within the ovarian cortex.
- Site of implantation of ovum.
- Nutritional support for fetus.
- Provides contractions during birth.
Mammary Glands
- Modified sweat glands for milk production.
Female Perineum
- Definition:
- Diamond-shaped region between the pubic arch, coccyx, and ischial tuberosities.
- Clinical Perineum:
- Area between the vagina and anus.
- Often the site of incision (episiotomy) during childbirth.
Uterus Layers
- Perimetrium:
- Myometrium:
- Thick middle smooth muscle layer.
- Endometrium:
Male Urethra
- Prostatic Urethra:
- Surrounded by the prostate gland.
- Spongy Urethra:
- Passes through the penis and ends at the external urethral orifice.
- Membranous Urethra:
- Passes through the external urethral sphincter.
Male External Anatomy
- Prepuce:
- Foreskin covering the glans penis, often removed during circumcision.
- Glans Penis:
- Enlarged end of the penis.
- Root:
- Connects to the pelvic bones.
Spermatogenesis
- Spermatogonia:
- Stem cells that begin spermatogenesis through mitosis.
- Primary Spermatocytes:
- Develop from spermatogonia through mitosis.
- Secondary Spermatocytes:
- Develop from primary spermatocytes via meiosis I.
- Spermatids:
- Develop from secondary spermatocytes via meiosis II.
Spermiogenesis
- Definition:
- Maturation process of spermatids into spermatozoa.
- Process:
- Spermatids elongate and shed excess cytoplasm.
- The acrosome forms over the nucleus to assist in fertilization.
- Sperm remains connected to sustentacular cells.
Emission and Expulsion
- Movement of sperm, testicular fluids, and secretions from the prostate gland and seminal vesicles into the urethra.
Female Reproductive Anatomy
- Ovary is main female gonad
Uterine Tubes
- Isthmus:
- Connects the uterine tube to the uterus.
- Ciliated Fimbriae:
- Cover the ovary at the end of the infundibulum.
- Ampulla:
- Fertilization usually occurs in the ampulla.
Penile Blood Flow During Erection
- Blood from the testicular arteries fills the vascular spaces of the corpora cavernosa of the penis, not the corpus spongiosum.
Prostate Gland Secretions
- Secretions:
- Citrate
- Prostate-specific antigens and enzymes
- Antimicrobial chemicals
- Fructose
- Fructose is secreted by seminal vesicles and citrate by the prostate gland.
Ploidy of Spermatogenic Cells
- Spermatogonia and primary spermatocytes are diploid (2n).
- Secondary spermatocytes and spermatids are haploid (n).
Clitoris
- Definition:
- Small structure corresponding to the corpora cavernosa of the penis.
- Engorges with blood and is innervated by sensory, motor, and autonomic fibers during sexual stimulation.
Ductus Deferens
- Muscularis of the ductus deferens consists of 3 layers of smooth muscle, not 1 circular and 2 longitudinal layers.
Male Duct System
- Epididymis, ductus deferens, ejaculatory duct, and urethra are parts of the male duct system.