CH27 SQ REPRODUCTIVE SYSTEMS
A&P II Study Questions: Chapter 27 - Reproductive Systems (Male & Female)
1. Primary Functions of the Reproductive System
Produce, store, and transport gametes
Male gametes: sperm
Female gametes: oocytes
Enable fertilization
The union of sperm and oocyte.
Support development of the embryo/fetus
Occurs in females.
Produce sex hormones
Male hormones: testosterone
Female hormones: estrogen, progesterone
2. Scrotum
Definition: A sac of skin and superficial fascia that holds the testes outside the body cavity to regulate temperature.
3. Temperature for Sperm Production
Ideal Temperature: Approximately 34–35°C (93–95°F)
This is about 2–3°C below core body temperature, essential for effective sperm production.
4. Dartos Muscle
Function: A smooth muscle in the scrotal wall.
Purpose: It wrinkles the scrotal skin to reduce heat loss and helps regulate testicular temperature.
5. Cremaster Muscle
Function: A skeletal muscle that elevates the testes toward the body.
Purpose: Activated during cold conditions or sexual arousal; helps maintain proper temperature for sperm production.
6. Tunica Vaginalis
Description: A double-layered serous membrane surrounding each testis.
Layers: Parietal and visceral layers.
Derivation: It is derived from the peritoneum during testicular descent.
7. Tunica Albuginea
Composition: A thick, fibrous dense connective tissue capsule surrounding each testis.
8. Function of the Seminiferous Tubules
Role: Sites of sperm production (spermatogenesis).
9. Main Types of Cells in Seminiferous Tubules & Their Functions
Spermatogenic cells: Form sperm.
Sustentacular (Sertoli) cells: Support, nourish spermatogenic cells, and form the blood–testis barrier.
Myoid cells: Help move sperm and fluid through the seminiferous tubules.
Interstitial (Leydig) cells: Located between the tubules; responsible for testosterone secretion.
10. Location of Tubuli Recti
Definition: Short straight tubes connecting seminiferous tubules to the rete testis.
11. Rete Testis
Definition: A network of tubules located in the posterior testis, responsible for collecting sperm from the tubuli recti.
12. Efferent Ductules
Location: Found between the rete testis and the head of the epididymis.
13. Interstitial Cells
Location: In the connective tissue between seminiferous tubules.
Function: Produce testosterone.
Other Name: Also called Leydig cells.
14. Structures Found in the Spermatic Cord
Components:
Ductus deferens
Testicular artery
Pampiniform venous plexus
Autonomic nerves
Lymphatics
Cremaster muscle fibers
15. Structures Seen in a Sagittal Section of the Penis
Components:
Corpora cavernosa (paired)
Corpus spongiosum (surrounds urethra)
Spongy urethra
Glans penis
Urethral orifice
16. Erectile Tissue
Definition: Spongy vascular tissue with sinusoidal spaces that fill with blood during erection.
Comprises the corpora cavernosa and corpus spongiosum.
17. Cross-Section of the Penis
Structure:
Two corpora cavernosa (dorsal arrangement)
One corpus spongiosum (ventral, surrounds urethra)
Surrounded by the tunica albuginea
Deep fascia and skin outside.
18. Epididymis
Description: A long, coiled tube attached to the testis.
Function: Stores, matures, and transports sperm.
19. Function of the Ductus Deferens
Role: Transports sperm from the epididymis to the ejaculatory duct via peristaltic contractions.
20. Location of the Ejaculatory Duct
Location: Within the prostate gland; formed by the ductus deferens and the seminal vesicle duct.
21. Regions of the Male Urethra
Three Regions:
Prostatic urethra
Membranous urethra
Spongy (penile) urethra
22. Order of Ducts Sperm Travel
Pathway:
Seminiferous tubules → tubuli recti → rete testis → efferent ductules → epididymis → ductus deferens → ejaculatory duct → urethra → exterior
23. Male Accessory Glands
Three Glands:
Seminal vesicles
Prostate gland
Bulbourethral glands
24. Seminal Vesicles
Location: Posterior to bladder, near the ejaculatory duct.
Function: Produce alkaline, fructose-rich fluid, which accounts for approximately 70% of semen volume.
25. Prostate Gland Secretions
Composition: Milky, slightly acidic fluid containing citrate, prostate-specific antigen (PSA), and enzymes necessary to activate sperm.
26. Bulbourethral (Cowper’s) Glands
Function: Secrete clear, alkaline mucus that neutralizes acidic urine in the urethra and provides lubrication.
27. Semen
Definition: A mixture comprising:
Sperm
Seminal vesicle fluid
Prostatic fluid
Bulbourethral fluid
28. Male Sexual Response
Three Events:
Erection: Involves parasympathetic stimulation and vasodilation.
Emission: The movement of sperm and fluids into the urethra (sympathetic).
Ejaculation: The expulsion of semen via skeletal muscle contractions (somatic reflex).
29. Haploid vs Diploid Nucleus
Diploid (2n): Contains 46 chromosomes (typical of somatic cells).
Haploid (n): Contains 23 chromosomes (typical of gametes).
30. Meiosis
Definition: A two-division process that produces haploid gametes and generates genetic variation.
31. Phases of Meiosis
Meiosis I:
Prophase I
Metaphase I
Anaphase I
Telophase I
Meiosis II:
Prophase II
Metaphase II
Anaphase II
Telophase II
32. Significant Events in Meiosis I that Cause Variation
Crossing Over: Occurs during Prophase I, contributing to genetic diversity.
Independent Assortment of Chromosomes: Takes place in Metaphase I, further enhancing genetic variation.
33. Events & Cells of Spermatogenesis
Spermatogonia: Undergo mitosis.
Primary Spermatocyte: Undergoes meiosis I.
Secondary Spermatocytes: Undergo meiosis II.
Spermatids: Mature through spermiogenesis to become spermatozoa.
34. Type A vs Type B Spermatogonia
Type A: Stem cells that remain at the basement membrane.
Type B: Differentiate into primary spermatocytes, initiating spermatogenesis.
35. Spermatogenesis vs Spermiogenesis
Spermatogenesis: The formation of haploid spermatids via meiosis.
Spermiogenesis: The maturation process of spermatids into spermatozoa, involving only structural changes.
36. Dual Functions of the Female Ovaries
Functions:
Produce oocytes.
Secrete female sex hormones (estrogen and progesterone).
37. Coverings of the Ovaries
Layers:
Germinal epithelium
Tunica albuginea (a fibrous capsule).
38. Regions of the Ovary & Their Contents
Cortex: Contains follicles and oocytes.
Medulla: Contains blood vessels, nerves, and connective tissue.
39. Four Types of Ovarian Follicles
Primordial: Contains a single squamous layer.
Primary: Composed of cuboidal granulosa cells.
Secondary: Characterized by multiple layers and the formation of an antrum.
Tertiary/Graafian: Contains a large antrum; is ready for ovulation.
40. Ovulation
Definition: The release of an oocyte from a mature follicle; typically occurs mid-cycle around day 14.
41. Uterine Tubes
Description: Paired tubes that receive the oocyte; also known as fallopian tubes or oviducts.
42. Parts of the Uterine Tubes
Components:
Infundibulum
Fimbriae
Ampulla (the primary site of fertilization)
Isthmus
43. Entry of the Oocyte into the Uterine Tube
Mechanism: The fimbriae sweep the oocyte into the uterine tube, where peristalsis and cilia assist in moving it toward the uterus.
44. Uterus
Description:
Composed of regions: fundus, body, cervix.
Functions: Receive, retain, nourish the embryo/fetus; facilitate expulsion of the fetus during childbirth.
45. Layers of the Uterine Wall
Composition:
Perimetrium
Myometrium
Endometrium (which includes functional and basal layers).
46. Spiral Arteries
Monthly Changes: They repeatedly degenerate and regenerate; their constriction causes menstruation.
47. Functions of the Vagina
Roles:
Copulation
Passage for menses
Birth canal.
48. Mucosa of the Vagina
Composition: Stratified squamous epithelium rich in glycogen, which produces an acidic environment.
49. Structures of the Vulva
Components:
Mons pubis
Labia majora
Labia minora
Clitoris
Vestibule
Urethral/vaginal openings
Vestibular glands.
50. Areola
Definition: The pigmented area around the nipple; contains sebaceous glands.
51. Function of Alveolar Glands
Role: Produce milk.
52. Lactiferous Ducts
Function: Carry milk from alveolar glands to the nipple.
53. Oogenesis
Definition: The formation of female gametes through meiosis.
54. Oogenesis vs Spermatogenesis
Oogenesis:
Begins before birth.
Produces one ovum and polar bodies.
Arrests between stages.
Spermatogenesis:
Begins at puberty.
Produces four sperm continuously.
55. Fate of Polar Bodies
Outcome: Polar bodies degenerate and do not participate in reproduction.
56. When Oogenesis Starts
Timing: Begins before birth, during the fetal period.
57. Phases of the Ovarian Cycle
Phases:
Follicular phase (development of follicles)
Ovulation
Luteal phase (formation of the corpus luteum).
58. Fate of the Corpus Luteum
Outcomes:
No pregnancy: transforms into corpus albicans.
Pregnancy: maintained by human chorionic gonadotropin (hCG) and continues to secrete hormones.
59. Hormones Regulating the Ovarian Cycle
Cascade:
Gonadotropin-releasing hormone (GnRH) stimulates the release of Follicle-stimulating hormone (FSH) and Luteinizing hormone (LH), which subsequently lead to estrogen and progesterone secretion from the ovaries.
60. Uterine Cycle
Definition: Another name for the cyclic changes of the endometrium; also known as the menstrual cycle.
61. Phases of the Uterine Cycle
Phases:
Menstrual phase: shedding of the endometrium.
Proliferative phase: rebuilding of the endometrium.
Secretory phase: nutrient-rich secretion to prepare for embryo.
62. Effects of Estrogen & Progesterone Outside the Uterus
Functions:
Stimulate bone growth
Influence secondary sex characteristics
Affect fat distribution
Alter cervical mucus consistency
Increase body temperature (influenced by progesterone).
63. Female Sexual Response
Three Phases:
Arousal: Involves vasodilation and engorgement of tissues.
Plateau: Characterized by increased secretions and muscle tension.
Orgasm: Involves pelvic muscle contractions and sympathetic discharge (there is no equivalent ejaculation for gametes in females).
64. Physiological Sources of Lubrication
Sources:
Greater vestibular (Bartholin’s) glands
Cervical mucus
Vaginal mucosal transudate (blood-filtered fluid).