Reproductive System

Male & Female

1. Basic Vocab

A. Gonads - Primary Sex Organs; Make Hormones

1. Testes In Males

2. Ovaries In Females

B. Gametes - Sex Cells;

• Spermatozoa (Mature Sperm)

• Ova (Mature Eggs)

male (♂), female (♀)

2. Male Reproductive System

A. Functions:

Make Sperm & Give It To Females

B. Structures: Big Pic

1. Testes (Sing. testis)

2. Duct System:

a. Epididymis

b. Vas (Ductus) Deferens

c. Urethra

3. Accessory Organs

a. Seminal Vesicles

b. Prostate

c. Bulbourethral Glands

4. External Genitalia:

a. Scrotum

b. Penis

C. Testes Strux

1. Tunica Albuginea - White, Fibrous CT Outer Layer

2. Divided Into Lobules

3. Each Lobule Holds 1-4 Highly Coiled Seminiferous Tubules - Where Sperm Is Made

4. Between The Tubes Are Interstitial Tissue With Leydig Cells: Produce Testosterone

5. The Tubules Converge & Lead To The Epididymis

The Duct System

D. Epididymis - Comma Shaped, Coiled Tube

• Site Of Sperm Maturation - Gain The Ability To Swim (~20 Days)

• Sperm Stored Here

E. vas (Ductus) Deferens - Muscular Tube (~45cm) That Moves Sperm From Epididymis To The Ejaculatory Duct

Vasectomy - Cutting The Vas Deferens To Prevent Sperm From Leaving

F. Urethra

• Tube From The Base Of The Urinary Bladder To The Tip Of The Penis

• Carries Both Urine & Semen

• Sperm Enter From The Ejaculatory Duct

The Accessory Organs

G. Seminal Vesicles

• 2 Finger Shaped Glands, Slightly INferior & Posterior To Bladder

• Secrete An Alkaline Fluid (Makes Up ~70% Of Semen) Into Ejaculatory Fluid

• Has Fructose To Fuel The Sperm

H. Prostate Gland

• Walnut Sized, Inferior To Bladder

• Urethra Passes Through It

• During Ejaculation It Contracts To Force Its Prostatic Fluid Into Urethra

• Has Chemicals To Help Sperm Swim & Survive

I. Bulbourethral (Couper’s) Gland

• 2 Pea-Sized Glands That Sit At The BAse Of Penis

• Secretes Clear, Mucus Fluid Which Provides Lubrication For Intercourse

External Genitalia

J. Scrotum

• Sac Of Skin That Houses Testes

• Muscle Under Skin Can Retract / Relax Scrotum To Regulate Temps (Ideally ~92F / 33C)

• Cooler Temp Help Keep Sperm Viable

K. Penis

3 Regions:

1. Root (Internal)

2. Shaft (Body)

3. Glans Penis - Tip That Contains Large Concentration Of Nerve Endings And Foreskin (Prepuce)

• Internally: 3 Areas Of Spongy Erectile Tissue

• Erections Occur When This Tissue Fills With Blood During Sexual Excitement

• Circumcision: Surgical Removal Of The Foreskin - A Hood Of Skin Covering The Glans Penis

Spermatogenesis

Spermatogenesis - The Process Of Making Sperm

• Occurs In The Seminiferous Tubules

• Begins At Puberty; Triggered By Follicle Stimulating Hormone (FSH)

• Continues Throughout Life

1. Steps

1. Cells Around The Outer Wall Of Tubules Called Spermatogenesis AKA Germ Cells (46 Chromosomes) Divided By Mitosis

• This Maintains Their Quantities

2. Some Spermatogenesis Grow Larger And Become Primary Spermatocytes

3. These Divide By Meiosis 1 - Secondary Spermatocytes

4. The 2 Secondary Spermatocytes Divide To Create 4 Spermatids - Immature Sperm With Partial Flagella

• Spermatozoa - Mature Sperm

Sertoli Cell - Nourish Developing Cells Through This Process

Sperm Cell

Head: Contains DNA And Enzymes That Allow The Sperm To Penetrate The Egg

Midpiece: Contains Mitochondria

Tail: A Flagellum

Hormones

A. Follicle Stimulating Hormone (FSH):

Secreted By Pituitary; Initiates Spermatogenesis

B. Testosterone - Secreted By Leydig Cells (Outside Tubules):

Initiates & Maintains Secondary Sex Characteristics

• Facial, Axillary, Pubic Hair Growth

• Deeper Voice

• Increase Muscle Mass

• Sex Drive

• Aggression

Females - 1. Structures

A. Ovary - Female Gonads

• Suspended By Ligaments Attached To Uterus

• Covered In Tunica Albuginea (CT)

• Has Many Follicles - An Oocyte (Immature Eggs) Surrounded By Follicle Cells

Female - Duct System

B. Uterine Tubes AKA Fallopian Tubes AKA Oviducts

• Tubes That Extend From Uterus To Ovaries

• SIte Of Fertilization

1. Fx: Conduct Egg To Uterus

2. Structure:

a. Lined With Ciliated Cells

b. End Of Tube Widens Like A Funnel: Infundibulum

c. Fimbria: Finger-Like Projections

• Reach & Sweep Egg Into Tube

Tubal Ligation - The Fallopian Tubes Are Cut, Tied, Or Blocked To Permanently Prevent Pregnancy

C. Uterus

• Pear Shaped, Muscular Organ Located Between Rectum And Bladder

• Site Of Implantation And Development

1. 3 Walls:

a. Endometrium - Inner Layer; Highly Vascular

b. Myometrium - Thick, Middle Layer Of Smooth Muscle Tissue

c. Perimetrium - Smooth Outer Layer

2. Cervix- Narrow Outlet That Protrudes Into Vagina

D. Vagina

• Muscular But Elastic Tube

• Site For Insertion Of The Penis & Deposition Of Sperm During Copulation (SEX)

• Acidic Secretions

Accessory Glands - Female

E. Bartholin’s Gland

• Two Bean Sized Glands Located On Either Side Of Vaginal Openings Under The Skin

• Secrete Clear, Alkaline Fluid For Lubrication During Sex

F. Mammary Glands (& Breasts)

• Develop Within The Breast When Pregnant

• Remains Active In The Lactating Breast - Prolactin

• Atrophies When A Women Ceases To Nurse

External Genitalia

G. Vulva

• External Genitals

1. Structures:

a. Mons Pubis - Mound Of Fat Over The Pubic Symphysis Covered By Pubic Hair

b. Labia Majora & Labia Minora - Folds Of Flesh On Either Side Of Vaginal Opening

• Covers And Protects Vulva And Opening Of Vagina

c. Clitoris - Small Mass Of Sensitive Erectile Tissue And Nerves, Under The Labia Minora

• Corresponds To Male Penis