repro

• Scrotum


  Loose skin and underlying subcutaneous layer that hangs from the root (attached portion) of the penis
• Scrotum


  • Raphe - median ridge that separates scrotum into lateral portions externally
  • Scrotal septum - divides the scrotum into two sacs (each contains a single testis); made of dartos muscle
  • Cremaster muscle - series of small bands of skeletal muscle that surround the testes
  • Cremaster muscle and dartos muscle contracts to move testes closer to body to absorb heat also (and appears to be wrinkled/tight to reduce heat loss) in cold weather
• Testes/Testicles


  Paired oval glands in the scrotum; 5 cm long and 2.5 cm in diameter

  
• Testes/Testicles


  • Testis mass = 10–15 g
  • Tunica vaginalis - serous membrane that partially covers the testes
  • Tunica albuginea - fibrous capsule composed of dense irregular connective tissue
  • Seminiferous tubules – 1-3 tightly coiled tubules from 200–300 lobules; where sperms are produced

  
• Spermatogenic cells


  Cells in the seminiferous tubules that produce sperm
• Sertoli cells


  Cells in the seminiferous tubules that support and nourish the spermatogenic cells
• Leydig (interstitial) cells


  Clusters of cells in the spaces between adjacent seminiferous tubules that secrete hormones
• Androgen


  Hormone secreted by Leydig cells
• Testosterone


  Hormone secreted by Leydig cells
• Urethra


  Runs the length of the penis from the bladder to the meatus
• Penis


  Flaccid penis fills with blood during arousal, causing an erection and allowing for the function of copulation/intercourse
• Smegma


  Lubricant produced under the prepuce on the penis
• Foreskin


  Covers the glans/head of the penis that is filled with nerve endings
• Vas deferens


  Muscular tubes transporting sperm from the epididymis to the seminal vesicles
• Seminal vesicles


  Produce a slightly alkaline fluid that mixes with the sperm and becomes part of the semen ejaculated during the male orgasm. It protects the sperm from the acidity of the urethra.
• Prostate gland


  Secretes an alkaline fluid that mixes with the sperm as part of the semen. Enlargement of the prostate, benign prostatic hyperplasia, obstructs the flow of urine through the urethra.
• Cowper's or bulbourethral glands


  Produce another mucous-alkaline secretion in the urethra, excreted from the glands just before ejaculation
• Seminal fluid


  • Constitutes about 60% of the volume of semen and contributes to sperm viability
  • The prostate secretes a slightly acidic fluid that constitutes about 25% of the volume of semen and contributes to sperm motility
  • The bulbourethral (Cowper's) glands secrete mucus for lubrication and an alkaline substance that neutralizes acid
• Semen

  Mixture of sperm and seminal fluid; it provides the fluid in which sperm are transported, supplies nutrients, and neutralizes the acidity of the male urethra and the vagina
• Penis


  Consists of a root, a body, and a glans penis. Engorgement of the penile blood sinuses under the influence of sexual excitation is called erection
• Mons Pubis


  Rounded, soft fullness of subcutaneous fatty tissue, prominence over the symphysis pubis that forms the anterior border of the external reproductive organs. Covered with varying amounts of pubic hair.
• Uterus


  A hollow, muscular, pear-shaped organ about the size of a woman's clenched fist. Top is tipped forward in a normal 'anteflexion' position. Can be divided into the body or corpus, and the bottom cervix. The rounded top portion, above the fallopian tubes, is called the fundus.

  
• Uterus


  • Trauma, disease, or multiple pregnancies can weaken the ligaments supporting uterus, and result in abnormal positioning
  • Provides a place for the protection and nourishment of the fetus during pregnancy
  • Contracts during labor to expel the fetus
• Perimetrium


  Outer layer of the uterus
• Myometrium


  Muscular inner layer of the uterus
• Endometrium


  Mucous membrane lining the uterus; sheds the lining of the uterus every 21 to 40 days by menstruation
• Fallopian tubes

  • Tube widens to form the ampulla
  • The isthmus is the portion that connects to uterus
  • Fimbria are the finger-like projections around the opening that trap the egg as it leaves the ovary
  • End of tube is called the infundibulum
  • Opening is called the ostium
  • Fallopian tube is 4-6 inches long
• Fallopian tubes


  1. Egg is released from the ovary, captured by the fimbria and brought into the fallopian tube

  2. The egg is moved along inside the tube by muscular contractions and the waving action of cilia

  3. It takes an egg about 3-4 days to travel the length of the tube. If an egg is fertilized, it occurs here.
• Ovaries

  • The two ovaries are attached to each side of the uterus by a ligament
  • Oval-shaped, about the size of a large olive, and lie close to the fimbria at the end of the fallopian tubes
  • Each ovary is filled, already at birth, with egg-containing sacs called follicles. Each egg is called an ovum.
• Ovaries

  1. Once every 21 days, one follicle in one ovary ripens. This mature follicle is a graafian follicle.

  2. The follicle ruptures in response to hormones from the pituitary gland, releasing the ovum/egg a process called ovulation.

  3. After the follicle ruptures, it becomes a mass of yellow cells called the corpus luteum. This is a temporary, progesterone-producing structure.
• Vagina

  • Extends from the cervix to the outside of the body
  • It is a 3 ½ inch long muscular tube that expands in length and width during sexual arousal
  • The vagina is the female organ for copulation (sexual intercourse), receiving the seminal fluid from the male penis
  • Also a passageway for menstruation or the birth of a fetus.
• Vulva


  The 5 organs making up the external genitalia of the female: Mons pubis, Labia majora, Labia minora, Vestibule, Clitoris
• Breasts


  • The mammary glands, varying in size according to age, heredity, and the amount of fatty tissue present
  • Each breast has 15-20 glandular lobes separated by connective tissue
  • After childbirth, the pituitary gland stimulates these lobules with the hormone prolactin they produce milk.
• Areola


  The dark-colored circle at the tip of the breast
• Nipple


  Where ducts from the lobules open
• Colostrum


  The first secretion from the breast, a thin yellowish substance that contains nutrients and the mother's immunities that can protect baby
• Menarche


  Onset of the menstrual cycle; begins at puberty and ceases at menopause
• Menstrual cycle


  1. Follicular phase - characterized by menstruation, when the thickened lining of the endometrium is shed because no egg was fertilized or implanted. Just prior to this phase is a premenstrual period characterized by hormonal and physical changes.

  2. Ovulatory phase - Estrogen is the hormone produced by the ovaries, which stimulates the maturation of a follicle and thickens the endometrium.

  3. Luteal phase - follows ovulation, and is characterized by the development of the corpus luteum, the secretion of progesterone, the preparation of the endometrium for implantation of a fertilized egg, and the formation of a thick mucous to block the cervix once the egg passes out of the fallopian tube.
• Pregnancy


  1. The fertilized egg implants in the uterus. Progesterone production increases to signal a pregnancy; it can be detected in urine and blood.

  2. At the moment of conception, a single sperm penetrates/fertilizes a single egg resulting to zygote, with 46 chromosomes

  3. The zygote begins dividing and is also called a blastocyst. From week 2-8, it is called an embryo.

  4. The embryo is suspended in an amniotic sac surrounded by fluid during the 280 day gestation period.

  5. The umbilical cord attached at the navel connects it to the placenta, where it gets nutrients and oxygen.

  6. During the 1st trimester, all parts of the embryo are formed. During the second trimester all parts start to function; during the last trimester the embryo is now called a fetus and the main task is growth.
• Childbirth


  1. Labor, characterized by muscle contractions, dilation (to 10 cm) and effacement (thinning)of the cervix, and expulsion of the mucous plug that formed in the cervix, signals the onset of parturition (childbirth process)

  2. The cephalic, or head-first delivery, is the most common. Breech is a backward presentation; Caesarian is delivery through an incision in the abdomen.

  3. The umbilical cord is cut and clamped, and placenta (afterbirth) is delivered following birth of the baby.