Reproductive system flash cards

What are primary sex organs?

testes in males and ovaries in females.

Males Accessory reproductive organs?

Males: Ducts

(epididymis, vas deferens),

glands (prostate,

seminal vesicles),

and penis.

What are primary sex organs?

testes in males and ovaries in females.

Males Accessory reproductive organs?

Males: Ducts

(epididymis, vas deferens),

glands (prostate,

seminal vesicles),

and penis.

Females reproductive organs?

Uterine tubes, uterus, vagina, and external genitalia (labia, clitoris).

What are accessory reproductive organs?

These include ducts, glands, and external genitalia that assist in the delivery, nourishment, or support of gametes and offspring.

What are the main functions of primary sex organs?

• Produce gametes:

• Secrete hormones:

• Produce gametes:

• Sperm in males, ova (eggs) in females

• Secrete hormones:

• Testosterone in males, estrogen and progesterone in females

What are the accessory glands in males?

1. Seminal vesicles

2. Prostate gland

3. Bulbo-urethral glands (Cowper’s glands)

3. Bulbo-urethral glands (Cowper’s glands)

3. release clear mucus that lubricates and neutralizes urine traces in the urethra before ejaculation

Prostate gland

secretes slightly acidic fluid with enzymes that activate sperm.

Seminal vesicleS

1. produce 70% of semen volume; secrete alkaline fluid with fructose to nourish sperm.

Why are the testes located in the scrotum?

Because sperm production requires a lower temperature than body temperature — about 3°C cooler.

How is this different from the ovaries?

Ovaries are located inside the abdominal cavity and do not require a cooler environment for egg development.

Which muscles aid in temperature maintenance in the scrotum?

• Dartos muscle

• Cremaster muscle

• Cremaster muscle

• skeletal muscle that raises or lowers the testes to regulate temperature

• Dartos muscle

• smooth muscle in scrotal skin; wrinkles the skin to reduce surface area and heat loss.

• Cremaster muscle – skeletal

When do testes descend into the scrotum?

• Normally descend by 7 months of fetal development.

What can happen if testes fails to descend?

• condition is called cryptorchidism, which can lead to infertility if not corrected because of the higher temperature inside the abdomen

Where is sperm produced?

In the seminiferous tubules of the testes.

Where is testosterone produced?

By the interstitial cells (Leydig cells) located in the connective tissue between seminiferous tubules.

How is sperm conveyed to the outside of the body?

Sperm travels from:

Seminiferous tubules → straight tubule → rete testis → efferent ductules → epididymis → vas deferens → ejaculatory duct → urethra → exits body via penis.

Where is sperm stored?

In the epididymis, where it also matures.

How is sperm expelled out?

During ejaculation, sperm is propelled through the vas deferens and out via the urethra using peristaltic contractions

What is the spermatic cord?

The spermatic cord contains blood vessels, nerves, lymphatics, and the vas deferens. It runs from the scrotum through the inguinal canal into the pelvic cavity.

What is a vasectomy?

A vasectomy is a form of male birth control in which the vas deferens is cut and sealed, preventing sperm from reaching the urethra during ejaculation. Sperm is still made but is reabsorbed

What is the advantage of the urethra being inside the corpus spongiosum?

The corpus spongiosum surrounds the urethra to prevent it from being pinched closed during erection, ensuring that semen can be properly ejaculated

What is the physiology of erection

• Triggered by parasympathetic nervous system; blood fills erectile tissues.

What is the physiology of ejaculation?

• Triggered by sympathetic nervous system; smooth muscles in ducts and glands contract to propel semen through the urethra and out the penis.

What advantage does male urethra have over female urethra?

The male urethra also has a dual function: it carries both urine and semen, while the female urethra only carries urine.

What urethra is larger male or females?

The male urethra is much longer (about 20 cm or 8 inches) compared to the female urethra (3–4 cm).

UTI are more common in woman why?

UTIs more common in women, because the short female urethra is closer to the anus, allowing bacteria easier access to the bladder.

What is the difference between semen

• Semen is a mixture of sperm and fluids secreted by the male accessory glands (seminal vesicles, prostate, and bulbo-urethral glands).

Semen provides?

nutrients, mobility support, and protection for sperm

What is the difference between Sperm ?

• individual male gametes that carry half of the genetic material (23 chromosomes).

What are some constituents of semen?

• Fructose

• Prostaglandins

• Relaxin

• Clotting factors

• Antibiotic chemicals

• Alkalinity

• Alkalinity

• neutralizes acidic vaginal and urethral environments)

• Antibiotic chemicals

• fight bacteria)

• Clotting factors

• help semen stick inside vagina briefly)

• Relaxin

• enhances sperm motility)

• enhances sperm motility)

• Prostaglandins

• thin cervical mucus and promote reverse uterine contractions)

• Fructose

• energy for sperm)

Why does semen coagulate?

Right after ejaculation, semen coagulates (thickens) due to clotting factors.

This helps the sperm stick to vaginal walls and prevents drainage out of the vagina.

Later, enzymes liquefy the semen so sperm can swim freely toward the egg

Which accessory gland secretes lubricating fluid?

• bulbo-urethral glands (Cowper’s glands) secrete mucus that lubricates the glans penis and neutralizes traces of acidic urine in the urethra.

What is their counterpart in females?

• greater vestibular glands (Bartholin’s glands), which also secrete mucus for vaginal lubrication

What are sustentocytes (Sertoli cells)?

are large supporting cells located in the walls of the seminiferous tubules

What is spermatogenesis?

sperm cell production that occurs in the seminiferous tubules of the testes. It begins at puberty and produces four haploid sperm from one diploid stem cell using mitosis and meiosis.

What is the structure of a sperm cell?

A mature sperm cell has three main parts:

1. Head

2. Midpiece

3. Tail (flagellum)

What is the function of each part of the sperm cell head?

• Contains the nucleus, which holds 23 chromosomes. Also contains the acrosome, which is a cap filled with enzymes that help the sperm penetrate the egg.

What is the function of Mid piece

• Packed with mitochondria, which produce ATP (energy) for movement.

• Tail (flagellum)

• Responsible for propelling the sperm forward with whip-like motion, allowing it to swim toward the egg.

What hormones regulate male reproductive function?

GnRH (Gonadotropin-releasing hormone)

2. FSH (Follicle-stimulating hormone)

3. LH (Luteinizing hormone

4. Testosterone

Describe the hormonal feedback loop for testosterone regulation.

• Hypothalamus releases GnRH → stimulates anterior pituitary.

• Anterior pituitary releases LH and FSH.

• LH → stimulates Leydig cells to produce testosterone.

• FSH → acts on Sertoli cells to promote spermatogenesis.

• High testosterone levels inhibit the release of GnRH and LH/FSH via negative feedback to maintain hormonal balance.

• Inhibin, released by Sertoli cells, also provides feedback to suppress FSH.

Where are the ovaries located?

side of the uterus in the female pelvic cavity.

What is their structure?

Each ovary is about the size of an almond and is held in place by ligaments (ovarian, suspensory, and mesovarium).

What is the structure of the ovary?

• Cortex

• Medulla

• Cortex

• houses ovarian follicles and developing oocytes

• Medulla

• contains blood vessels, lymphatics, and nerves

What is the function of ovarian follicles?

Ovarian follicles are fluid-filled sacs in the cortex of the ovary that each contain an immature egg (oocyte).

function of ovarian follicles?

• Supporting the maturation of the oocyte

• Releasing hormones (especially estrogen)

• Releasing the mature egg during ovulation

Describe the structure of the uterine (fallopian) tubes.

The uterine (fallopian) tubes are about 4 inches long and connect the ovaries to the uterus.

What is the infundibulum of the uterine tube?

It is the funnel-shaped opening near the ovary. It has fingerlike projections called fimbriae that help sweep the egg into the tube.

What is the ampulla of the uterine tube?

It is the wide, curved portion of the tube where fertilization usually occurs.

What is the isthmus of the uterine tube?

It is the narrow part of the uterine tube that connects directly to the uterus.

List the regions of the uterus

1. Fundus

2. Body

3. Isthmus

4. Cervix

fundus

the rounded top of the uterus, located above where the uterine tubes enter

Body

the main central portion of the uterus where implantation of a fertilized egg occurs

Isthmus

narrow lower portion just above the cervix

Cervix

the lower neck-like part that opens into the vagina; secretes mucus and dilates during labor

What are the three layers of the uterine wall?

1. Perimetrium

2. Myometrium

3. Endometrium

Endometrium

the inner lining; it thickens each month and is shed during menstruation if no pregnancy occurs; it’s also where a fertilized egg would implant

Myometrium

the thick muscular middle layer responsible for uterine contractions during labor

Perimetrium

the outermost layer; a thin serous covering

What is the structure Of the vagina

vagina is a thin-walled muscular tube about 3–4 inches long. It extends from the cervix to the outside of the body.

function of the vagina?

• Serves as the birth canal

• Acts as the passageway for menstrual flow

• Receives the penis and semen during intercourse

• Its walls secrete fluids and expand during childbirth

What are the external genitalia of the female?

The external genitalia are collectively called the vulva

Mons pubis

fatty area over the pubic bone for protection

Labia majora and labia minora

skin folds that protect the openings to the vagina and urethra

Clitoris

erectile tissue, highly sensitive, contributes to sexual pleasure

Vestibule

area enclosed by the labia minora, contains urethral and vaginal openings

Greater vestibular glands (Bartholin’s glands)

secrete mucus to lubricate the vaginal opening during arousal

What is the perineum?

is the diamond-shaped area between the pubic arch and the coccyx, bordered by the ischial tuberosities. It includes the external genitalia and anus.

What is an episiotomy?

is a surgical incision made in the perineum during childbirth to widen the vaginal opening and reduce the risk of tearing.

How are oogenesis and spermatogenesis similar?

• Both involve meiosis to produce haploid gametes.

• Both begin with a stem cell (oogonium or spermatogonium).

• Both are hormonally regulated.

How are oogenesis and spermatogenesis different

• Timing:
  

  • Spermatogenesis starts at puberty and continues through life.

  • Oogenesis begins before birth, pauses, and resumes at puberty — ends at menopause.

• Gamete Output:
  

  • Spermatogenesis produces millions of sperm daily.

  • Oogenesis typically results in one egg per month.

• Completion:
  

  • All stages of spermatogenesis occur continuously.

  • Oogenesis is interrupted at various stages (meiosis I and II complete only if fertilization occurs).

How is milk produced?

Milk is produced by alveolar glands in the mammary glands. These glands are stimulated after childbirth to begin secreting milk.

Which hormone is responsible for milk production?

Prolactin – released from the anterior pituitary, stimulates milk production in the mammary glands.

Which hormone is responsible for milk let-down (ejection)?

Oxytocin – released from the posterior pituitary, causes the milk to be ejected from the ducts when the infant suckles.

When does oogenesis begin and when does it stop?

Oogenesis begins before birth, pauses, and resumes at puberty. It continues monthly until menopause. Only one functional ovum is typically produced per cycle.

Primary oocyte:

the actual immature egg cell arrested in prophase I of meiosis

Primary follicle:

the structure that surrounds the primary oocyte and supports its development

Primordial follicle:

earliest stage, single layer of squamous cells

Primary follicle:

one or more layers of cuboidal cells surround oocyte

Secondary follicle:

fluid-filled spaces begin to form

Vesicular (Graafian) follicle:

fully mature, ready for ovulation

Which stage of the oocyte is expelled in ovulation?

A secondary oocyte, arrested in metaphase II, is expelled during ovulation.

Why is “secondary oocyte” a more accurate term than “egg”?

The term “egg” is misleading — technically, ovulation releases a secondary oocyte, which will only become a mature ovum if fertilization occurs.

What are the three phases of the ovarian cycle?

1. Follicular phase

   2. Ovulation

   3. Luteal phase

Follicular phase (Days 1–14):

1. follicle growth; FSH and estrogen levels rise

Ovulation- around Day 14)

LH surge causes release of secondary oocyte

Luteal phase (Days 15–28):

corpus luteum forms and secretes progesterone and some estrogen