BIO 308 Reproductive System

What is sexual reproduction?

A biparental process where offspring are not genetically identical to either parent.

What are gametes?

Sex cells produced by each parent; male gametes are sperm, and female gametes are eggs.

What is a zygote?

A fertilized egg that has a combination of both parents' genes.

What defines a male in terms of gametes?

The parent producing sperm and having a Y chromosome.

What defines a female in terms of gametes?

The parent producing eggs and lacking a Y chromosome.

What are the primary functions of the male reproductive system?

To produce sperm and introduce them into the female body.

What are the primary functions of the female reproductive system?

To produce eggs, receive sperm, provide for gametes' union, harbor the fetus, and nourish offspring.

What are primary sex organs?

Gonads that produce gametes; testes in males and ovaries in females.

What are secondary sex organs?

Organs other than gonads necessary for reproduction, such as the penis and vagina.

What are secondary sex characteristics?

Features that distinguish the sexes and influence mate attraction, developing at puberty.

What is chromosomal sex determination?

The presence of XX chromosomes in females and XY in males, determining the sex of the child.

What role does the SRY gene play in sexual differentiation?

It codes for the testes-determining factor (TDF), initiating the development of testes.

What happens to a fetus at 5 to 6 weeks of development?

Gonads begin to develop as gonadal ridges.

What is cryptorchidism?

A condition of undescended testes occurring in about 3% of male births.

What is the function of the scrotum?

To house the testes and maintain a cooler environment for sperm production.

What is the spermatic cord?

A bundle of fibrous connective tissue containing the ductus deferens, blood vessels, and nerves.

What are seminiferous tubules?

Ducts in the testes where sperm are produced.

What is the pathway of sperm from the testes to the urethra?

Seminiferous tubules → efferent ductules → epididymis → ductus deferens → ejaculatory duct.

What do seminal vesicles do?

They are glands that form 60% of semen and empty into the ejaculatory duct.

What is the role of the dartos muscle in the scrotum?

It contracts in cold temperatures, wrinkling the scrotum to reduce heat loss.

What is the function of the pampiniform plexus?

It acts as a countercurrent heat exchanger to regulate the temperature of the testes.

What is the significance of testosterone in male development?

It is secreted by the testes and is crucial for male sexual differentiation.

What happens to sperm if not ejaculated?

They disintegrate and are reabsorbed by the epididymis.

What are homologous structures in male and female external genitalia?

The penis is homologous to the clitoris, and the scrotum is homologous to the labia majora.

What is the function of the ejaculatory duct?

It is formed from the ductus deferens and seminal vesicle and empties into the urethra.

What are seminal vesicles?

A pair of glands located posterior to the bladder that empty into the ejaculatory duct and form 60% of semen.

What is the function of the prostate gland?

It surrounds the urethra and ejaculatory duct, producing a thin milky secretion that forms 30% of semen.

What do bulbourethral glands produce?

A clear slippery fluid (pre-ejaculate) that lubricates the head of the penis and neutralizes residual urine acidity.

What is the primary function of the penis?

To deposit semen in the vagina.

What are the main components of the penis?

An internal root, an externally visible shaft, and a glans (head).

What is the prepuce?

The foreskin that extends over the glans of the penis and is removed during circumcision.

What is the role of erectile tissue in the penis?

It fills with blood during sexual arousal, leading to an erection.

What are the two types of erectile tissue in the penis?

The corpus spongiosum and the corpora cavernosa.

What triggers the onset of puberty?

A surge of pituitary gonadotropins that awakens the reproductive system.

What age range typically marks the onset of puberty in boys?

Around age 14.

What hormone is primarily responsible for male secondary sexual characteristics?

Testosterone.

What is andropause?

A period of declining reproductive function in men, often starting in the early 50s.

What is erectile dysfunction?

The inability to produce or maintain an erection sufficient for intercourse.

What is the primary function of the female reproductive system?

To produce and deliver gametes, provide nutrition for fetal development, give birth, and nourish infants.

How long is the uterine tube (fallopian tube)?

About 10 cm long.

What is the infundibulum?

The flared, trumpet-shaped distal end of the uterine tube.

What is the function of the uterus?

To provide a source of nutrition for a growing fetus.

What are the three layers of the uterine wall?

Perimetrium (external serosa), myometrium (middle muscular layer), and endometrium (inner lining).

What is a Pap smear?

A procedure where loose cells from the cervix and vagina are removed and examined microscopically for early detection of cervical cancer.

What is the best protection against cervical cancer?

Early detection through regular Pap smears.

What is the significance of Class I cervical intraepithelial neoplasia?

It is mild dysplasia that usually clears on its own and requires repeat Pap and colposcopy.

What happens in Class II cervical intraepithelial neoplasia?

A biopsy is called for, and LEEP surgery may be performed to remove precancerous cells.

What is the role of the ovaries?

To produce egg cells (ova) and sex hormones.

What occurs during ovulation?

The follicle bursts and releases the egg.

What is the function of fimbriae?

Feathery projections on the infundibulum that help guide the egg into the uterine tube.

What is the cervical canal?

The passage that connects the lumen of the uterus to the vagina.

What is the function of cervical glands?

To secrete mucus that prevents the spread of microorganisms from the vagina to the uterus.

What is the endometrium?

The inner mucosa of the uterus.

What are the two layers of the endometrium?

The functional layer (shed during menstruation) and the basal layer (regenerates the functional layer).

What role does the endometrium play during pregnancy?

It is the site of attachment for the embryo and forms the maternal part of the placenta.

What is the vagina's primary function?

It serves as the birth canal and allows for the discharge of menstrual fluid, receipt of the penis and semen, and birth of the baby.

What are vaginal rugae?

Transverse friction ridges located at the lower end of the vagina.

What is the vulva?

The collective term for the external female genitalia.

What is the function of the clitoris?

It is an erectile, sensory organ that serves as the primary center for sexual stimulation.

What are the greater vestibular glands?

Glands that open into the vestibule for lubrication during sexual activity.

What happens to the mammary glands during pregnancy?

They develop within the breast and remain active during lactation.

What is the areola?

The pigmented area surrounding the nipple, containing capillaries and nerves.

What triggers the onset of puberty in girls?

Rising levels of GnRH stimulate the anterior pituitary to secrete FSH and LH.

What is thelarche?

The onset of breast development, the earliest noticeable sign of puberty.

What is menarche?

The first menstrual period, typically occurring around age 12.

What is the average age range for menopause?

Menopause usually occurs between the ages of 45 and 55.

What is oogenesis?

The process of egg development in females.

What are primordial follicles?

Follicles concentrated in the cortex of the ovary that wait 13 to 50 years before developing further.

What is the average length of the sexual cycle?

The sexual cycle averages 28 days but can vary from 20 to 45 days.

What are the three principal steps of the ovarian cycle?

Follicular phase, ovulation, and luteal phase.

What is the menstrual phase?

The phase where the endometrium builds up and then breaks down, resulting in vaginal discharge.

What is endometriosis?

The growth of endometrial tissue outside of the uterus, often causing pain and infertility.

What is the role of progesterone during the menstrual cycle?

It primarily acts on the uterus, preparing it for possible pregnancy in the second half of the cycle.

What is the significance of the corpus luteum?

It stimulates endometrial secretion and thickening during the luteal phase.

What is the function of the fimbriae of the uterine tube?

They help catch the oocyte after ovulation.

What is the role of cervical mucus during ovulation?

It becomes thinner and more stretchy, indicating the best time for conception.

What is mittelschmerz?

Twinges of pain experienced at the time of ovulation.

What hormonal changes occur during the follicular phase?

FSH stimulates follicles to grow and secrete estradiol, preparing for ovulation.

What happens if pregnancy does not occur after ovulation?

The endometrium breaks down, menstruation begins, and the cycle starts over.

What is the average duration of menstruation?

The menstrual phase averages about 5 days.