Anatomy and Physiology - Chapter 26: The Reproductive System

Reproductive system

Organ system that functions to produce offspring

Gametes

Specialized cells for sexual reproduction: sperm in males and ova (eggs) in females

Fertilization

The process of combining the genetic information from the male and female gametes (sperm and egg) to form a zygote

Zygote

The fertilized egg formed after sperm and egg fuse; it is the first cell of a new individual, from which all body cells will develop.

Gestation

Development of the fetus`

Parturition

Process of giving birth

Gonad

Primary reproductive organ; i.e.,the testis of the male or the ovary of the female

Sex Hormones

Hormones such as testosterone in males and estrogens and progesterone in females that are essential for the development and function of reproductive organs and influence sexual behavior and drives

Accessory Reproductive Organs

Structures that assist in reproduction but are not involved in producing gametes, such as ducts, glands, and external genitalia

Gonadotropin-releasing hormone (GnRH)

Hormone released by the hypothalamus that indirectly stimulates the testes or ovaries by triggering FSH and LH release

Follicle-stimulating hormone (FSH)

Hormone produced by the anterior pituitary that stimulates ovarian follicle development in females and sperm production in males

Luteinizing Hormone (LH)

Anterior pituitary hormone that aids maturation of ovarian cells and triggers ovulation in females. In males, it stimulates interstitial endocrine cells of the testes to produce testosterone.

Puberty

The period of life when reproductive maturity is achieved, reproductive organs grow to adult size, and become functional.

Meiosis

Nuclear division process that reduces the chromosomal number by half and results in the formation of four haploid cells

Homologous

A pair of chromosomes, one from each parent, that carry genes for the same traits, though they may differ in the specific genetic instructions

Testes

Sperm-producing male gonads

Scrotum

External sac enclosing the testes

Epididymis

Portion of the male duct system where sperm mature and are stored

Ductus (vas) defenses

Extends from the epididymis to the urethra; propels sperm into the urethra by peristalsis during ejaculation

Urethra

Canal through which urine passes from the bladder (and semen passes from the ejaculatory duct in males) to the outside of the body

Penis

Male organ of copulation and urination

Perineum

That region of the body spanning between the ischial tuberosities, extending from the pubic arch to the coccyx

Prostate

Accessory reproductive gland that produces one-third of semen volume and helps propel it during ejaculation

Benign Prostatic Hyperplasia (BPH)

Characterized by benign (noncancerous) growth of both the stroma and glands, resulting in constriction of the prostatic urethra.

Prostatitis

Inflammation of the prostate gland

Bulbo-urethral glands

Produce a thick, clear mucus that neutralizes traces of acidic urine in the spongy urethra and lubricates the glans penis during sexual excitement

Semen

Milky white, somewhat sticky mixture containing sperm and secretions of the male accessory reproductive glands

Ejaculation

Expulsion of semen into the vagina

Erection

Enlargement and stiffening of the penis caused by the erectile tissues filling with blood

Erectile Dysfunction (ED)

The inability to achieve or maintain an erection firm enough for sexual intercourse.

Spermatogenesis

The process of sperm (male gamete) formation; involves meiosis

Ovarian Cycle

Monthly cycle of follicle development, ovulation, and corpus luteum formation in an ovary

Ovaries

The female gonads; produce female gametes (ova) and the sex hormones estrogen and progesterone.

Estrogens

Female sex hormone that stimulates female secondary sex characteristics and supports reproductive functions

Progesterone

Hormone partly responsible for preparing the uterus for the fertilized ovum

Ovarian Ligament

Anchors the ovary medially to the uterus

Suspensory Ligament

Ligament connecting the ovary to the pelvic wall

Mesovarium

Suspends the ovary in the broad ligament

Broad Ligament

A peritoneal fold that “tents” over the uterus, supporting the uterine tubes, uterus, and vagina, and encloses the ovarian ligaments

Uterine Tubes

Tube through which the ovum is transported to the uterus, also called the fallopian tube

Ectopic Pregnancy

Pregnancy where the fertilized egg implants outside the uterus, usually in the fallopian tube

Uterus

Hollow, thick-walled, muscular organ that receives, retains, and nourishes the fertilized egg; the site where the embryo/fetus develops

Prolapse of the uterus

Condition where the uterus descends into the vaginal canal due to weakened muscles

Vagina

Thin-walled tube extending from the cervix to the body exterior; often called the birth canal

Vaginal Fornix

A recess around the cervix where the upper end of the vagina encircles the tip of the cervix

Mammary glands

Milk-producing glands of the breast

Areola

Circular, pigmented area surrounding the nipple

Oogenesis

Process of ovum (female gamete) formation

Follicular Phase

First part of the ovarian cycle (days 1–14) when follicles grow, estrogen increases, and one follicle is picked to release an egg

Luteal Phase

Days 14–28 of the ovarian cycle; the corpus luteum is active and produces hormones to support possible pregnancy

Ovulation

Ejection of an oocyte (immature egg) from the ovary

Menarche

Establishment of menstrual function; the first menstrual period

Amenorrhea

The absence of menstruation