Chapter 3

Sexual Bodies: Anatomy and Physiology

Homologous Structures

anatomical characteristics that share a common origin in fetal development and have many underlying similarities in structure and function

Secondary Sex Characteristics

Physical characteristics, other than the genitalia, that develop during adolescence, differ between the sexes, and indicate physical and sexual maturity

Mammary Glands

structures within the breasts capable of producing milk, formed principally of lobules and ducts which are grouped into lobes

Vulva

all visible parts of the external female genitalia including the labia and external clitoris, as well as adjacent structures including the vestibule of the vagina, urethra, and urethral meatus

Mons (mons pubis or mons veneris)

the pad of skin and fat above the clitoris, usually covered with pubic hair in an adult

Perineum in the Female

Area of skin between the anus and the vaginal opening

Clitoris

a highly innervated structure with several external and internal components that includes erectile tissue inside a female’s body

Vagina

the passage that exists between the vulva on the outside of the body (beginning at the labia minora) and the uterus

Vestibule

outermost portion of the vagina nearest the labia minora

Introitus

opening to the vaginal canal beyond the vestibule

Hymen

Fold of skin that partly covers the introitus

Graefenberg Spot (G-Spot)

a small, bean-shaped area of slightly raised or spongy tissue that is particularly sensitive in some females, relating to multiple internal structures, often located near the urethral sponge, on the front (anterior) wall of the vagina between the urethral opening and the cervix

Skene Glands

a system of glands that all women have that surrounds the urethra and secretes fluid during arousal and orgasm

Pubococcygeus Muscle (PC Muscle)

one of a group of muscles attached to the pelvis; these are involved in both sexes in the control of urinary flow and orgasm and also in females during childbirth

Cervix

at the upper portion of the vaginal canal, firmer tissue that is the lowermost portion of the uterus

Uterus

structure containing tissues that approx every 4 weeks for a fertile female swells with blood vessels to get ready for implantation of a fertilized egg and during pregnancy holds the placenta containing a developing fetus but in the absence of implantation expels this additional part of the lining as menstrual flow or menses; also called womb

Fallopian Tubes

structures that branch out from the upper portion of the uterus and connect to the ovaries

Ovaries

structures that contain egg cells and produce hormones that affect the development and functioning of many tissues in fetuses, adolescents, and adults

Menarche

first period

Female Genital Cutting (FGC or female genital mutilation)

Cultural practice associated with honor and purity, involving removal of part or all the clitoris and other parts of the vulva

Vaginal Fistula (Obstetric Fistula)

a tearing that opens a passage between the vagina and bladder or colon, which is a condition that affects millions of adolescents and adults in the developing world

Gynecomastia

development of breast tissue in males

Galactorrhea

Lactation in males

Penis

portion of the male genitalia analogous to the clitoris in females but largely external to the body and with multiple erectile structures contained in a single tube of skin

Scrotum

sac of skin that holds the testes

Perineum

area of skin between the anus and the scrotum

Glans (Glans Penis)

flared head of the penis containing many nerve endings; swells during arousal

Pearly penile papules

small dome-like bumps typically around the corona on the glans of the penis that are white in color; common in many males, especially earlier in adulthood, may be visible but are usually so small as to be nearly unnoticeable

Phallus

artistic or symbolic representation of the penis/male power

Cremaster Muscle

muscle tissues that can draw the testes closer or farther from the body to regulate temperature

Tunica Dartos

muscles tissue that can wrinkle or smooth the skin of the scrotum to regulate testes temperature and distance from the body

Corpus Cavernosa

two tubelike structures running on either side down the length of the penis

Carpus Spongiosum

single spongy structure running down the length of the penis, on the underside, underneath the two cavernous bodies; also called the spongy body. The urethra runs inside the spongiosum

Epididymis

contains structures that surround each testis; functions include nourishing, concentrating, and transporting sperm cells

Vas Deferens

single curled tube transporting sperm cells prior ejaculation

Prostate Gland

a structure that produces approx 30% of seminal fluid; located where the vas deferens, seminal vesicles, and urethra

Seminal Vesicles

structures whose secretions constitute approx 70% of the volume of semen

Benign Prostatic Hyperplasia (BPH)

a common condition in older males where the prostate gland enlarges

Vestigial Characteristic

a trait that has no adaptive function in an evolutionary sense but remains in some form, having descended from an ancestral species for which the trait was adaptive