Chapter 12: Human Growth and Development

Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins

Chapter 12: Human Growth and Development

Chapter 12: Human Growth and Development


The Male Reproductive SystemThe Male Reproductive System

• Primary Organs

– Gonads: testes

• Accessory Structures

– Ducts that transport sperm cells & hormones

– Exocrine glands


The Male Reproductive System (cont’d)The Male Reproductive System (cont’d)


TestesTestes

• Located outside body, midline below torso

• Suspended by spermatic cord in scrotum

• Spermatic cord: bundle of blood & lymphatic vessels & nerves

• Oval-shaped

• Site of sperm generation

• Produce testosterone


Structure of the TestisStructure of the Testis


TestosteroneTestosterone

• Main male sex hormone

• Diffuses from testes into surrounding fluid & is absorbed into bloodstream

• Functions:

– Develops & maintains reproductive structures

– Develops sperm cells

– Develops secondary sex characteristics (deeper voice, body hair)


SpermatozoaSpermatozoa

• Sperm cells

• Fertilize egg cell

• >200 million in average ejaculation

• Manufactured continuously after puberty in testes

• Head: nucleus containing chromosomes, enzymes to penetrate ovum

• Tail: propels sperm through female reproductive system to reach ovum


Accessory StructuresAccessory Structures

• Epididymis– Coiled tube on surface of testes

– Stores sperm

• Vas deferens– Duct in spermatic cord

– Carries sperm to ejaculatory duct

• Ejaculatory duct– Delivers sperm to urethra

• Penis: delivers sperm to vagina during intercourse


SemenSemen

• Mix of sperm cells & secretions from other glands

• Expelled from body in ejaculation

• Functions of secretions in semen:– Nourish sperm cells

– Transport them

– Neutralize acidity of male urethra & female vaginal tract

– Lubricate female reproductive tract during intercourse

– Prevent infection by using antibacterial enzymes & antibodies


The Urethra and PenisThe Urethra and Penis

• Urethra– Tube that transports both urine & semen through pelvic cavity &

penis

– Ejection of semen made possible by erection

• Penis– Made of spongy tissue that engorges with blood when erect

– Contractions of skeletal muscles in pelvic floor expel semen

– Penis & scrotum make up male external genitalia


Common Diseases and Conditions of the Male Reproductive SystemCommon Diseases and Conditions of the Male Reproductive System

• Enlarged prostate

• Prostate cancer

• Testicular cancer

• Orchitis

• Cryptorchidism

• Epididymitis


The Female Reproductive SystemThe Female Reproductive System

• Ovaries– Female gonads

– Site of egg formation

• Accessory Structures– Uterus

– Various passageways

– Bartholin glands

– External genitalia

– Breasts


The Female Reproductive System (cont’d)The Female Reproductive System (cont’d)


The Female Reproductive System (cont’d)The Female Reproductive System (cont’d)


The OvariesThe Ovaries

• Outer layer consists of single layer of epithelium

• Ovarian follicle– Cluster of cells where ovum ripens

– Secretes estrogen, beginning development of endometrium

• Ovulation– Follicle ruptures & discharges ripened egg

• Menstruation– The sloughing off of endometrium

– Expulsion of unfertilized egg


Accessory StructuresAccessory Structures

• Fallopian tubes

• Uterus

• Vagina

• Bartholin glands

• Vulva & perineum

• Breasts


The Menstrual CycleThe Menstrual Cycle

• Process that prepares female’s body for pregnancy

• Egg ripens & is released

• Endometrium is prepared

• If no fertilization:

– Estrogen & progesterone levels decrease

– Bloody discharge

• Average duration: 2 to 6 days


Common Diseases and Conditions of the Female Reproductive SystemCommon Diseases and Conditions of the Female Reproductive System

• Cervical cancer

• Ovarian tumors

• Pelvic inflammatory disease

• Uterine cancer

• Breast cancer

• Endometriosis

• Fibroid tumors

• Menstrual disorders

• Yeast infection


Effects of Aging on the Reproductive SystemEffects of Aging on the Reproductive System

• Men: decrease in testosterone production

• Women: menopause—menstruation gradually ceases


Common Diseases and Conditions of Both the Male & Female Reproductive SystemsCommon Diseases and Conditions of Both the Male & Female Reproductive Systems

• Chlamydia

• Gonorrhea

• Syphilis

• Genital herpes

• Human papillomavirus (HPV)

• Pubic lice

• Infertility


Factors Influencing Growth and DevelopmentFactors Influencing Growth and Development

• Heredity

• Prenatal factors (mother’s age/health during pregnancy)

• Caregiver factors (mental illness)

• Individual differences (vision & hearing impairments)

• Health or illness

• Environment, including culture

• Nutrition


Stages of Growth and DevelopmentStages of Growth and Development

• Embryo & fetus

• Neonate (birth to 1 month)

• Infant (1 month to 1 year)

• Toddler (1-3 years)

• Preschool child (3-6 years)

• School-aged child (6-12 years)

• Adolescent (12-18 years)

• Young adult (18-40 years)

• Middle-aged adult (40-65 years)

• Older adult (>65 years)


Stages of GriefStages of Grief

1. Denial

2. Anger

3. Bargaining

4. Depression

5. Acceptance


Theories of DevelopmentTheories of Development

• Erik Erikson

• Robert J. Havighurst

• Sigmund Freud

• Maslow’s hierarchy of needs

Documents

Chapter 12: Human Growth and Development