Chapter 12: Human Growth and Development Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The Male Reproductive System • Primary Organs – Gonads: testes • Accessory Structures – Ducts that transport sperm cells & hormones – Exocrine glands Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The Male Reproductive System (cont’d) Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Testes • 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Structure of the Testis Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Testosterone • 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) Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Spermatozoa • 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Accessory 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Semen • 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Common Diseases and Conditions of the Male Reproductive System • Enlarged prostate • Prostate cancer • Testicular cancer • Orchitis • Cryptorchidism • Epididymitis Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The Female Reproductive System • Ovaries – Female gonads – Site of egg formation • Accessory Structures – Uterus – Various passageways – Bartholin glands – External genitalia – Breasts Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The Female Reproductive System (cont’d) Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The Female Reproductive System (cont’d) Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Accessory Structures • Fallopian tubes • Uterus • Vagina • Bartholin glands • Vulva & perineum • Breasts Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins The 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Common Diseases and Conditions of the Female Reproductive System • Cervical cancer • Endometriosis • Ovarian tumors • Fibroid tumors • Pelvic inflammatory disease • Menstrual disorders • Uterine cancer • Yeast infection • Breast cancer Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Effects of Aging on the Reproductive System • Men: decrease in testosterone production • Women: menopause—menstruation gradually ceases Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Common Diseases and Conditions of Both the Male & Female Reproductive Systems • Chlamydia • Gonorrhea • Syphilis • Genital herpes • Human papillomavirus (HPV) • Pubic lice • Infertility Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Factors 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 Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Stages of Growth and Development • Embryo & fetus • Adolescent (12-18 years) • Neonate (birth to 1 month) • Young adult (18-40 years) • Infant (1 month to 1 year) • Toddler (1-3 years) • Preschool child (3-6 years) • Middle-aged adult (40-65 years) • Older adult (>65 years) • School-aged child (6-12 years) Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Stages of Grief 1. Denial 2. Anger 3. Bargaining 4. Depression 5. Acceptance Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins Theories of Development • Erik Erikson • Robert J. Havighurst • Sigmund Freud • Maslow’s hierarchy of needs Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins