Male and Female Reproductive Systems

Did you know? The reproductive system is the only system not designed for the survival of the individual, but the survival of the species The female egg cell is the largest human cell 500 million sperm are produced per day in a mature male The ovaries of a newborn girl have about 600,000 eggs A female is capable of giving birth to about 35 children in her lifetime

Male Reproductive system Male External Organs Scrotum & penis Male scrotum is outside the body to keep sperm just outside body. Sperm viable just below body temp. When temperature is too low, scrotum retracts towards the body When too hot, scrotum distends further away from the body Both are covered by skin

Penis Urethra- 2 Corpora Cavernosa Glans- head of penis Carries urine or semen 2 Corpora Cavernosa The erectile tissue with many small cavities fill with blood to form erection Glans- head of penis Corona- posterior border of glans

Male Reproductive System

Internally divided into many lobules Each lobule contains a seminiferous tubule Spermatogenesis takes place here Interstitial cells near septa that separate lobules Secrete testosterone Testes

Testosterone The “masculinizing hormone” Responsible for change in voice Stimulates protein anabolism  males usually more muscular /stronger Changes size and shape of bones Produces body and facial hair Maintains development of male accessory organs

Spermatogenesis-10 Weeks to Development 2N diploid  N haploid

Haploid package of genes Acrosome contains enzymes to penetrate the egg Middle section packed with mitochondria Flagella to swim Sperm With enzymes that help break through Zona pellucida that surrounds egg. flagellum

Sperm Facts Average of 180 million released at a time, can be up to 400 million Sperm count less than 60 million is considered clinically infertile Die in fresh water Die as they dry out Sperm can live in a female for up to 7 days

Accessory Ducts & Glands Seminal Vesicle- produces about 60% of seminal fluid. Proteins, enzymes, mucous, vitamin C, fructose Prostate Gland- produces a slightly basic fluid (7.3 pH) to help neutralize acidity of vagina to preserve sperm. 10-30% of seminal fluid Bulbourethral Gland (Cowper’s Gland)- produces clear pre-ejaculate to lubricate urethra and neutralize urine residue Ejaculatory Duct- Semen passes through during ejaculation

Male Fertility Testing Sperm counts Fructose levels Motility Structure

Disorders of Male Reproductive Testicular Cancer- Most common cancer in males under 40 Male teens should learn testicular examinations to feel for tumor growth Hernia- Portion of intestines breaks through abdominal wall into scrotum Prostate Cancer Prostate grows with age, and can become cancerous Rare under 40 Pain passing urine or slow passage Highly treatable if detected early STDs

Circumcision

Post Vasectomy Sperm Counts to ensure successful

Female Reproductive System Female External Genitalia- Vulva

Ovaries Made of several thousand ovarian follicles Each contains an ovum Produce one mature ovum per month Produce sex cells & hormones Estrogen & Progesterone

Female Reproductive System

Ovum Development Each ovum is in a follicle Each follicle goes through a cycle of development each month releasing estrogen When egg is released from mature follicle, ovulation occurs Corpus Luteum- follicle without egg that produces progesterone, necessary to maintain pregnancy

Fallopian Tubes Not connected to ovary Eggs are discharged into abdomen and find their way to fallopian tubes Lined with cilia to help move egg towards uterus

Uterus About the size of a pear Lies behind bladder Late stages of pregnancy moves up and can push on diaphragm Almost all muscle Grows considerably to hold baby & fluid Cervix is lower narrow section

Functions of Uterus Three functions Menstruation Low levels of hormones after 14 days after ovulation trigger shedding of endometrium Repairs itself after in preparation for pregnancy Pregnancy Labor

Vagina Made of smooth muscle Lined with a mucous membrane Organ that sperm enters Organ baby exits

Breasts Lies over pectoral muscles Mostly fatty tissue 15-20 radially arranged lobes containing several lobules Lobules contain milk-secreting cells Cells arranged in grape-like clusters called alveoli Alveoli drain into lactiferous ducts that head towards nipple Areolar colored region around nipple Turns from pink to brown in early pregnancy

Menstrual Cycle Typically 28 days Consists of changes in Three phases Menstruation Postmenstrual Premenstrual One ovum matures per month for 30-40 years Consists of changes in Breasts Uterus Ovaries Vagina Anterior Pituitary secretion of hormones

Ovulation 1st day of period is 1st day of cycle Ovulation occurs 14 days before next period Cycle may vary in length of days Ovum only lives short time after it is ejected

Hormones Involved Follicle Stimulating Hormone (FSH)- stimulates ovarian follicle to start growing and secreting estrogen Estrogen- Responsible for breast growth, thickening of endometrium Leteinizing Hormone (LH)- triggered by elevated blood estrogen. Causes maturation of ovum & follicle, ovulation, and formation of corpus luteum Progesterone- secreted by corpus luteum and helps maintain pregnancy. If pregnant, placenta maintains level, if not, levels drop and menstruation occurs

Cycling of Hormones

Menstrual Cycle

How does “The Pill” work? A 21 day combination of estrogen & progesterone Suppresses FSH & prevents ovulation Last 7 pills are placebo to maintain practice of pill taking Antibiotics, anti-seizure, migrane medicine reduce effectiveness of pill Does NOT protect against STDs

Female Disorders/Conditions Endometriosis Endometrial lining grows outside of the uterus Very painful periods Abnormal bleeding Could cause infertility Fibroids Benign tumors Pain, heaviness in abdomen Menopause Mechanisms of menstruation cease to function due to age Ovarian Cysts May cause pelvic or abdominal pain or bleeding if rupture Most commonly benign but should be investigated Result of follicles growing too large Many go away on their own HPV & STDs

Ectopic Pregnancy

Tubal Ligation