550 likes | 735 Views
Human. Reproduction. Sexual Reproduction in Human. testis. ovary. sperms. eggs (ova). fertilization. zygote. Blastocyst. embryo. fetus. baby. External Male Reproductive Organs. Penis Testes Scrotum. The Penis.
E N D
Human Reproduction
Sexual Reproduction in Human testis ovary sperms eggs (ova) fertilization zygote Blastocyst embryo fetus baby
External Male Reproductive Organs • Penis • Testes • Scrotum
The Penis • Tube-shaped organ that extends from trunk of the body just above the testes • Part of the body where semen is released (ejaculation) • Semen- thick fluid containing sperm and other secretions from the male reproductive system
Male Reproductive System Scrotum – sac of skin that holds testes. Hangs below body to keep testes cool. Sperm cannot be produced if body is too warm. Testes move into scrotum just before birth. Testis/testes –Made up of small, coiled tubes seminiferous tubules. 300-600 per testis. Immature sperm made here. • Secrete testosterone
Testis and epididymis epididymis vas deferens (sperm duct) sperm tubules
Internal Male Reproductive Organs • Epididymis • Vas Deferens • Seminal Vesicles • Prostate Gland • Cowpers Gland • Urethra
Epididymis • For temporarily storage of sperms • Where sperm Mature • During intercourse, muscles of epididymis contract to release sperms
Internal Organs Vas deferens– tubes that extend from each epididymis to the urethra Cowper’s gland, Prostate Gland, & Seminal vesicles–secretions from these glands combine with sperm-containing fluid to form semen
Male Reproductive System seminal vesicle secrete seminal fluid prostate gland Cowper’s gland
Functions of Seminal Fluid • To provide a medium for the sperms to swim • To activate and nourish the sperms • To neutralize the acidity in the female reproductive tract Seminal Fluid Semen Sperms +
Male Reproductive System 8. Urinary bladder – stores urine 9. Rectum- holds waste 10. Urethra – passageway for excretion of urine and sperm to leave body. Vas deferens empties into urethra
Male Concerns • Hernia- Part of body pushes through the muscle wall • Sterility- Sperm weak, may not be able to fertilize egg • Prostate Cancer- Uncontrolled growth of cells (radiation therapy/removal of prostate) • Testicular Cancer- Frequent in males 15-35 (self-check)
Preventing Problems • Prevent STI’s • Prevent trauma (athletic cups) • Prevent hernias (don’t lift things that are too heavy)
Male Reproductive System Urinary Bladder Seminal Vesicles Prostate Gland Urethra Penis Rectum Epididymis Cowper’s gland Testes Vas Deferens Scrotum
Functions of Ovary • Produce female gametes (ova/eggs) • For production of female sex hormones • Estrogen and Progesterone
Ovary • A female’s ovaries contain 400,000 immature eggs at birth. (all the eggs they will ever have) • Once a month during puberty, a mature egg is released into the fallopian tubes. This process is called ovulation.
Fallopian Tubes • Carries the ovum (egg) forward by • the beating action of the cilia on its inner surface • the contraction of muscles of fallopian tube
Female Reproductive System Fallopian tube – Each ovary is near but not connected to oviduct. Tube with funnel-like opening. Cilia line it to create a current that draws the egg into the tube. Egg is fertilized in the fallopian tube 3. Uterus – thick, muscular, pear-shaped organ. Once egg is fertilized it finishes its development in uterus attached to uterine wall
Female Reproductive System Urinary bladder – storage of urine Urethra – passage of urine to outside of body Vagina (birth canal) – leads to outside of body from the uterus Cervix – narrow neck of uterus Rectum – passage for wastes
Ovulation • The release of an ovum (egg) from an ovary • Every month, the fallopian tubes take turns releasing an egg. Right one month, left the next month
Female Reproductive System Fallopian tube ovary uterus cervix vagina
Menstrual Cycle • Menstruation occurs once a month, due to the uterus preparing itself for possible pregnancy. • If pregnancy doesn’t occur, the uterine lining breaks down into blood, tissue, and fluids and is released through the vagina.
Female Concerns • Infertility- Inability for female to become pregnant • Problems that can cause infertility • STD’S--PID Infection of the Fallopian Tubes • Blocked Fallopian Tubes- PID, Abdominal Surgery, Leading Cause Of Infertility • Endometriosis- Uterine tissue grows outside the uterus, often appearing on the ovaries, fallopian tubes and abdominal cavity
Other Female Reproductive Disorders • Vaginitis: Most common Vaginal infection in women of child bearing age. Caused by bacteria, accompanied by discharges, pain, itching… • Ovarian Cysts: Fluid filled sacs on the ovaries. Small and non-cancerous, usually they will disappear on their own. Larger cysts may require surgery
Concerns • Problems related to menstruation: • Menstrual cramps- Cramps in abdominal occur during menstrual period • Dysmenorrhea- Painful contractions lasting 1-2 days • Amenorrhea- Lack of menstruation by age of 16 or stopping of cycle for 3 or more months • (PMS) Premenstrual Syndrome- Symptoms are: nervous tension, anxiety, irritability, bloating, wt gain, depression, mood swings • (TSS) Toxic Shock Syndrome- Caused by using tampons during period • ~Bacteria produce a toxic poison that affects liver and the immune system • Symptoms: vomiting, dizziness, rash, kidney and liver damage, diarrhea
Pap Smear- Test to detect for abnormal cells in cervix • Trichomoniasis- A vaginal infection that can lead to urethra and bladder infections • Vaginitis- Most common vaginal infection in women of childbearing age • Symptoms: Discharge, odor, itching, pain • Ovarian Cysts- Fluid-filled sacs on the ovary. Small non-cancerous, usually disappear on their own. Larger cysts may need surgery
Concerns continued… • Yeast Infection- Fungus, thick white cheesy discharge, foul odor, and severe itching • Sterility- Untreated STD, blockage of tubes, fertilization can not occur • Breast Cancer- Change in breast or nipple, lump or swelling in breast or armpit Self Exam should be performed once per month • Mammogram- X-ray of the breast to locate any mass or tumor. • Cervical Cancer- Causes can include many sexual partners, early sexual activity, effects women between 20-30
Preventing Problems • Prevent STD’s • Prevent vaginal irritation • Bathe regularly • Exercise regularly
Events Happened after Fertilization • Egg is fertilized in fallopian tubes • Fertilized ovum is carried to the uterus by • the beating cilia on the inner wall of oviduct • the contraction of muscles of fallopian tube • After reaching the uterus, the fertilized ovum fixed firmly onto the thick uterine wall----Implantation
Development of Human Foetus uterus foetus placenta umbilical cord amnion amniotic fluid Video on foetus development Click here
Functions of the Uterus • During embryo development • Protect the embryo • Provide a constant environment for the embryo to develop • Allow placenta to attach on • During birth of baby • Push the baby out by muscular contraction Click here
Functions of the Amniotic Fluid • To keep the foetus moist to prevent dessication • As a water cushion to • support the foetus • allow it to move freely • absorb shock • protect the foetus from mechanical injuries • To reduce temperature fluctuation • To lubricate the vagina during birth Click here
The Placenta oxygenated blood from mother’s artery deoxygenated blood to mother’s vein villus umbilical vein umbilical artery
Functions of the Placenta • As a place of exchange of materials between mother and the foetus • For secreting hormones
Adaptations of the Placenta • Finger-like villi • to increase the surface area for efficient diffusion • Maternal blood and foetal blood flows in opposite direction • to speed up diffusion of materials between them • Maternal blood capillaries and foetal blood capillaries are separated by thin membrane • to shorten the distance of diffusion of materials
Adaptations of the Placenta • Maternal blood is separated from foetal blood by capillary wall • to prevent high pressure of maternal blood to break the delicate foetal blood vessels • to prevent harmful substances to enter the foetus • to prevent clotting of maternal and foetal blood if their blood groups are incompatible Click here
The Birth Process • Onset of labour • Uterine muscles begin to make rhythmic contractions • Contractions gradually become stronger and closer
The Birth Process • Uterine contractions causes amnion to break and amniotic fluid to escape out of the vagina • Muscular contractions push the foetus head first through the vagina, and the umbilical cord is cut and tied • Further contractions push the placenta out of the body • “After birth” • Dilation of cervix allow the head of the foetus to pass through
Could you survive after birth without the care of your parents?
Parental Care • To increase the chance of survival of the young • Mother feeds milk to the baby • Milk provides the babies with a balanced diet • It also contains antibodies which defend the babies against infection
Birth Control • Human population increases exponentially • leads to storage of resources • problem of pollution becomes more serious • overcrowding
Using contraception methods What can we do?