Human Reproduction PDF

LESSON 1 - WHAT IS REPRODUCTION? What is Reproduction? - For males, first ejaculation, Spermarche/Semenarche, occurs Human reproduction on average at age 13. Reproductive system...

LESSON 1 - WHAT IS REPRODUCTION? What is Reproduction? - For males, first ejaculation, Spermarche/Semenarche, occurs Human reproduction on average at age 13. Reproductive system Puberty Periods - Rapid matures - children who pass puberty in 2 years or less MALE FEMALE - Slow matures - children who pass Gonads Testis Ovary through puberty in 3-4 years to complete the transformation into Gametes Sperm Egg adults When will you know you are ready? 1. Prepubescent - this stage overlaps the closing year of childhood What is Puberty? - one is no longer a child, but not - Came from the Latin word yet an adolescent “pubertas” which means the “age - the secondary sex characteristics of manhood”. begin to appear but the - The process of physical changes reproductive organs are not yet through which a child’s body fully developed matures into an adult body capable of sexual reproduction. 2. Pubescent - this stage occurs at the dividing line between childhood When do changes happen? and adolescence; the time when the criteria of sexual maturation FEMALES appear. - Begin puberty around age 10 ½ and - secondary sex characteristics complete puberty at ages 15-17 continue to develop, and cells are - The landmark of puberty for produced in the sex organs females is Menarche, the beginning of the menstrual period around 12 3. Postpubescent - this stage overlaps ½ - 14 years old the first year of adolescence - secondary sex characteristics MALES become well-developed and sex - Generally, puberty begins at ages organs begin to function maturely. 11-12 and is completed at ages 16-17  What Causes these Changes Human Sexuality during Puberty? We are all sexual beings. Our sexuality affects who we are and - Hormones how we express ourselves as sexual beings. Sex hormones and their functions Sexuality is all about - Your body ESTROGENS - These are prevalent in - Your sex biological females. - Your gender - - Sexual activity - - Your sexual orientation - - Your sexual drives - - Your values, attitudes, beliefs and ideals about life, love - - Healthy relationships ANDROGENS - These are prevalent in biological males.  Sexuality refers to your total self  Gender - is the subjective result of the brain’s neurology within the context of society’s culture Gender orientation - subjective experience of a physical sex Gender identity - subjective experience of a cultural sex Gender expression - subjective experience of communicating gender orientation and identity Sexuality - Male or Female  Gender Identity: How we feel internally Gender Expression: How we demonstrate our gender Biological Sex: Sex assigned at birth Sexual Orientation: Who we are physically, spiritually, emotionally, and sexually attracted to  LESSON II: MALE REPRODUCTIVE SYSTEM Organs Functions Pathway of Sperm Objectives: 1. Identify the structures and major organs of the male reproductive system and describe their functions 2. Trace the pathway of the sperm cells in the organ system What is the male reproductive system? Male Reproductive System Consists of a number sex organs that are a part of the human reproductive process. Produces, stores and releases the male gametes, or sperm. *gametes- a sex cell Male Reproductive Organs External Genital Internal Genital Organs Organs 1. Penis 1. Testis 2. Scrotum 2. Epididymis 3. Vas deferens 4. Accessory Glands a. Seminal vesicles b. Prostate gland c. Bulbourethral glands Testis (plural testes) - The testes are the two- oval shaped male organs that produce sperm and hormone testosterone. Testosterone - the primary male sex hormone Vas Deferens (Ductus Deferens) - The vas deferens is a thin tube that starts from the epididymis to the urethra in the penis. - They transport sperm from the epididymis in anticipation of ejaculation. Each testis is made of tightly coiled structures called seminiferous tubules. Epididymis - The epididymis is a tightly coiled tubes against the testicles. - It acts as maturation and storage place for sperm. Vasectomy Prostate Gland - The Prostate Gland surrounds the ejaculatory ducts at the base of the urethra, just below the bladder. - The Prostate Gland is responsible for making the production of semen, a liquid mixture of sperm cells, prostate fluid and seminal fluid. Accessory glands a. Seminal Vesicles b. Prostate Gland c. Bulbourethral Glands - These glands produce nourishing fluids for the sperms that enter the urethra. Seminal Vesicles Bulbourethral Glands (Cowper's gland) - The Seminal Vesicles are sac-like - The Bulbourethral Glands are two structures attached to the vas small glands located on the sides of deferens at one side of the bladder. the urethra just below the prostate - They produce a sticky yellowish gland. fluid that contains fructose. - These glands produce a clear, slippery fluid that empties directly into the urethra.  External Genital Organs During orgasm, the semen is forcefully Penis expelled from the body by strong muscular Scrotum contractions of sperm ducts. Urethra - a tube within the penis that conveys semen out of the body during ejaculation. Glans - the rounded, highly sensitive head of the penis. Prepuce - a fold of skin, covering the head of the penis. Process: At the peak of sexual arousal, muscles in the epididymis, seminal vesicles, prostate gland, and vas deferens contract. At the same time, a sphincter muscle at the base. of the bladder contracts, preventing urine from leaking into the urethra from the bladder. Erectile Tissues Another sphincter also contracts, Corpus spongiosum - is the mass closing off the entrance of the of spongy tissue which surrounds urethra into the penis. urethra and involves in erection by allowing rushing of blood into it In the second stage of ejaculation, Corpus cavernosa - is one of a pair the expulsion stage, the sphincter at of sponge-like regions of erectile the base of the penis relaxes, tissue which contains most of the admitting semen into the penis. blood in the penis during penile Simultaneously, a series of strong erection muscle contractions around the base of the penis and along the urethra Ejaculation - is the discharge of semen expels the semen from the body. from the penis. Scrotum - A pouch of skin formed from the SPERMATOGENESIS lower part of the abdominal wall. - Spermatogenesis is the formation of - The scrotum keeps the testes at a sperm cells. temperature slightly cooler than - It takes place in the seminiferous body temperature. tubules. Sperm Function: To move and carry genetic information to the egg. Structure: - Head: The large head region of the sperm that contains DNA. - Midpiece: The narrow middle part of the cell that contains mitochondria. - Tail: The wavelike motion of the flagellum propels the sperm forward. Process: Diploid cells that begin the process are located near the outer wall of the tubules. - These cells multiply constantly by mitosis, and each day about 3 million of them differentiate into primary spermatocytes, the cells that undergo meiosis.  Meiosis I of a primary spermatocyte produces secondary spermatocytes, each with the haploid number of chromosomes (n=23). - The cells are still in their duplicated state, each consisting of two identical chromatids. Meiosis II then forms four cells, each with the haploid number of single-chromatid chromosomes. A sperm cell develops by differentiation of each of these haploid cells and gradually pushed toward the center of the seminiferous tubule. - From there, it passes into the epididymis, where it matures, becomes motile, and is stored until ejaculation. - Mitochondria is located in the midpiece of the sperm cell. - Epididymis of the human male does mature sperm stored for a time - Correct order of travel of sperm: Testis - Epididymis - Vas deferens - Urethra  LESSON III: FEMALE Labia REPRODUCTIVE SYSTEM - Rich in nerve endings and blood vessels Functions of female reproductive - Protects internal organs against system pathogens Formation of ova - Functions in sexual arousal Reception of spermatozoa Provision of suitable environment for fertilization and fetal development Parturition Lactation, the production of breast milk, which provides complete nourishment for the baby in its early life. EXTERNAL GENITALIA (VULVA) Labia majora - Has two folds of adipose tissue that border each side of the vagina. - The labia majora enclose and protect the other external reproductive organs. - Literally translated as "large lips," Mons Pubis - A region of adipose tissue the labia majora are relatively large above the vagina that is covered with hair. and fleshy - It contain sebaceous glands. After puberty, the labia majora are covered with hair. Labia minora Clitoris - The labia minora are smaller folds - It is small cylindrical erectile body (forchette) of skin that lie inside the - Measuring about 1.5 to 2cm labia majora. - Situated in the most anterior part of - Contains no hair follicles or sweat the vulva glands. - The two labia minora meet at the - The folds contain connective clitoris tissues,numerous sebaceous gland, - A small, sensitive protrusion. erectile muscle fibers and numerous - The clitoris is covered by a fold of vessels and nerve endings skin, called the prepuce, richly supplied with nerves. - The clitoris is very sensitive to stimulation and can become erect. Vestibule - The vestibule is formed by the labia minora - It encloses: Urethral opening Urethral opening - Situated in midline just infront of Vaginal orifice and hymen the vaginal orifice Ducts from the greater vestibular - About 1-1.5 cm below the pubic arch Vaginal orifice and hymen Organ of copulation and forms the - Lies in the posterior end of the birth canal of parturition vestibule - It completely enclosed by a septum of mucous membrane called hymen - Hymen Located just inside the vaginal opening - No known function; not always present - It is usually ruptured at the consummation of marriage - The cervix is the lower part of the uterus, which protrudes into the upper part of the vagina. It can be seen during a pelvic examination. Like the vagina, the cervix is lined with a mucous membrane, but the mucous membrane of the cervix is smooth. - Sperm can enter and menstrual INTERNAL GENITALIA blood can exit the uterus through a (REPRODUCTIVE TRACT) channel in the cervix (cervical canal). Vagina = "birth canal" A tube like, muscular but elastic organ About 4 to 5 inches long in an adult woman. PH-4 acidic It is the passageway for sperm to the egg and for menstrual bleeding  - The cervical canal is usually narrow, but during labor, the canal widens to let the baby through. - The cervix is usually a good barrier against bacteria, except around the time an egg is released by the ovaries (ovulation), during the menstrual period, or during labor. - The main function of the uterus is to sustain a developing fetus. MYOMETRIUM - It prepare for this possibility for - Muscular, supports fetus, contracts each month at birth and to shed the - At termination of pregnancy it endometrium during menstruation expels the uterine contents - The uterus consists of the cervix and the main body (corpus). PERIMETRIUM ENDOMETRIUM - Is a serous membrane that line the - Inner lining of uterus, nourishes outside of the uterus developing embryo, built up each month for pregnancy, if not, shed during menstruation  - It's dome-shaped and sits at the top of the uterus. Like the cervix, the uterine fundus is important in reproductive health, too. Not only does the fundus help balance appropriate hormones during pregnancy, it also aids in protection of the fetus. ISTHMUS - A tiny channel that connects the ampulla to the portion of your fallopian tube that's closest to your uterus - The uterine isthmus can become more compressible and soft in pregnancy, which is a finding known as Hegar's sign. Fallopian tubes [uterine tubes] - It typically presents between the - Stretch from the uterus to the fourth and sixth week of pregnancy ovaries and measure about 8 to 13 and may be present until the 12th cm in length. week of pregnancy - The ends of the fallopian tubes lying next to the ovaries feather into ends called fimbria - Millions of tiny hair-like cilia line the fimbria and interior of the fallopian tubes. - The cilia beat in waves hundreds of times a second catching the egg at ovulation and moving it through the tube to the uterine cavity. - Fertilization typically occurs in the fallopian tube AMPULLA they sweep a newly released egg from your - The major channel in your ovaries into your fallopian tubes. Damaged fallopian tube, located in-between fimbriae can negatively impact your fertility the infundibulum and the isthmus. - Fertilization most often takes place in the ampulla. - They produce and store your eggs (also called ovum) and make - The infundibulum catches and hormones (estrogen & channels the released eggs; it is the progesterone) that control your wide distal (outermost) portion of menstrual cycle and pregnancy. each fallopian tube. During ovulation, one of your ovaries releases an egg - Your fimbriae are finger-like projections at the ends of each of your OOGENESIS & FOLLICULOGENESIS fallopian tubes. Each month, - Oogenesis is the process of formation of female gametes. This process begins inside the fetus before THE MENSTRUAL CYCLE birth. The steps in oogenesis up to the - The menstrual cycle is a natural but production of primary oocytes occur before complex cycle of changes that your birth. Primary oocytes do not divide further. body goes through each month. They either become secondary oocytes or - A menstrual cycle is measured from degenerate (atresia). the first day of your period to the - The goal of folliculogenesis is to day before your next period. produce a single dominant follicle - The average length of a menstrual from a pool of growing follicles. cycle is 28 days, but everyone's cycle is different. For example, \\ teenagers might have cycles that last 45 days, whereas people in their 20s to 30s might have cycles that last 21 to 38 days. PHASES OF MENSTRUAL CYCLE 1. Your period (menstruation) - When you have a period, your uterus lining sheds and flows out of your vagina. Your period contains blood, mucus and some cells from the lining of your uterus. The average length of a period is 3 to 7 days. 2. The follicular phase - The follicular phase starts on the first day of your period and lasts for 13 to 14 days. Changing hormone levels cause the lining of your uterus to thicken and follicles to grow on the surface of the ovaries. Usually only one follicle will mature into an egg 3. Ovulation - Ovulation is when a mature egg is released from an ovary. This usually happens once a month, about 2 weeks before your next period.  You're most likely to get pregnant if you have unprotected sex around the time of ovulation. 4. The luteal phase - After ovulation, the egg travels through the fallopian tubes to your uterus. The uterus lining continues to thicken in preparation for pregnancy. WHAT CAUSES PCOS? - If you fall pregnant, you won't have Experts don't know the exact cause of a period. If you don't get pregnant, PCOS. you'll have a period and the Many women with PCOS have insulin menstrual cycle will start again. resistance. This means the body can't use insulin well. WHAT IS POLYCYSTIC OVARY Insulin levels build up in the body and SYNDROME (PCOS)? may cause higher androgen levels. Polycystic ovary syndrome (PCOS) is a Obesity can also increase insulin levels set of symptoms caused by a problem with a and make PCOS symptoms worse. woman’s hormones. It affects the ovaries. PCOS is a very common condition in WHO IS AT RISK FOR PCOS? women of childbearing age. In some cases, You may be more likely to have PCOS if it can lead to serious health issues if not your mother or sister has it. You may also treated. be more likely to have it if you have insulin Treatment for PCOS is often done with resistance or are obese. medicine. This can’t cure PCOS, but it Women with PCOS are more likely to helps reduce symptoms and prevent some develop certain serious health problems. health problems. These include type 2 diabetes, high blood In some cases, a woman doesn’t make pressure, problems with the heart and blood enough of the hormones needed to ovulate. vessels, and uterine cancer. Women with When ovulation doesn’t happen, the PCOS often have problems with their ovaries can develop many small fluid-filled ability to get pregnant (fertility). sacs (cysts). These cysts make hormones called androgens. WHAT ARE THE SYMPTOMS OF Androgens are a type of hormone PCOS? normally found in abundance in men, but Missed periods, irregular periods, or very women normally have them in smaller light periods amounts. Women with PCOS often have Ovaries that are large or have many cysts high levels of androgens. Extra body hair, including the chest, This can cause more problems with a stomach, and back (hirsutism) woman’s menstrual cycle. And it can cause Weight gain, especially around the belly many of the symptoms of PCOS. Acne or oily skin Male-pattern baldness or thinning hair  Infertility more efficiently, lower blood glucose levels, Small pieces of extra skin on the neck or and may help you ovulate. armpits (skin tags) Medicines to treat other symptoms. Some Dark or thick skin patches on the back of medicines can help reduce hair the neck, in the armpits, and under the growth or acne breasts ACCESORY REPRODUCTIVE HOW IS PCOS TREATED? ORGANS If you do plan to become pregnant, your - The breasts contain mammary treatment may include: glands. Only the mammary glands A change in diet and activity. A healthy in women can produce milk to feed diet and more physical activity can help you a baby during LACTATION. For lose weight and reduce your symptoms. this reason, the breasts are They can also help your body use insulin accessory organs of the female more efficiently, lower blood glucose levels, reproductive system. and may help you ovulate. - Breasts are secondary sexual Medicines to cause ovulation. Medicines characteristics, not organs. can help the ovaries to release eggs normally. These medicines also have certain risks. They can increase the chance of a multiple birth (twins or more). And they can cause ovarian hyper stimulation. This is when the ovaries release too many hormones. It can cause symptoms, such as belly bloating and pelvic pain. HOW IS PCOS TREATED? If you don't plan to become pregnant, your treatment may include: Birth control pills. These help to control menstrual cycles, lower androgen levels, and reduce acne. Diabetes medicine. This is often used to lower insulin resistance in PCOS. It may also help reduce androgen levels, slow hair growth, and help you ovulate more regularly. A change in diet and activity. A healthy diet and more physical activity can help you lose weight and reduce your symptoms. They can also help your body use insulin