Sexual Reproduction in Humans PDF

SEXUAL REPRODUCTIO N IN HUMAN  SEXUAL REPRODUCTION Adolescence- stage that humans become capable of taking part in the reproductive process. At this stage, our reproductive organs undergo changes to be able to produce mature sex cells. Chromosomes- contain the genetic information which c...

SEXUAL REPRODUCTIO N IN HUMAN  SEXUAL REPRODUCTION Adolescence- stage that humans become capable of taking part in the reproductive process. At this stage, our reproductive organs undergo changes to be able to produce mature sex cells. Chromosomes- contain the genetic information which carries unique inherited traits. CHROMOSOMES SEXUAL REPRODUCTION Zygote- fertilized egg that contain 46 chromosomes The purpose of sex is to merge two sets of genetic information to create offspring that is genetically different from their parent. ZYGOTE MALE REPRODUCTIVE SYSTEM Male reproductive system- produces sperm cells and delivers them inside the female reproductive system. Testes- Primary male reproductive organ Oval shaped organ found inside a protective sac of skin called scrotum  MALE REPRODUCTIVE SYSTEM Seminiferous tubules- compartments with tiny coiled tubes It is where the sperm cell produced through cell division called meiosis. TESTES  HORMONES Luteinizing Hormone – stimulates the secretion of the sex hormone testosterone. Follicle-stimulating hormone- together with testosterone, it stimulates the production of sperm cell. Testosterone- responsible for the secondary characteristics of male such as deepening of voice, growth of  TESTES Epididymis A tube where the sperm cell will mature until they are capable of swimming and moving. Most of the sperm is stored Vas deferens Urethra- It is a tube where the semen exit from the body. The same tube which urine passes and exists the body MALE REPRODUCTIVE SYSTEM  HUMAN SPERM CELL Head- contain little cytoplasm that contain the chromosomes and the nucleus covered by cap called acrosome which stores the enzymes needed by the sperm to penetrate an egg cell during fertilization. Midpiece- contains mitochondria that supply the energy needed to propel the sperm through the female reproductive system Tail- flagellum that whips enabling it to move. SPERM CELL Semen- mixture of fluids and sperm cell Prostate Gland- produce alkaline fluid that neutralizes the acids in the female reproductive system Seminal vesicle- Fluids rich in sugars that sperm cells use for energy. Bulbourethral glands- alkaline fluids that neutralizes traces of acidic urine in the urethra. Penis- the male organ that deposits the sperm in the female reproductive system during sexual intercourse or copulation. During sexual excitement, blood rushes into the penis, making it rigid and erect. Ejaculation- a process of forceful expulsion of the semen from urethra. 3.5 mL semen about 300-400 FEMALE REPRODUCTIVE SYSTEM Ovaries- female reproductive structure responsible for producing eggs. Estrogen- hormone that triggers the development of secondary characteristic s of female such as widening of hips and enlargement of the breast and it stimulates egg production. 11-14 Years old- onset of mature egg cell production. Menarche- first discharge of blood from the vagina FEMALE REPRODUCTIVE SYSTEM Pregnancy- Nourishing and protecting the fertilized egg during nine months of development. At birth, all females are born with all the 2 million egg cells they will ever produce. At puberty stage the egg cell will gone down to about 400,000 300-500 eggs are capable of maturing to become an Ova FEMALE REPRODUCTIVE SYSTEM Cilia- hairlike structure that sweep the ovum from the ovary into either of the fallopian tube. Fallopian tube- is the passageway through which ovum moves from the ovary to the uterus Vagina- a passageway that leads from the outside of the female’s body to the entrance of the uterus called cervix Uterus- hollow muscular organ where the zygote implanted. FEMALE REPRODUCTIVE CYCLE Ovarian cycle/ Menstruation- monthly changes in the ovary as it prepares the egg for maturation Ovaries prepare the female body for a possible pregnancy each month in a series of events. 28 days- span of ovarian cycle  STAGES OF OVARIAN CYCLE Follicular Phase Follicle- is a cluster of cells that surrounds an immature egg cell and provides it with nutrients. The anterior pituitary gland releases the Follicle stimulating hormone and Leuteinizing hormone into the bloodstream. FSH and LH produce estrogen, a hormone that aids the growth of follicle. Follicle burst  STAGES OF OVARIAN CYCLE Luteal Phase LH causes the cell of the ruptured follicle to grow, forming a corpus luteum. Corpus Luteum- yellowish mass of follicular cells functions like an endocrine gland that secretes Progesterone. Progesterone- hormones that signals the body to prepare for fertilization MENSTRUAL CYCLE STAGES OF HUMAN DEVELOPMENT BEFORE BIRTH 1.Fertilization- union of sperm cell and egg cell that contains 23 chromosomes. Blastocytes- a small cells when the zygote undergo cell division. Implantation- when the blastocytes attaches itself to the uterine wall. Embryo STAGES OF HUMAN DEVELOPMENT BEFORE BIRTH 2. Embryonic development Embryo- term refer to a baby in its first two months inside the mother’s womb. Villi- produces by uterine wall which constitute the placenta along with other blood vessels. Umbilical cord- Connects the placenta to the embryo Amniotic sac- formed during the third week of pregnancy that contains amniotic fluid which helps cushion and protects the STAGES OF HUMAN DEVELOPMENT BEFORE BIRTH 3. Fetal Development During third month,; eyes, fingers, toes, arms and legs are formed (Fetus) Fetal heart can be heard beating Mother can feel the movement of the fetus Thumb suck  STAGES OF HUMAN DEVELOPMENT BEFORE BIRTH 4. Birth By the ninth month, the fetus has usually rotated to a head down position inside the uterus Labor- the muscular contraction of the uterus.  SEXUALLY TRANSMITTED DISEASE Syphilis- caused by bacterium Treponema pallidum. Chancre- a painless sore in the genital area, rectum or mouth which where infections developed. The second stage is characterized by fever and skin rashes. Neural lesion that can damage the nervous system leading to paralysis, insanity and death Penicillin  SEXUALLY TRANSMITTED DISEASE Gonorrhea- caused by Neisseria gonorrhoeae which invades the epithelial lining of the vagina and male urethra. Pus- discharge caused by gonorrhea Burning sensation during urination, pain and swelling of the testicles Vaginal bleeding in between periods, abdominal and pelvic pain Antibiotics  SEXUALLY TRANSMITTED DISEASE Genital Herpes-caused by simplex virus 2 Painful, itching lesions and blister in the genital area Incurable  SEXUALLY TRANSMITTED DISEASE Acquired immunodeficiency syndrome- caused by human immunodeficiency virus. No cure available AIDS is transmitted through contact with body fluids containing the virus, sexual intercourse, sharing of needles, blood transfusion and at birth from infected mother. 5-10 years before it will be a full blown disease  SEXUALLY TRANSMITTED DISEASE Weight loss, diarrhea, swollen lymph glands, low grade fever, fatigue and night sweat. Susceptible in infections  BIRTH CONTROL Abstinence No semen enters the vagina It is free and is the only sure way not to get pregnant It prevents sexually transmitted infections Difficulty in practicing CONTRACEPTIVE CONTROL PILLS Stop ovaries from releasing eggs. One must get them from a doctor Very effective if used correctly Does not Prevent STI’s  INTRAUTERINE DEVICE The doctor puts it in the uterus to stop sperm from joining with the egg. Must be inserted by a health care provider Effective, no need to remember it since it is always in place. Does not prevent STI’s can be dislodge  CONDOM Rubber placed over the penis or in the vagina to block egg and sperm from mixing Prevents STI’s if used correctly Readily available at the store Very effective if used correctly  DIAPHRAGM A small cup covers the opening of the uterus to stop sperm from entering. Used with spermicidal foams and creams, must be fitted by a health care provider Effective if used correctly Does not prevent STI’s  SPERMICIDAL FOAMS AND CREAMS Placed in the vagina before intercourse to kill sperm Readily available in the stores Not very effective at preventing pregnancy Does not prevent STI’s VASECTOMY/ TUBAL LIGATION A medical procedure that permanently stops sperm from reaching eggs. Extremely effective in preventing pregnancy Does not prevent STI’s