Understanding Human Reproductive Processes and Health

Posted on May 12, 2025 in Biology

FUNCTION.REPRO – GAMETOGENESIS: Gametes are formed in gonads.

Fertilization

: Internal joining of two gametes forms the zygote.

Embryo Development

: The zygote undergoes cell division until it becomes an embryo that continues developing into a fetus.

Childbirth

: The baby is born alive and fully formed.

Development

: The baby grows and reaches maturity (adulthood).

Changes at Sexual Maturity

– Primary Sex Characteristics:

Puberty

: For people to reproduce, organs must mature (ages of 10 to 16).

Sex Hormones

: Reproductive organs produce them; these hormones cause secondary sex characteristics. Adolescence: From puberty to adulthood, physical maturity, psychological and social changes, and sexual desire appear.

Fertilization

– The union of a sperm and an ovum forms a zygote. Ovulation and sexual intercourse are needed during the 24-48 hours after ovulation. Sperm can survive from 3 to 5 days inside. Sperm penetrate the covering of the ovum, and a fertilizing membrane is produced to prevent other sperm from entering. The zygote moves towards the uterus. The corpus luteum continues to release progesterone, maintaining the thick walls of the endometrium and preventing menstruation. The zygote divides and becomes a mass of cells called morula. The morula evolves and is transformed into a blastocyst, which implants in the endometrium six or seven days after fertilization.

Stages of Pregnancy

– The blastocyst develops to become an embryo. Placenta: An organ with many blood vessels that enables nutrients to pass from the mother’s blood to the fetus. Waste substances produced are passed to the mother. Umbilical cord. Amniotic sac.

Infertility

– Lack of ovulation, problems in the uterus that prevent the embryo from implanting, obstruction in the fallopian tubes, low sperm count, immature or malformed sperm, incompatibility of sperm with the vaginal mucus, and obstruction in the vas deferens.

Artificial Insemination/In Vitro Fertilization

Birth Control Methods

– Natural: Symptoms-based, calendar-based, coitus interruptus. Artificial: (barrier) Male condom, female condom, diaphragm, intrauterine device (IUD), contraceptive pills, patches, vaginal rings, hormonal IUDs, spermicides. Surgical: Tubal ligation, vasectomy.

Sexually Transmitted Diseases

– Syphilis: Treponema pallidum (bacterial). Gonorrhea: Neisseria gonorrhoeae (bacterial). Genital Herpes: Simple herpes (viral). Hepatitis: A, B, C (viral). Human Papillomavirus: (viral). AIDS: HIV (viral). Vaginal Thrush: (fungal).



Health and Disease

– When a healthy person is not suffering from a disease. Physical: General condition of the body. Mental: The way a person feels, thinks, and deals with life. Social: State in which basic human needs are met. What is a Disease? A change in the body that produces a loss of health. Aetiology/Symptom/Sign.

Transmission of Infectious Diseases

– Agent: Pathogen that causes a disease. Reservoir: Where the pathogen lives and reproduces. Vector: Microorganism that carries and transmits the pathogen. Host: Organism infected.

Transmission of Pathogens

– Direct Contact: Person to person touching. Indirect Contact: Transmission by vehicle, vector, or through air.

The Immune System

– Surface Barriers: Physical barriers that protect the body. Chemical substances that prevent the growth of bacteria. Biological: Bacteria that live on or inside the body.

Non-Specific Immune Response

– A pathogen crosses the surface barriers and is activated, with phagocytes performing the same response for all pathogens.