Asexual Reproduction

• Reproduction is a biological process where organisms create new individuals.
• Reproduction is essential for species continuation via DNA replication, but not for individual survival.
• DNA copying during reproduction maintains species characteristics and allows for variations that aid in evolution and survival.

Asexual Reproduction

• In asexual reproduction, a single parent produces genetically identical offspring without gametes
• This process is common in unicellular organisms, fungi, and some plants.

Types of Asexual Reproduction

• Binary Fission: A single cell divides into two identical cells (e.g., Amoeba, Leishmania).
• Multiple Fission: A parent cell divides into many daughter cells simultaneously (e.g., Plasmodium).
• Budding: A bud forms and detaches from the parent to grow into a new individual (e.g., Yeast, Hydra).
• Fragmentation: An organism breaks into fragments, each growing into a new individual (e.g., Spirogyra).
• Regeneration: Lost body parts can regrow into a complete organism (e.g., Planaria, Hydra).
• Vegetative Propagation: New plants grow from roots, stems, or leaves (e.g., Bryophyllum, Potato), used for plants that don't produce seeds like banana, sugarcane, rose, and jasmine.
• Spore Formation: Spores germinate under favorable conditions to form new organisms (e.g., Rhizopus, Fungi).

Sexual Reproduction

• Sexual reproduction involves two parents and the fusion of gametes.
• This leads to genetic variation, contributing to evolution; gametes (sperm and egg) are haploid.

Sexual Reproduction in Plants

• Stamen (male) produces pollen grains.
• Pistil (female) contains the ovary, ovules, stigma, and style.
• Pollination is the transfer of pollen from stamen to pistil, either self-pollination (same flower) or cross-pollination (another flower via wind, water, or insects).
• Fertilization occurs when pollen fuses with the ovule to form a zygote.
• The zygote develops into an embryo, then a seed, and finally a new plant through germination.

Male Reproductive System

• Testes produce sperm and testosterone.
• The scrotum maintains a lower temperature for sperm production.
• The vas deferens carries sperm.
• Seminal vesicles and the prostate gland secrete fluids for sperm mobility.
• The urethra serves as a common passage for urine and sperm.
• The penis delivers sperm into the female body.

Female Reproductive System

• Ovaries produce eggs and female hormones.
• The fallopian tube (oviduct) is the site of fertilization.
• The uterus is where the embryo implants and grows.
• The cervix is the opening between the uterus and vagina.
• The vagina receives sperm during intercourse.

Fertilization and Pregnancy

• Fertilization is the fusion of sperm and egg in the fallopian tube, creating a zygote.
• The zygote divides to form an embryo, which implants in the uterus.
• The placenta provides oxygen and nutrients from mother to baby.
• Gestation (pregnancy period) lasts approximately 9 months.

Menstrual Cycle

• If the egg is not fertilized, the uterus lining sheds, leading to menstruation (lasting 3-7 days).
• This cycle repeats approximately every 28 days.

Reproductive Health and Contraception

• Reproductive health ensures safe pregnancy and prevents STDs.
• Sexually Transmitted Diseases (STDs) can be bacterial (Gonorrhea, Syphilis) or viral (HIV/AIDS, Genital warts).

Contraceptive Methods

• Barrier Methods: Condoms, diaphragm (prevent sperm entry).
• Hormonal Methods: Pills, injections (prevent ovulation).
• IUDs (Copper-T, Loop): Prevent implantation.
• Surgical Methods: Vasectomy (males), Tubectomy (females).

Asexual reproduction involves a single parent producing genetically identical offspring. Common in unicellular organisms, fungi, and some plants, it includes binary fission, multiple fission, budding and fragmentation. Each method enables efficient propagation without genetic variation.