reproduction

Sexual Reproduction

The production of offspring through the fusion of two gametes to form a zygote.

Gametes

Haploid sex cells (sperm and egg) involved in sexual reproduction.

Fertilization

The fusion of gametes.

Zygote

The diploid cell formed by fertilization, containing the full complement of chromosomes.

Development

The process where a zygote undergoes cell division and differentiation to become an embryo.

Asexual Reproduction

Generating offspring without the fusion of egg and sperm.

Budding

A form of asexual reproduction where a new individual grows from an outgrowth of the parent.

Regeneration

The ability to regrow lost body parts, which can lead to the formation of new individuals.

Parthenogenesis

Development of an embryo from an unfertilized egg.

Fission

The separation of a parent organism into two or more similar sized individuals.

Hydra

A type of cnidarian that reproduces asexually via budding.

Rapid Population Growth

An advantage of asexual reproduction that allows for the quick generation of many offspring.

Genetic Variation

The diversity in gene frequencies, which is increased through sexual reproduction.

External Fertilization

Gametes are released into the environment, where fertilization occurs outside the body.

Internal Fertilization

Sperm are introduced directly into the female reproductive tract for fertilization.

Oviparity

A reproductive strategy where embryos develop externally after egg-laying.

Ovoviviparity

Internal fertilization occurs, and fertilized eggs remain inside the mother's body until hatching.

Viviparity

Internal fertilization occurs, and embryonic development happens within the mother's body.

Gonads

The primary reproductive organs responsible for the production of gametes.

Testes

Male gonads responsible for sperm production and hormone production.

Scrotum

The sac that houses the testes outside the abdominal cavity to regulate temperature.

Accessory Glands

Glands that produce fluids to aid in sperm movement and nourishment.

Semen

The fluid that contains sperm and is ejaculated during reproduction.

Sertoli Cells

Support and nourish developing sperm cells in the testes.

Leydig Cells

Cells that produce testosterone in the testes.

Inhibin

A hormone produced by Sertoli cells that provides negative feedback to regulate sperm production.

Oogonia

Diploid stem cells in females that undergo mitosis to generate primary oocytes.

Primary Oocyte

A diploid cell that begins meiosis but arrests in prophase I until triggered by hormones.

Secondary Oocyte

A haploid cell formed after the completion of meiosis I; it arrests in metaphase II until fertilization.

Polar Body

A small cell produced during oogenesis that typically degenerates.

Menstrual Cycle

The monthly changes in female hormone levels and reproductive organ structure.

Estradiol

The predominant form of estrogen in humans.

Corpus Luteum

Remnant of the follicle post-ovulation that produces progesterone.

Human Sexual Response Cycle

Characterized by four phases: excitement, plateau, orgasm, and resolution.

Cleavage

Rapid mitotic divisions in early embryonic development that leads to the formation of blastomeres.

Blastocyst

The stage of embryonic development that develops a fluid-filled cavity and consists of trophoblast and inner cell mass.

Implantation

The process by which the blastocyst attaches to the uterine wall.

Placenta

An organ that develops during pregnancy, facilitating nutrient and gas exchange between mother and fetus.

Erythroblastosis Fetalis

A condition that can occur due to Rh incompatibility between the mother and fetus.

Hormonal Feedback

Mechanisms by which hormonal levels regulate themselves to maintain homeostasis.

Vasectomy

A surgical procedure for male sterilization that prevents sperm from being released during ejaculation.

Contraceptive Methods

Various strategies used to prevent pregnancy during sexual intercourse.

Menopause

The cessation of menstruation and ovulation, marking the end of a female's reproductive years.

Oxytocin

A hormone that stimulates uterine contractions during labor.

Prostaglandins

Hormones that facilitate uterine contractions and are influenced by estradiol.

Fertilization Timing

The critical period around ovulation when sperm must encounter the egg for impregnation.

Sperm Capacitation

The process sperm undergo to gain the ability to fertilize an egg.

Polyspermy Prevention

Mechanisms that prevent more than one sperm from fertilizing an egg, such as fast and slow blocks.