Methods of Reproduction and Human Development

This set of flashcards covers the vocabulary regarding sexual and asexual reproduction, human reproductive anatomy, and plant reproductive structures as discussed in the lecture notes.

Reproduction

A process that always produces an offspring through either sexual or asexual means.

Sexual reproduction

A method commonly used by plants and animals where offspring are produced with two parents, involving the combination of female and male gametes.

DNA

Instructions that determine an organism’s traits and how it functions, passed on during reproduction.

Gametes

Cells that form in reproductive organs and contain half the genetic information needed to make an individual.

Sperm

Male gametes that are usually small, streamlined, and possess a long flagellum for movement.

Flagellum

A long tail on a sperm cell that helps it move through the female reproductive tract.

Eggs

Female gametes that are generally larger and immobile, providing protection, nutrients, and instructions for offspring growth.

Fertilization

The process by which two gametes, one female and one male, combine to form a single cell.

Zygote

The single complete cell formed by fertilization that eventually divides to develop into a unique independent organism.

Asexual reproduction

A process commonly used by bacteria, some fungi, and some plants that uses only one parent and produces clones.

Clones

Offspring produced through asexual reproduction that are genetically identical to the parent.

Budding

A type of asexual reproduction where a new organism grows as a small outgrowth or bud on the parent until it detaches.

Binary fission

A type of asexual reproduction where one cell divides into two identical cells.

Fragmentation

A type of asexual reproduction where an organism breaks into pieces, and each piece grows into a new, identical organism.

Parthenogenesis

A type of asexual reproduction where an egg develops into a new organism without being fertilised.

Internal fertilisation

A process where gametes fuse inside a body, typically occurring in terrestrial environments and resulting in a small number of offspring.

External fertilisation

A process where gametes fuse outside the body, requiring less parental energy but resulting in a low individual success rate and thousands of gametes released.

Mate

An animal’s partner during the process of sexual reproduction.

Migration

The movement of members of a species to a different environment, often timed with external fertilisation.

External triggers

Environmental factors, such as temperature, that can time the process of external fertilisation.

Embryo

The stage of development where the initial zygote has developed into a ball of cells.

Fetus

The stage of development where an embryo develops specialized structures such as organs and fully formed hands.

Internal development

A process where young develop inside the parent's body, providing a higher chance of survival but using significant parental energy.

Pregnancy (gestation)

The period of development inside the body from fertilisation until birth.

Predation

The risk of being hunted, which increases for a parent during internal development due to fatigue.

External development

A process seen in smaller animals that lay many eggs with a low survival rate, often left alone during incubation.

Terrestrial eggs

Eggs laid on land that are usually hard-shelled and contain all required nutrients inside.

Aquatic eggs

Eggs laid in water, covered in a jelly-like substance that allows nutrients to flow in and out.

Incubation

The process of development that occurs outside the body.

Hormones

Chemicals that stimulate specific organs or cells into action, such as triggering changes during development.

Gonad

An organ that produces gametes, specifically the testes or ovaries.

Oestrogen

A hormone involved in the development of female characteristics and reproductive organs.

Testosterone

A hormone involved in the development of male characteristics and reproductive organs.

Vas deferens

A reproductive organ that provides a pathway for sperm to reach the penis.

Prostate

An organ that produces the fluid (seminal fluid) used to transport sperm.

Seminal fluid (semen)

The fluid produced by the prostate that carries sperm.

Penis

The male organ that carries seminal fluid and deposits it in the vagina.

Testes

The male gonads that produce sperm.

Fallopian tubes

The pathway that allows the movement of an egg from the ovary to the uterus.

Uterus

The internal environment where a fetus develops.

Ovaries

The female gonads that produce and store eggs.

Endometrium

The lining of the uterus that allows for the implantation of a zygote.

Cervix

The structure that connects the uterus to the vagina.

Vagina

The passage connecting the uterus and cervix to the outside of the body.

Puberty

A period where the body undergoes physical changes to reach sexual maturity.

Ovulation

The release of a mature egg from an ovary, which typically occurs once a month and lasts about $24\,\text{hours}$.

Menstruation

The shedding of the uterine lining (a period) that occurs if an egg is not fertilised.

Placenta

An organ that forms when an embryo attaches to the endometrium, connecting the mother to the fetus via the umbilical cord.

Trimester

A three-month division of the human gestation period, which lasts a total of $9\,\text{months}$.

Stamen

The male reproductive system of a plant, consisting of the anther and filament.