Reproduction: How Life Continues

Comprehensive vocabulary flashcards covering the biological concepts, anatomical structures, reproductive processes, and scientific contributions featured in Chapter 11: Reproduction: How Life Continues.

Reproduction

A biological process by which living beings produce new individuals of their own kind, ensuring the continuation of life on Earth.

Asexual Reproduction

A mode of reproduction in which a single parent produces offspring that are almost exact, genetically identical copies of the parent.

Sexual Reproduction

A mode of reproduction involving two parents, where offspring inherit a mix of characteristics from both individuals, generating variation.

Vegetative Propagation

A form of asexual reproduction in plants where new individuals arise from vegetative or growing parts, such as roots, stems, or leaves, without producing seeds.

Cutting

An agricultural propagation technique in which a piece of a plant's shoot with nodes is cut and inserted into soil mixed with compost at an angle of about $45^{\circ}\text{–}60^{\circ}$ to grow into a new plant.

Grafting

A horticultural technique in which a stem cutting from one plant (Plant B) is inserted and fitted into a slit made in a healthy rooted plant (Plant A) and bound until they unite and grow together.

Layering

A vegetative propagation method where a flexible, thin twig of a parent plant is bent and buried under soil until roots develop after $10\text{–}15\,\text{days}$, after which it is cut from the parent to grow independently.

Plant Tissue Culture

A modern propagation technique where mass-produced, disease-free plantlets are grown from shoot tips (apical meristems) on nutrient media, eliminating viral infections and ensuring high yields.

Budding

An asexual reproduction method where repeated cell division at a specific site on the parent produces a small outgrowth (bud) that enlarges and detaches to live as an independent organism.

Spore Formation

An asexual reproductive method in which fungi produce huge numbers of tiny, lightweight, single-celled spores inside a sac or on a swollen vesicle that disperse via air currents to germinate in moist, warm conditions.

Clones

Offspring that are genetically identical to each other and to the parent organism, formed as a result of asexual reproduction mediated by mitosis.

Meiosis

A specialised type of cell division occurring in reproductive organs that reduces the chromosome number of a parent cell by half, creating haploid gametes and introducing genetic variation.

Gametes

Haploid reproductive cells produced by meiosis (sperm in males and eggs/ova in females) that fuse during fertilisation to re-establish the diploid chromosome number.

Sepal

The outermost green whorl of a flower that encloses and protects floral parts during the bud stage.

Petal

The brightly coloured, often fragrant inner whorl of a flower that enhances aesthetic appeal and functions to attract pollinators.

Stamen

The male reproductive organ of a flower, consisting of a slender filament and a pollen-producing anther at its tip.

Pistil

The female reproductive organ of a flower, consisting of a sticky terminal stigma, a long slender style, and a swollen basal ovary containing ovules.

Pollination

The transfer of pollen grains from the anther to the stigma of a flower, facilitated by agents such as wind, water, insects, or birds.

Self-Pollination

The transfer of pollen grains from an anther to the stigma of the exact same flower or another flower situated on the same plant.

Cross-Pollination

The transfer of pollen grains from the anther of a flower on one plant to the stigma of a flower on a different plant of the same species.

Fertilisation

The biological fusion of a male gamete with a female egg cell to form a single diploid cell known as a zygote.

Zygote

The single diploid cell resulting immediately from the successful fusion of male and female gametic nuclei, which subsequently develops into an embryo.

External Fertilisation

A reproductive strategy observed in many aquatic animals (such as frogs and most fish) where eggs and sperm are discharged into water, resulting in fusion outside the female body.

Internal Fertilisation

A reproductive process found in reptiles, birds, and mammals where sperm is deposited into the female reproductive tract, protecting gametes and allowing fertilisation inside the female body.

Testes

The paired oval male gonads situated within the scrotum that produce sperm and hormones responsible for puberty and sperm regulation.

Scrotum

An external sac of skin holding the testes outside the abdominal cavity to maintain a temperature slightly lower than core body temperature, required for sperm production.

Vas Deferens

A long muscular duct in the male reproductive system that conducts sperm from each testis to the urethra.

Ovaries

The paired female reproductive organs that house immature eggs from birth, produce and release one mature egg monthly after puberty, and secrete sex hormones.

Fallopian Tube

A slender duct connecting each ovary to the uterus through which the released egg travels and where fertilisation typically takes place.

Uterus

A hollow, bag-like muscular organ in the female pelvic cavity where a fertilised embryo implants into the vascular wall lining and develops into a foetus until birth.

Gametogenesis

The biological process of forming male and female haploid gametes through meiosis within the gonads (testes and ovaries).

Ovulation

The monthly release of a mature egg from one of the ovaries into the adjacent fallopian tube, occurring around Day 14 of a standard 28-day menstrual cycle.

Menstruation

The monthly breakdown and shedding of the thickened inner uterine lining and blood vessels through the vagina when an unfertilised egg degenerates, usually lasting 3 to 7 days.

Foetus

The developing human offspring inside the uterus from approximately the ninth week of pregnancy until delivery, characterized by the continued growth and maturation of formed organs.

In-Vitro Fertilisation (IVF)

A medical assisted-reproduction technique wherein an egg and sperm are combined outside the maternal body in a laboratory dish, after which the resulting embryo is transferred into the uterus.

P. Maheshwari

A prominent Indian botanist designated as the 'Father of Indian Embryology' who developed in-vitro fertilisation in flowering plants and authored 'An Introduction to the Embryology of Angiosperms' (1950).

Subhash Mukhopadhyay

The Kolkata physician and scientist who pioneered India's first test-tube baby, Kanupriya Agarwal (nicknamed Durga), via experimental IVF procedures in 1978.

Intra-Uterine Device (IUD)

A small contraceptive implement, such as a Copper-T, inserted by medical personnel into the uterine cavity to prevent pregnancy.