Biology: Reproduction in Organisms

These vocabulary flashcards cover the fundamental concepts of reproduction, including asexual and sexual methods, plant propagation, and the developmental cycles of diverse organisms as presented in the introductory biology curriculum.

Reproduction

A biological process through which an organism produces offspring similar to itself, ensuring the continuity of the species across generations.

Life Span

The specific duration from an organism's birth to its natural death, which varies greatly across different species regardless of their physical size.

Panchanan Maheshwari

A renowned botanist ($1904-1966$) who specialized in plant embryology and tissue culture, and led the development of the first NCERT biology textbooks in $1964$.

Asexual Reproduction

A mode of reproduction where a single parent produces offspring that are genetically and morphologically identical to itself.

Clone

A term used to describe a group of individuals that are exact genetic and morphological copies of a single parent.

Binary Fission

A type of asexual reproduction common in single-celled organisms like Amoeba where a cell divides into two equal halves that grow into adults.

Encystation

The process by which an organism like Amoeba secretes a protective three-layered hard wall around itself during unfavorable environmental conditions.

Sporulation

The phenomenon where an encysted organism undergoes multiple fission to release numerous minute spores once favorable conditions return.

Vegetative Propagules

Units of vegetative propagation in plants, such as runners, rhizomes, tubers, and offsets, that are capable of forming new offspring.

Terror of Bengal

A name given to the invasive aquatic plant water hyacinth, which spreads rapidly through offsets and depletes oxygen levels in water bodies.

Juvenile Phase

A period of growth and physical maturity that all organisms must undergo before they are capable of reproducing sexually.

Strobilanthus kunthiana

Also known as neelakuranji, this plant is notable for its rare flowering cycle which occurs only once every $12$ years.

Oestrus Cycle

The cyclical physiological changes observed in non-primate mammals during their reproductive phase.

Menstrual Cycle

The reproductive cycle occurring in primates, such as monkeys, apes, and human beings.

Gametogenesis

The process of forming haploid ($n$) male and female gametes.

Homogametes

Gametes that are morphologically similar and cannot be categorized into distinct male and female types, often found in certain algae.

Meiocytes

Specialized diploid ($2n$) cells in diploid organisms that undergo meiosis to produce haploid ($n$) gametes.

Parthenogenesis

A reproductive process where a female gamete develops into a new organism without the occurrence of fertilization.

Syngamy

The fusion of male and female gametes resulting in the formation of a diploid ($2n$) zygote.

Embryogenesis

The developmental stage where a zygote transforms into an embryo through cell division and specialization.

Oviparous

Animals that lay eggs covered by hard calcareous shells, with development occurring outside the parent's body.

Viviparous

Animals in which the zygote develops into a young one inside the female body, typically leading to higher survival rates.

Pericarp

The protective wall of a fruit that develops from the ovary wall following fertilization.