Class 11 Biology Vocabulary Flashcards

Vocabulary flashcards generated from the Class 11 Biology lecture notes covering fundamental biological concepts, anatomical structures, and physiological processes.

Binomial Nomenclature

A standardized system of naming living organisms where each scientific name consists of two parts: the genus name and the specific epithet.

Taxon

A scientific term used to denote a specific unit or category at any level of biological classification.

Taxonomic Hierarchy

The systematic framework arranging various taxonomic categories in an ascending order from species up to kingdom.

Systematics

The branch of biology concerned with the study of diverse organisms, their identification, classification, and evolutionary relationships.

Herbarium

A storehouse of collected plant specimens that are dried, pressed, and preserved on mounting sheets for botanical reference.

Metabolism

The sum total of all chemical reactions occurring continuously within a living organism to maintain life.

Mycoplasma

A genus of bacteria that completely lack a cell wall and represent the smallest known living cells capable of surviving without oxygen.

Diatomaceous Earth

A soil deposit composed of the indestructible silica cell walls left behind by diatoms over millions of years.

Heterocyst

A specialized, thick-walled cell found in filamentous cyanobacteria (such as Nostoc and Anabaena) that performs nitrogen fixation.

Plasmogamy

The fusion of protoplasms between two motile or non-motile gametes during fungal sexual reproduction.

Karyogamy

The fusion of two haploid nuclei resulting in a single diploid nucleus.

Dikaryon

A fungal cell stage containing two distinct, un-fused haploid nuclei ($n + n$) per cell.

Apoplast

The non-living system of cell walls and intercellular spaces through which water and solutes move freely across plant tissue.

Symplast

The continuous network of living protoplasts interconnected by plasmodesmata in plant tissues.

Guttation

The loss of liquid water droplets from hydathodes or uninjured leaf margins caused by positive root pressure.

Transpiration

The evaporative loss of water vapor from the aerial surfaces of a plant, mainly through the stomata.

Zwitterion

An amino acid molecule possessing both positive ($-\text{NH}_3^+$) and negative ($-\text{COO}^-$) electrical charges simultaneously.

Prosthetic Group

An organic cofactor tightly or permanently bound to the apoenzyme necessary for enzymatic activity.

Co-enzyme

A non-protein organic molecule that transiently binds to an enzyme to assist in catalyzing reactions.

Cell Cycle

The sequence of events where a cell duplicates its genome, synthesizes cellular components, and splits into daughter cells.

Chiasmata

The X-shaped crossing sites formed between non-sister chromatids of homologous chromosomes during diplotene of meiosis I.

Photoperiodism

The developmental response of a plant, such as flowering, to the relative duration of light and dark periods.

Vernalisation

The process where flowering in plants is promoted or induced by a period of cold temperature exposure.

Emphysema

A chronic pulmonary disease involving the breakdown of alveolar walls, which significantly reduces the surface area available for gas exchange.

Juxtaglomerular Apparatus (JGA)

A specialized cellular structure formed by DCT cells and afferent arterioles that regulates renal blood pressure and glomerular filtration rate.

Sarcomere

The functional contractile unit of myofibril bounded between two consecutive Z-lines in skeletal muscle tissue.

Synapse

The functional junction between two neurons or between a neuron and a target cell through which nerve signals pass.