Biology

Transitional fossil

Translation (genetics)

Transposable element

Trapezius muscle

Tree of life (biology)

Tree of life (biology): evolutionary relationships and phylogenetic concepts

Trematode

Trematode (fluke): parasitic flatworms and their life cycles

Tremor

Tremor: involuntary rhythmic muscle movement and its causes

Treponema

Treponema: overview of the spirochete genus and related human infections

Triatominae

Triatominae (kissing bugs): biology, distribution, and public health importance

Tribe (biology)

Tribe (biology): a taxonomic rank between subfamily and genus

Triceps brachii muscle

Trichomonas gallinae

Trinomen

Trinomen (zoological trinomial name)

Trinomial nomenclature

Trinomial nomenclature (three-part scientific names)

Trochophore

Trophallaxis

Trophallaxis: social transfer of food and information

True bug

Trunk

Trunk: meanings and uses of 'trunk' in nature, anatomy, transport and technology

Trypanosoma

Trypanosoma: parasitic kinetoplastid protozoa and their medical importance

Trypanosomatida

Trypanosomatida: parasitic kinetoplastid protists

Tryptophan

Tube feet

Tube feet (podia) — locomotion, feeding and respiration in echinoderms

Tube worm

Tubule

Tubule: small tubular structures in biology and anatomy

Turgor

Turgor (cellular turgidity)

Twin

Twin (Biological and Human Context)

Type species

Type species: definition, rules and role in biological nomenclature

Type specimen

Type specimen (biology)

Ulna

Umbilical cord

Unicellular organism

Unicellular organism (single-celled life)

Unikont

Uracil

Uracil: the pyrimidine base of RNA

Urinary system

Urination

Urination (micturition)

Urine

Urine: physiology, composition, and uses

Urinogenital

Urinogenital: the urinary and reproductive systems and their openings

Uterus

Uterus (womb): structure, function, and clinical significance

Vacuole

Vacuole (cell organelle): structure, functions and biological roles

A vacuole is a membrane-bound compartment in eukaryotic cells that stores substances, maintains turgor, aids digestion and recycling, and performs specialized roles in plants, fung

Vagina

Vagina (female reproductive canal)

Vaginal flora

Vaginal lubrication

Vagrancy (biology)

Vagrancy (biology): causes, occurrences, and ecological significance

Variation

Biological variation: causes, types and role in evolution

Vas deferens

Vascular dementia

Vasoactive intestinal peptide

Vasoconstriction

Vasoconstriction: mechanism, roles, and clinical significance