In details

Glossary - Letters U / V / W


Ulcer - Generically, superficial lesion of an organ. Peptic ulcers are ulcers of the stomach mucosa and duodenum.

Unicellulars - Consisting of only one cell.

Univitelines - Same calf. See homozygote.

Urea - Substance produced by vertebrate liver from ammonia and carbon dioxide. Its synthesis is a way to reduce the ammonia toxicity produced in cellular metabolism.

Vacuole - Generic name of a small pouch present in the cytoplasm of cells, whose content is variable (aqueous solutions, foods, enzymes, etc.).

Cytoplasmic Vacuole - Membrane-limited cytoplasm space designation. Vacuoles are named after their origin or function. Eg phagosome (originates from phagocytosis); digestive vacuole (intracellular digestion function).

Contractile Vacuole - Vacuole present in freshwater protozoa (amoeba, paramecium, etc.) responsible for eliminating, at regular pulses, excess water entering the cytoplasm due to osmosis.

Digestive Vacuole - Membranous pouch formed by joining lysosomes with phagosomes or pinossomes, where intracellular digestion occurs.

Pulsatile Vacuole - Same as Contractile Vacuole.

Vascular - Relative to vessels. It has blood vessels (animal) or conductive vessels (vegetables).

Vase - Tubular structure through which materials are conducted.

Phagocytic Vesicles - Same as phagosome (see cytoplasmic vacuole).

Watson - James Watson, an American geneticist and biophysicist who worked with Francis Crick to model the molecular structure of DNA.

Weismann - August Weismann, German biologist who lived between 1834-1914. It was Weismann who first established the difference between somatic and germ cells. This biologist became famous for his experiments (such as cutting off the tail of mice for several generations) to prove that Lamarck's theories were wrong and that the acquired characteristics could not be passed on to offspring.

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