Célula

Célula
Célula: La célula es un sistema muy complejo que es el centro de intercambios intensos en energía y que presenta áreas extensas de la interfase. Como todos seres vivos, la célula se nutre, crece, se multiplica y muere.
Cromatina : Parte visible al microscópico del núcleo de una célula, que constituye una condensación densa y forma el núcleo.
Núcleo: Parte central de una célula que contiene los cromosomas.
Mitocondria : Organó del citoplasma de las células que se ocupa de la oxidación y el almacenamiento de la energia.
Nucléolo : Particule nuclear que juega un rol en la fisiológica de una célula.
Membrana nuclear : Tejido organico muy delgado que envuelve el nucleo de la célula.
Proteina: Conjunto que contiene aminoacidos, de masa molecular importante.
Grano de melanina : Pigmento de coloracion cutanea.
Membrana plasmatica : Membrana muy delgada que recubre la célula.
Ribosoma : Organito citoplasmico de la célula, se ocupa un rol importante por la sintesis de las proteinas.
Glucogeno: Sustancia que forma glucosa del organismo humano.
Citoplasma: Parte que contiene la célula.
Retículo endoplásmico : Conjunto de fibras de la parte central del citoplasma.
Aparato de Golgi: Sistema de granulacion del citoplasma.
Centriolos: Estructuras cilindricas del centrosoma.
Lisosoma: Organito intracelular que puede absorber las particulas solidas del medio ambiente.

Foto :

EN : Goat
FR : Chèvre
ES : Cabra

Cabra

Domestic goats are one of the oldest domesticated species. For thousands of years, goats have been used for their milk, meat, hair, and skins all over the world. Most goats naturally have two horns, of various shapes and sizes depending on the breed. While horns are a predominantly male feature, some breeds of goats have horned females. Polled (hornless goats) are not uncommon and there have been incidents of polycerate goats (having as many as eight horns), although this is a genetic rarity thought to be inherited. Their horns are made of living bone surrounded by keratin and other proteins and are used for defense, dominance, and territoriality.

Goats are ruminants. They have a four-chambered stomach consisting of the rumen, the reticulum, the omasum, and the abomasum. Goats have horizontal slit-shaped pupils, an adaptation which increases peripheral depth perception. Because goats' irises are usually pale, the pupils are much more visible than in animals with horizontal pupils but very dark irises, such as sheep, cattle and most horses.

Both male and female goats have beards, and many types of goats may have wattles, one dangling from each side of the neck. Some breeds of sheep and goats appear superficially similar, but goat tails are short and point up, whereas sheep tails hang down and are usually longer, though some are short, and some long ones are docked.

Animation : Célula



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Objet virtuel : Célula



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