Laboratório de Tecnologia Educacional BIBLIOTECA DIGITAL               DE CIÊNCIAS

60 a 70 cm. The top of the head, the back and the wings are black and the other parts of the body are mostly grey. The immature is brown and striated. Distribution: All over the world, except from the poles and Australia. Habitat: Slow flowing rivers, lakes, reservoirs and swamps. Diet: Aquatic insects, mollusks, crustaceans, fish, amphibians and reptiles. May also eat carrion and rests of food fallen from other bird’s nests, including dead hatchlings. Reproduction: Breeds in colonies together with other species of herons. The nests are built from 1 to 7m from the ground or water. Lays two or three bluish green or buffy eggs. Natural history: During most of the day it rests...

Physical appearance: 17,5 cm. The male is bluish black with the forehead and chest chestnut. The female is olive brown streaked in brown in the upper parts. The immature is brown and striated. Distribution: Eastern South America from French Guyana to northern Argentina and as far west as Mato Grosso and eastern Bolivia. Habitat: Lives in humid grasslands, wetlands and ponds. Diet: Feeds mainly on insects and seeds, but also on fruits. Reproduction: Often nests in groups. The nest is built in a fork of a tree. Both male and female build the nest watering the material before using it. The nest is a deep basket. Natural history: The vocalization is melodic and commonly the predomi...

Physical appearance: 26 cm. The upper parts are green, somewhat yellow, barred in black. The inferior parts are buffy or white, also barred. The tail and the top of the head are black. The male has a red spot below the eye while in the female this spot is black. Distribution: From Eastern Amazon to Uruguay and Argentina. Habitat: Forest borders, gallery and secondary forests, woods and parks in cities. Diet: Feeds on ants and insect larva, mainly beetles. Also eats fruits. Reproduction: After courtship the couple builds a nest inside an old tree, sometimes palm trees and others. The nest is generally downwards, avoiding the water when it rains. Two to four eggs are laid and the ...

48 cm. The face is grey, the chest cinnamon and the belly black. There is a large white spot in the wings, more evident when flying. The beak and feet are red. Males and females are similar. The immature is grayish brown Distribution: From Texas (U.S.A) to Bolivia and Argentina. Habitat: Lives in lakes, rivers, wetlands and even in mangroves. Diet: Feeds on leaves, small seeds and aquatic invertebrates. Reproduction: The nest is built on the ground or hollow trees. The eggs are white, sometimes greenish or bluish. More than one female may lay eggs in the same nest and sometimes may even lay eggs in other species’s nests such as the white faced whistling duck (Dendrocygna viduata)....

75 cm. Aquatic with narrow beak curved in the tip. The feet are webbed. The body is black and sometimes the throat is yellow. In the breeding season the male has some white feathers in the throat and ear region. The immature is fuliginous. Distribution: From Mexico to Southern South America Habitat: Lives in lakes, swamps and estuaries. Diet: Feeds on fish, even spiny ones. The gastric acids dissolve the spines. Reproduction: The nest is built on tall trees near lakes, sometimes mixing with heron flocks. Natural history: It is an excellent diver. When in flocks may pen fish schools, leading them to shallow water where they catch the fishes in frenzy. When it goes out of the wate...

36 cm. The legs and the beak are yellow. The tail is short and the wings are broad, with a somewhat rectangular shape when flying. The chest is light brown streaked in different colors and the upper parts are in shades of gray. The immature is brown and striated. The female is slightly larger than the male. Distribution: From Mexico to Argentina. Habitat: Inhabits cerrado, gallery and secondary forests, fields, farms and cities. Diet: Big insects, amphibians, small lizards , mammals and birds. Sometimes hunts perched bats. May follow groups of coatis or monkeys, catching animals displaced by their movements. Reproduction: The nest is a platform built on the top of tall trees....

25 cm. The body is brownish grey, with the upper parts darker . The tip of the tail is white. There are two horizontal black bands in the sides of the head and on the wings. The male is bluish on the top of the head. Distribution: South America. Habitat: Open fields, cerrado, caatinga, crops, parks, lawns, urban areas. It is benefitted by deforestation Diet: Mainly grains, but also small fruits. When breeding also consumes snails and millipedes. Reproduction: During courtship the male produces a low sound different from its usual one. The male exhibits its strength to the female and the couple caresses each other in the head. The nest is a platform made of sparse sticks built on t...

91cm. The neck and the legs are thin and long. All white, but with iris, beak and legs yellow. Distribution: Throughout the world. Habitat: Lakes, rivers, ponds, reservoirs, swamps, mangroves, estuaries and even polluted rivers. Diet: Eats fishes, amphibians, insects. The author witnessed an egret catching and eating a mouse in a riverbank in Campinas-SP. Reproduction: Breeding takes place generally in the end of the dry season, when the food supply is more abundant for this species. During this period the adults have the egrets that are long feathers used in the courtship. The breeding couples gather in nesting sites that may have hundreds of individuals, sometimes mixing with o...

A lactato desidrogenase é uma enzima citosólica envolvida na transformação de piruvato a lactato e viceversa. Ela participa da glicólise anaeróbica no músculo esquelético e na hemácia, da gliconeogênse hepática e do metabolismo aeróbico no músculo cardíaco. A determinação da sua atividade auxilia no diagnóstico de várias doenças já que a sua atividade se encontra aumentada no soro de pacientes acometidos por infarto de miocárdio, hepatite aguda, distrofia muscular e neoplasias. Este trabalho apresenta um objeto de aprendizagem, mediado por computador, que contem a simulação da determinação laboratorial da atividade da lactato desidrogenase sérica, pelo método do decréscimo da absorvância em ...

A Resistência Insulínica (RI) refere-se à diminuição da ação da insulina nas células alvo, adipócitos e células musculares. Pode ser uma condição genética ou adquirida. O estudo sobre Resistência Insulínica tem sido complementar as pesquisas que envolvem diabetes, obesidade, hipertensão, além de dislipidemia e cardiopatia isquêmica, pois através deles são fornecidos novos parâmetros e tratamentos para a RI. Há uma ligação particular entre RI e Diabetes Mellitus Tipo 2 (DM2), mesmo sendo tema de muitas controvérsias. O metabolismo de minerais como o zinco e o magnésio se mostram alterados na presença da obesidade, sendo que estes são importantes em mecanismos enzimáticos. A deficiência desse...