Реферат

Реферат на тему Frogs Essay Research Paper Frogs Frog is

Работа добавлена на сайт bukvasha.net: 2015-06-21

Поможем написать учебную работу

Если у вас возникли сложности с курсовой, контрольной, дипломной, рефератом, отчетом по практике, научно-исследовательской и любой другой работой - мы готовы помочь.

Предоплата всего

от 25%

Подписываем

договор

Выберите тип работы:

Скидка 25% при заказе до 22.11.2024


Frogs Essay, Research Paper

Frogs

Frog is the common name for a species of

amphibian that also includes toads. A very common

question is whats the difference between frogs and

toads? , the answer: none, except for the fact that toads

lack the powerful legs that frogs have. Where can frogs

and toads be found? , one might ask. They live in all

parts of the world, except for Antarctica, but are mostly

found in tropical areas. Frogs are small animals with

smooth moist skin, and big eyes that can see in almost

any direction. Most species have webbed feet and

powerful legs making them good jumpers, and excellent

swimmers. A frogs tongue is attached to the front of it s

mouth instead of the rear, and most frogs are very vocal,

especially the male frogs.

As a frog grow, it goes through many changes.

Starting out as a tadpole, and morphing into a frog.

Most frogs lay their eggs in water. Others will lay their

eggs some where safe, then carry them to water where

they hatch into tadpoles. At this stage they have gills,

no legs, and a tail. As they mature, their gills and tail

disappear, and they develop lungs and legs. This period

of tadpole life can be divided into three stages. The first

stage, called premetamorphosis, lasts about 50 days

(Patent 54). The second stage, in which the hind legs

grow, is called prometamorphosis, and lasts about 21

days. When the legs are about as long as the body, the

third stage, which is called metamorphic climax, and

takes place very rapidly, begins. During this last stage,

which lasts about a week, many great changes occur.

They lungs complete their development, and the gills

disappear. The skin gets thicker, nostrils form, and the

tail is completely resorbed.

Most frogs prefer moist regions, and many kinds

live in the water. Because frogs absorb oxygen in water

through their skin, they can stay underwater for long

periods of time. A frogs body temperature depends on

it s surroundings, and during cold weather, frogs dig

burrows in mud and hibernate. During hibernation, the

frog needs little oxygen and no more food than is already

in it s tissues. During intense heat, a frog might

estivate, or in other words, lie in a state of torpor during

the heat, after burying themselves in sand and clay.

Frogs are carnivores. They eat just about anything

smaller than then that moves. A frog thinks like this: If

it s smaller than itself and moves, eat it. If it s the same

size, mate, or attempt to mate (this gets some frogs in

lots of trouble). If it s bigger than itself, run. Their diet

may include insects, worms, spiders, or even centipedes.

Aquatic frogs sometimes eat other frogs, tadpoles, and

small fish. Large frogs can eat can eat stuff as big as

mice and snakes. Sometimes a frog eats something too

big to swallow all at once, and will leave it sticking out

of its mouth ingesting it gradually or even choking and

regurgitating it. So virtually, the size of a frog s dinner

is determined by the size of it s mouth. If a frog eats

something poisonous or bad for them, they can throw up

their entire stomach and wipe it with their right front leg.

Frogs help out humans in many ways. Toads are

used world wide as pest control in gardens and on farms.

One toad alone can consume thousands of insects.

Frogs have been used as food for centuries. Efforts have

been made to harvest frogs, but most frogs eaten today

are taken from their natural habitat. People in South

America, the South Pacific, Philippine Islands, and parts

of Africa savor frogs, and consider them a delicacy. The

Chinese and French are lovers of frogs legs. One of the

reasons frogs legs are so expensive is the great demand

for frogs in scientific and medical laboratories. Because

their skeletal, muscular, digestive, nervous, and other

systems are similar to those of higher animals, frogs are

very important in these in these fields of research.

One large and nearly worldwide family of frogs are

the true frogs, many species combined that are well

known (Encarta True Frogs). The Bullfrog is one of the

largest true frogs in North America (Barker 150). It

weighs up to 1.2 pounds and has a total length of 15

inches. One of the most common North American

species is the leopard frog (Barker 154), which is easily

recognized by the numerous black, often light-edged

spots on the back and legs. Most true frogs stay close to

ponds and streams, but the North American wood frog

(Stebbins 135), a small redish-brown species with

mask-like black bands on the head, wander far away

from the water. The green frog is another common

species in North America and despite their name, some

green frogs are brown. Two well-known true frogs of

Europe are the common European frog, which resembles

the wood frog, and the edible frog, a popular food in

Europe. The African Giant Frog, the largest of all frogs,

which grows as long as 26 inches and weighs as much as

10 pounds, is also a true frog . The smallest frog is

probably the Psyllophyne Didactyla from Brazil which is

about 9.8 mm as an adult.

The frogs and other amphibians of North America,

and those of other continents too, are important in the

way all wild things are important. They are also a living

resource that needs protection and greater understanding

to appreciate its true worth.

Today there is a strong effort by all forms of

government to set aside areas that furnish the sort of

environments required by many forms of wildlife,

including frogs. Private organizations and individuals

too have established many special areas mostly free from

conditions that disturb natural habitats. People are

finally realizing that, hey, frogs aren t such bad guys and

maybe we should keep them around.

312


1. Реферат Государство 2 Понятие государства.
2. Реферат Механизм воздействия на организм некоторых химических веществ широко используемых в промышленнос
3. Лабораторная работа на тему Ряд распределения функция распределения
4. Реферат на тему Alicia My Story Book Summary Essay Research
5. Реферат Теории происхождения славян
6. Реферат на тему Racing Feeling Life In The Fa Essay
7. Реферат Преобразование Фурье
8. Реферат Псевдосинонимия критическая ситуация в познании 2-го рода
9. Реферат на тему Emma Jane Austen Essay Research Paper Essay
10. Сочинение на тему Тургенев и. с. - Образ базарова в романе тургенева отцы и дети.