Fleas are perfectly designed by
nature to feast on anything containing blood. Like a shark in the water or a
wolf in the woods, fleas are ideally equipped to do what they do, making them
very difficult to defeat. The bodies of these tiny parasites are extremely
hardy and well-suited for their job.
A flea has a very hard exoskeleton,
which means the body is covered by a tough, tile-like plate called a sclerite.
Because of these plates, fleas are almost impossible to squish. The
exoskeletons of fleas are also waterproof of fleas are also waterproof and shock
resistant, and therefore fleas are highly resistant to the sprays and chemicals
used to kill them.
Little spines are attached to his
plate. The spine the flea scurries through an animal’s fur in – search of
grooming pet tries to pull a flea off through the hair coat, these spines will
extend and stick to the fur like Velcro.
Fleas are some of the best jumpers
in the natural world. A flea can jump seven inches, or 150 times its own
length, either vertically or horizontally. An equivalent jump for a person
would be 555 feet, the height of the Washington Monument. Fleas can jump 30,000
times in a row without stopping, and they are able to accelerate through the
air at an incredibly high rate – a rate which is over ten times what humans can
withstand in an airplane.
Fleas have very long rear legs with
huge thigh muscles and multiple joints. When they get ready to jump. They fold their
long legs up and crouch like a runner on a staring block. Several of their
joints contain a protein called resilin, which helps catapult fleas into the
air as they jump, similar to the way a rubber band provides momentum to a
slingshot. Outward facing claws on the bottom of their legs grip anything they
touch when they land.
The adult female flea mates after
her first blood meal and begins producing eggs in just 1 to 2 days. One flea
can lay up to 50 eggs in one day and over 2,000 in her lifetime. Flea eggs can
be seen with the naked eye, but they are about the size of a grain of salt. Shortly
after being laid, the eggs begin to transform into cocoons. In the cocoon
state, fleas are fully developed adults, and will hatch immediately if
conditions are favorable. Fleas can detect warmth, movement, and carbon dioxide
in exhaled breath, and these three factors stimulate them to emerge as new
adults. If the flea does not detect appropriate conditions, it can remain
dormant in the cocoon state for extended periods. Under ideal conditions, the
entire life cycle may only take 3 weeks, so in no time at all, pets and homes
can become infested.
Because of these characteristics,
fleas are intimidating opponents. The best way to control fleas, therefore, is
to take steps to prevent an infestation from ever occurring.
The primary purpose of the passage
is to
The purpose of education is to make the student an expert in his
subject. This must be clearly understood, and mere mudding through lessons and
lectures and books and passing examinations are relegated to secondary
importance as means to the end-which is excellence in the field chosen.
But there are so many fields, and no man can become an expert in all the
fields it is necessary to decide which fields are important ones that a man
should know well.
It is clear that one’s own work is the most important. This has been realized
and modern civilization has accordingly provided vocational education. It is
now possible to acquire high professional skill in the various fields,
medicine, engineering production, commerce and so on-but with good and bad
mixed together, and no standard for guidance.
The purpose of education is to make the student:
The Baxter house is located at the
end of the street. This house sits farther back from the curb than the other
houses. It is almost difficult to see from the road without peering behind the
deformed oak tree that has obscured it for years. Even so, the Baxter house
stands out from the other houses on the street. It is tall and white. However,
this white is no longer pristinely white, but a dingy grayish cram color. Long
vines hang from the tattered roof. The Baxter house is two stories tall and has
a large yard in the back that has never been mowed. The other houses on the
street are a mere one story and have been painted a variety of colors. The
newer, single story properties all appear to have been built around the same time;
the yards mostly being of the same size, and the houses appearing to be clones
of one another. Aside from the Baxter house at the end, this street is a
perfect slice of middle America. The inhabitants of the other houses wonder who
lives in the ancient, dilapidated house at the end of the street.
The inhabitants of the other
houses
Yellowstone National Park is the
U.S. States of Wyoming, Idaho and Montana. It became the first National Park in
1872. There are geysers and hot springs at Yellowstone. There are also many
animals at Yellowstone. There are elk, bison, sheep, grizzly, black bears,
moose, coyotes, and more.
More than 3 million people visit
Yellowstone National Park year. During the winter, visitors can ski or go
snowmobiling there. There are also snow coaches that give tours. Visitors can
see steam (vapor water) come from the geysers. During
other seasons, visitors can go boating or fishing. People can ride horses
there. There are nature trails and tours. Most visitors want to see Old
Faithful, a very predictable geyser at
Yellowstone Visitors can check a schedule to see the exact time that Old
Faithful is going to erupt. There are many other geysers and boiling springs in
the area. Great Fountain Geyser erupts every 11 hours. Excelsior Geyser
produces 4,000 gallons of boiling water each minute! Boiling water is 100
degrees Celsius, or 212 degrees Fahrenheit – that’s very hot! People also like
to see the Grand Prismatic Spring. It is the largest hot spring in the park. It
has many beautiful colors. The beautiful colors are caused by bacteria in the water. These are forms of life that
have only one cell. Different bacteria live in different water temperatures. Visiting Yellowstone National Park can be a week
– long vacation or more. It is beautiful and there are activities for everyone.
Boiling water is
Arrowheads, which are ancient
hunting tools, are often themselves ‘hunted’ for their interesting value both
as artifacts and as art. Some of the oldest arrowheads in the United States
date back 12,000 years. They are not very difficult to find. You need only to
walk with downcast eyes in a field that has been recently tilled for the spring
planting season, and you might find one.
Arrowheads are tiny stones or pieces
of wood, bone, or metal which have been sharpened in order to create a tipped
weapon used in hunting. The material is honed to an edge, usually in a
triangular fashion, and is brought to a deadly tip. On the edge opposite the
tip is a flared tail. Though designs vary depending on the region, purpose, and
era of the arrowhead’s origin, the tails serve the same purpose. The tail of
the arrowhead is meant to be strapped onto a shaft, which is a straight wooden
piece such as a spear or an arrow. When combined, the arrowhead point and the
shaft become a lethal projectile weapon to be thrown by arm or shot with a bow
at prey.
Indian arrowheads are important
artifacts that give archeologists (scientists who study past human societies)
clues about the lives of Native Americans. By analyzing an arrowhead’s shape,
they can determine the advancement of tool technologies among certain Native
American groups. By determining the origin of the arrowhead material (bone,
rock, wood, or metal), they can trace the patterns of travel and trade of the
hunters. By examine the location of the arrowheads, archeologists can map out
hunting grounds and other social patterns.
Arrowheads are commonly found
along riverbanks or near creek beds because animals drawn to natural water sources
to sustain life were regularly found drinking along the banks. For this reason,
riverbeds were a prime hunting ground for the Native Americans. Now, dry and
active riverbeds are prime hunting grounds for arrowhead collectors.
Indian arrowheads are tiny pieces
of history that fit in the palm of your hand. They are diary entries in the
life of a hunter. They are museum pieces that hide in the dirt. They are
symbolic of the eternal struggle between life and death.
In the final
paragraph, the author writes, “They are museum pieces symbolic of the eternal
struggle between life and death.” Which of the following is the best way to
combine these two sentences, while keeping their original meaning?
Educational planning should aim at meeting the educational needs
of the entire population of all age group. While the traditional structure of
education as a three layer hierarchy from the primary stage to the university
represents the core, we should not overlook the periphery which is equally
important. Under modern conditions, workers need to rewind, or renew their
enthusiasm, or strike out in a new direction, or improve their skills as much
as any university professor. The retired and the age have their needs as well.
Educational planning, in their words, should take care of the needs of
everyone.
Our structures of education have been built up on the
assumption that there is a terminal point to education. This basic defect has
become all the more harmful today. A UNESCO report entitled ‘learning to Be’
prepared by Edgar Faure and others in 1973 asserts that the education of
children must prepare the future adult for various forms of self – learning. A
viable education system of the future should consist of modules with different
kinds of functions serving a diversity of constituents. And performance, not
the period of study, should be the basis for credentials. The writing is
already on the wall.
In view of the fact that the significance of a commitment of
lifelong learning and lifetime education is being discussed only in recent years
even in educationally advanced countries, the possibility of the idea becoming
an integral part of educational thinking seems to be a far cry. For, to move in
that direction means such more than some simple rearrangement of the present
organization of education. But a good beginning can be made by developing Open
University programs for older learners of different categories and introducing
extension services in the conventional colleges and schools. Also these
institutions should learn to cooperate with the numerous community
organizations such as libraries. Museums, municipal recreational programs,
health services etc.
What is the main thrust of the author?