Air flow through them tends to be relatively rapid and turbulent. ... As they divide into smaller and smaller tubes they lose the cartilage in their walls and cross sectional area becomes bigger allowing air flow to slow and become more laminar. ... These are thin walled sacs which have a very elaborate capillary network on their surface facilitating gas exchange. The barrier between blood and air at this point is extremely thin comprising only the specialised respiratory cell epithelium, a basement membrane, a small interstitial space, a basement membrane for the capillary, and the endothe...

• Word Count: 3614
• Approx Pages: 14
• Grade Level: Undergraduate

In fact, atmospheric gases are often divided up into the major, constant components and the highly variable components, as shown in Table 1 and Table 2. ... Scientists divided the atmosphere into four layers according to temperature: troposphere, stratosphere, mesosphere, and thermosphere. ... THE OZONE LAYER The stratosphere contains a thin layer of ozone molecules (with three oxygen atoms) which forms a protective layer shielding life on Earth from the Sun's harmful ultraviolet radiation. ... Some gases in the exosphere actually escape into space. Particles of the solar winds are conc...

• Word Count: 3528
• Approx Pages: 14
• Grade Level: High School

Telescopes and spacecraft have led scientists into the mysterious unknown - space. ... This causes the release of bubbles of gas and magnetic fields that explode into space. ... Like Earth hot air that rises at the planet's equator is replaced with cooler air. Trade winds result from the cooler air to circulate the dust. ... Dust storms also can turn the color of clouds into yellow or red. ...

• Word Count: 4020
• Approx Pages: 16
• Has Bibliography
• Grade Level: High School

When we speak or listen, messages are being sent and received by sound vibrations traveling through the air (ldblquote Music and Computers, 1.1 What is Sound? ... par Humans principally detect the sound waves that travel through air, which are in turn collected by the ear quote s auricle. ... Amplitude can b e defined as the amount of motion that the air molecules of the sound wave undergo. ... The amplitude of a sound wave can be determined by measuring the actual length that the air molecules have displaced and the change in pressure as the wave passes. ... Possible results ...

• Word Count: 3743
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• Grade Level: High School

El Niño has unleashed hurricanes and droughts; the greenhouse effect is blamed for rising temperatures; and the thinning of the ozone layer might lead to an increase in skin cancer among humans" ("Today's Science: Global Warming and Ozone Hole Linked "). ... Vegetation also emits carbon dioxide into the air but only accounts for about fifteen-percent" ("What Human Activities Contribute to Climate Change?"). ... Inlets, where the river meets the sea, will widen out, and cause the sea water to flow into rivers and streams. ... The primary cause is the emission of carbon dioxide int...

• Word Count: 3357
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• Grade Level: High School

• Trees turn carbon dioxide into oxygen that helps us breathe and reduces air pollution. • Trees also filter lots of other chemicals from our air and purify it making the air healthier for us to breathe. ... • They also clean the air by stopping a lot of flying dust particles etc from flying. ... Trees are the essential link in the food chain of life; they capture sunlight and convert it into energy. ... As plants turn sunlight into sugars, through the process of photosynthesis, they use up water. ...

• Word Count: 2774
• Approx Pages: 11
• Grade Level: High School

The air from the fan blew at twenty-five to thirty-five miles per hour and passed through a metal grid which straightened it. ... The largest machine...the longest time in the air, the smallest angle of descent, and the highest wind!" ... Taylor into service. ... It was made of three layers of thin spruce (1 1/8 inch) glued together and shaped with a hatchet and a drawshave. ... This flight lasted only 12 seconds, but it was nevertheless the first in the history of the world in which a machine carrying a man had raised itself by its own power into the air in full flight, had sailed forward...

• Word Count: 2840
• Approx Pages: 11
• Grade Level: High School

Oxygen (gas) - one-fifth of air - used to release energy from nutrients d. ... Sagittal or Median " divides body into left and right portions b. Mid-sagittal " divides body into equal left and right portions c. ... Coronal or Frontal " divides body into anterior and posterior portions 10. ... A thin, delicate layer of connective tissue underlying the epithelium of many organs 5. ...

• Word Count: 2878
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• Grade Level: High School

He stretched his thin arms high above him, and smiled as he felt his muscles tense. ... Lysander grabbed the ends of his air, "Now you're rhyming, too! ... He reached into his pocket for some coins, spinning them across the air to the boys. ... Maybe he ought to save his money for a fancy suit, so he could go into town and get a real job. ... The old man seized them and crawled into his shack. ...

• Word Count: 3593
• Approx Pages: 14
• Grade Level: High School

The Japanese stayed protected from air and naval bombardment in caves and bombarded the Allied forces with no cover on the beaches with unforgiving artillery fire. ... The Japanese had the idea that they were to win this battle so much focus went into this campaign. ... The Japanese forces were stretched thin between the eastern Chinese front, the western U.S. and British front, and the possibility of the third front against the Russians coming back from the victory over the weakening Germans. ... The United States was to fight on land, sea, and air, while the British Commonwealth fought only...

• Word Count: 2698
• Approx Pages: 11
• Grade Level: High School

Introduction In this report I am going to discuss the adaptations of 3 plants groups: xerophytes, hydrophytes and mesophytes relating to plant water balance and I will discuss how these adaptations allow the plant to survive in it's ecological niche. An ecological niche can be defined as the way of ...

• Word Count: 2711
• Approx Pages: 11
• Has Bibliography
• Grade Level: Undergraduate

The hands and arms of early robots were pneumatically powered (air pressure) or hydraulically powered (fluid pressure). ... An operator enters the work movements into a computer which tells the robot what to do. ... Then a thin tungsten wire at the tip of and electrode is brought close to the surface. ... There is a hazard of fire since finishes are flammable, and noise from air discharge can damage hearing. ... Spray finishing robots cut costs because they require less light, reduce fresh-air requirements, reduce exhaust, and lesson energy costs. ...

• Word Count: 2637
• Approx Pages: 11
• Grade Level: High School

Some actually think that these cursed elements of air help rather than hinder the earth! ... The most debated of the gasses, Fluorocarbons (CFCs), now come into view. ... They claim instead that the ozone only thins from its peak from time to time(Howard). ... Don't fall into the greatest scam of this country. ... CFCs come from commonly used items such as aerosol cans, refrigerators, and air conditioners. ...

• Word Count: 4635
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• Grade Level: High School

Not just things we consider "alive", but hills, waterfalls, the air you breathe, all of these had energy. ... He would then take some of his anima and infuse it into what he created. ... For instance, the Standard of Ur uses semi precious stones and shell cut into relief to depict two different scenes. ... The Bull Headed lyre depicts this trend by showing a bulls head, a typical diety of fertility carved into a lyre. ... Each was massive, requiring many men to literally drag it into place. ...

• Word Count: 2959
• Approx Pages: 12
• Grade Level: High School

This trait gives humans an advantage over all other creatures because while the ape may chose to use the stick or bone as a weapon to hunt the man is the only one who would choose to form it into a blade and make a true weapon out of it. ... And that God then blew the breath of life into his nostrils. ... Still with all that the majority of the world believes that man was created out of thin air by an almighty being. ...

• Word Count: 2965
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• Grade Level: High School

His broad shoulders, strong biceps and narrow waist complemented his polo shirt with a custom tailored look and an air of strength that came from working, not working out. ... He was wearing a pair of navy blue slacks and docksides (without socks) but did not have the "I own a boat" or "I play golf" air about him. ... In addition, to his clean cut appearance, he carried himself with an air of confidence – square shoulders, straight spine, calm demeanor. ... She too had a very shiny, thin, gold band on her ring finger but no diamond. ... After she got the baby carrier ...

• Word Count: 3012
• Approx Pages: 12
• Has Bibliography
• Grade Level: High School

Immediately my brothers and sisters ran into the rain. ... It was as if we had stepped into a new and strange place. ... See sulphur dioxide gas in the air dissolves with rain to form acid rain. ... Now when acid rain falls into lakes it changes the acidity in the water. ... Finally, in 1983, the lake reached a pH of 5 and the surviving fish in the lake were thin and deformed and unable to reproduce. ...

• Word Count: 2708
• Approx Pages: 11
• Grade Level: High School

Mortise-and-tenon: a groove cut into stone or wood, called a mortise, that is shaped to receive a tenon, or projection, of the same dimensions. ... Anubis (jackal-headed god) leads Hu-Nefer into a hall where his soul is being weighed against a feather. ...

• Word Count: 10708
• Approx Pages: 43
• Grade Level: High School

She ran without hesitation into the next room and found the baby in the bed. ... The crying women got out of the house and into the fresh air. ... Sawyer rushed into things and if he had taken the time to refine his product he might have been credited with the invention of the first practical light bulb. ... William helped open up the idea of a carbonized filament, a carbonized material drawn into thin wire, to Edison which Edison had not tried. ... The vacuum pump was used to pump the air out of the tube. ...

• Word Count: 4055
• Approx Pages: 16
• Has Bibliography
• Grade Level: High School

I remember seeing on television the very vessels which I had guessed in games of trivia slam into the World Trade Center in New York City. ... Of course, this reluctance faded with the passage of time as I grew older, but the general American attitude toward traveling by air was still distorted. ... I was 30,000 feet in the air and that was good enough for me. ... Before I knew it, the airport which I've grown so close to started to become smaller and smaller as we leaped into the sky. ... Thoughts like "What if a bird flies into the engine?...

• Word Count: 3686
• Approx Pages: 15
• Has Bibliography
• Grade Level: High School

There is a slight breeze, the air is brisk, the sun is high in the sky and feels wonderful. ... The air from the surface is funneling through the tunnel, I pray that the air contact doesn't damage anything important. ... My team of five have decided to break up the area into sections for each to work in. ... I divided the containments of the urn into five separate Strata-Levels. ... The most interesting is a nearly decayed hollow, thin cylinder, enclosed at both sides with the exception of one side having a hole. ...

• Word Count: 2637
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• Grade Level: High School

They then developed a new legless mode of locomotion and diversified into many ecological niches. ... They fit into ten families. ... The effect is that the body is thrown into horizontal waves. ... Each time the victim exhales the snake tightens preventing the animal from inhaling more air. Without air the prey slowly becomes unconscious and dies. ...

• Word Count: 2917
• Approx Pages: 12
• Grade Level: High School

This principle is employed in high-speed trains that travel at 483 km/h (300 mph) while levitating on a cushion of air. ... By combining materials into superconducting alloys, the temperature was raised slightly. ... Using a superconductor's ability to "expel" a magnetic field (or flux) as a criteria, superconductors can be divided into 2 groups. ... Tunnelling occurs when a thin oxide barrier is squeezed between two superconductors. ... In order for a superconductor to be practical for commercial applications, it must be sturdy, reliable, and relatively easy to manufacture and form in...

• Word Count: 2790
• Approx Pages: 11
• Grade Level: Undergraduate

When electron clouds overlap, electrons can move into electron cloud of adjoining atoms. ... Copper is chosen because it can be drawn into long thin wires very easily (it is ductile) and because it is a good conductor of electricity. ... Metals are lustrous or have a silvery surface but this may be easily tarnished by corrosive oxidation in air and water. ... Aluminium is very strong and can be beaten into very thin sheets. ...

• Word Count: 2699
• Approx Pages: 11
• Grade Level: High School

She inhaled sharply at the short compliment, the innocent and soft smell of the wildflowers mixed with the chilled air meeting with her nose, and exhaled with a small giggle. ... She blinked as a slight voice came from what seemed like thin air whispering an inaudible phrase. ... His smile that didn't seem to fit his face transformed into a smirk. ... " Elisabeth burst into tears. Flashbacks began to pour into her memory, and she sobbed loudly. ...

• Word Count: 2531
• Approx Pages: 10
• Grade Level: High School