Walking with your dog strengthens the bond between you and your pet, and it is also the healthy thing to do. Dogs, like people, benefit from exercise to help control weight and to maintain a healthy heart, lungs, and muscles. They love going for a walk, running and jumping, and retrieving a ball or Frisbee. Aging pets must be kept as agile and fit as possible, but may not be motivated to exercise without encouragement. The pleasure of your company is one of your dog’s greatest motivations to exercise.
In addition to exercise, dogs also need social interaction, positive attention from their owner, and mental stimulation. Many of these needs can be met by simply taking your dog for a walk. Always remember to walk your dog on a secure leash (with identification tags) and pick up after your pet. During warm weather carry water for your pet, and always pause when your dog needs a rest.
Indeed, it does. A Venus flytrap is a carnivorous plant that attracts, captures, and kills insects and digests and absorbs their nutrients. The leaves of the Venus flytrap, Which can open wide, have short, stiff hairs called trigger hairs. When anything touches these hairs enough to bend them, the two lobes of the leaves snap shut, trapping whatever is inside. The “trap” will shut in less than a second, capturing flies and other insects.
When the trap closes over its prey, finger-like projections called cilia keep larger insects inside. In a few minutes the trap shuts tightly and forms an air-tight seal in order to keep its digestive fluids inside. These fluids help the plant digest prey. At the end of the digestive process, which takes from 5 to 12 days, the trap reabsorbs the digestive fluid and reopens. The leftover parts of the insect blow away in the wind or are washed away by rain.
Schools are different in every country in the world. A school may have lots of classrooms, books, play equipment, and a playground, or lessons may take place under trees or in an open outdoor space. A temple, a tent, or a building on stilts may serve as a classroom for some children. In poor places that have no money to build schools, children may learn their lessons outdoors. In isolated places—such as the Australian outback or the Alaskan wilderness—where families live hundreds of miles apart and far from cities or towns, children may get their lessons from teachers over two-way radios or the Internet. All around the world, schools are a reflection of the culture in which they are formed.
In Japan, as students enter school, they remove their shoes and put on slippers, a Japanese custom. They do not write with pencils; instead, each child has his or her own ink well, brush, and ink for writing the kanji (Japanese characters). Children often clean their classrooms (including dusting cubbies and mopping floors), and at the end of each class the students thank their teacher and bow. In schools in Brazil and other South American countries, children often go to school barefoot. In India, children practice yoga in school. And many children that go to public schools in European countries, such as Germany and France, ride their bikes to school or take public transportation, rather than school buses.
Earrings were used by seamen, especially warriors such as pirates, for very practical reasons and not for decoration. They were given to young sailors as a symbol of their first crossing of the equator, and their purpose was to protect the eardrums during battle.
The pirates, especially those who fired the ships’ cannons during closed combat with the enemy, dangled wads of wax from their earrings to use as earplugs.
Frogs are able to make their croaking noises because they have simple vocal cords that have two slits in the bottom of the mouth. These slits open into what is called a vocal pouch. When air passes from the lungs through the vocal cords, a sound is produced. The inflating and deflating vocal pouch makes the sound louder or quieter.
That sound changes depending on the kind of frog there are as many different kinds of croaks as there are frogs! Frogs croak for the same reasons that many animals make noises: to track down and then select a mate, and to protect their territory from other male frogs.
Just as telephones are connected by a worldwide phone system, home and work computers can connect with a global computer communications network known as the Internet. Each computer that is linked to the system has its own Internet address, as individual as a phone number. Home computer users buy the services of an Internet provider, which is an organization with powerful computers that link all its subscribers to the Internet.
Many large organizations and companies have computers that link them directly to the network. Internet users can visit the World Wide Web, which is a global network of Web sites providing information, entertainment, products, and other services.
People usually read newspapers to get information about current events, things that are happening at the present time or have just occurred. When a good news story breaks, reporters are immediately sent out to gather as much information about the situation as possible and photographers take pictures that add visual information. When they return to the newspaper office, the reporters type their story into a computer, and camera film is developed into photos in a darkroom. The photographs are put into the computer with a device called a scanner. Increasing numbers of photographers use digital cameras, which means their photos do not have to be first developed on paper. They are automatically in digital, or computer-ready, format and can be transmitted over phone lines or via satellites just like e-mail or other electronic files. Once the photos are in digital format, the printed story and the pictures that illustrate it are arranged together. The story may take up part of a newspaper page or may extend for a few pages. Designers arrange all the stories and photos that make up a newspaper into visually appealing, easy-to-read pages on the computer screen. They are then printed out on pieces of clear film. Next, the film print of each newspaper page is laid on a light-sensitive metal plate. When it is exposed to a flash of bright light, shadows of the film’s letters and pictures are left on the plate. The shadows are permanently etched or marked into the plate when it is soaked in acid, which eats some of the metal away. What is left is a perfect copy of the film print of the newspaper page, with its words and pictures appearing as grooves in the metal.
The newspaper page is now ready to be printed on paper. The metal plate is first wrapped around a roller on a motor-driven printing press and coated with ink. After being wiped clean, ink still stays in the grooves. When paper (in big rolls) is passed under the roller, it is pressed into the grooves, and perfectly printed pages appear. This process is repeated for each newspaper page. As you can imagine, printing plants are enormous, with some presses standing three stories tall. These expensive machines (costing tens of millions of dollars) can print and sort up to 70,000 copies of a newspaper per hour. Once the press is done printing and sorting, the newspapers are bundled for delivery the next day to homes and newsstands.
An avalanche is a huge mass of ice and snow that breaks away from the side of a mountain and slides downward at great speed. Most avalanches result from weather conditions, such as heavy winds and earth tremors, that cause snow on a mountain slope to become unstable.
A large avalanche in North America might release 300,000 cubic yards of snow—the equivalent of 20 football fields filled 10 feet (3.3 meters) deep with snow. Wintertime, particularly from December to April, is when most avalanches occur.
Once seeds are fully developed, they need a good place to grow. If they just fell to the ground beneath their parent plant, they would struggle, competing against each other for sunlight, water, and minerals. Most seeds need to travel—by wind, water, or with the help of insects and other animals—to better places to germinate, or start to grow into new plants. Some seeds, like those from conifer and maple trees, have wings attached. Others, like those of dandelions, have parachutes made of tiny hairs. Both features allow the seeds to be carried great distances by the wind, and they sometimes land in spots that are good for germination. Water carries other seeds to good growing places; the hard, watertight shell of a coconut, for instance, allows it to travel many miles at sea before finding a beach where conditions are suitable for growth.
Seeds sometimes have to wait a long time before they find good places to grow, places where the sun, moisture, and temperature are right. Most seeds are designed for the wait, protected by a hard outer pod (except those of conifers). Some seeds wait years to germinate, and some just never do. But inside each seed pod is a baby plant, or embryo, and endosperm, a supply of starchy food that will be used for early growth if germination takes place. Then a tiny root will reach down into the soil, and a tiny green shoot will reach up, toward the light.
Often parents and guardians work with their kids to create an online agreement that outlines the rights and obligations of computer use at home. It might be a list of rules that you agree to together, or it might be a more formal contract that both the parent and the child sign. It covers topics like where kids can go online and what they can do there; how much time they can spend on the Internet (and how much of that time is dedicated to school work); and what they should do if anything or anyone makes them feel uncomfortable. You can write down the rules for protecting your personal information and how to use chat rooms, newsgroups, and instant messaging services. Families often print the rules out and keep them by the family computer to remind everyone of the rules.