What is heaven?

According to many religions based on Judaism and Christianity, heaven is a state of existence where a person’s spirit is at last united with God forever. In a number of Christian religions, heaven is believed to be the reward for people who have lived good lives according to certain rules of thought and behavior that God has made known through scriptures (sacred writings, like the Bible) and through the teachings of churches and religious leaders. (Those who have not followed these rules, it is believed by many, go to a place of punishment known as hell.) Many Christians believe that at the end of the world their human forms will be resurrected in a perfect state—just as the body of Jesus Christ was, when he arose from the dead on Easter morning—and join their souls or spirits in heaven for eternity.

This idea has led to the concept that heaven is an actual place—located above—with physical characteristics. Over the centuries, through pictures and writings, people have tried to create images of heaven, imagining a place of perfect happiness perched atop fluffy white clouds. It has often been portrayed as a place full of things that would bring happiness on Earth, possessing, for instance, pearly gates and streets of gold.

What is the origin of Boxing Day?

Beginning in the Middle Ages, Boxing Day was known as St. Stephen’s Day in honour of the first Christian martyr. Although unknown in the United States, Boxing Day is still observed in Britain, Canada, New Zealand, and Australia.

It’s called “Boxing Day” because on the day after Christmas, the well-off boxed up gifts to give to their servants and tradespeople, while the churches opened their charity boxes to the poor.

Why is a lazy, irresponsible person called “shiftless”?

The word shift means to change or rearrange, which is why we call those who work during differing blocks of time “shift workers.” This use of the word shift also applies to an individual’s ability to change or adapt.

Therefore, if you’re “shiftless” you lack the initiative or resources to change with the circumstances. On the other hand, someone who is “shifty” is too adept at change and isn’t to be trusted.

What is the most common household pet in the United States?

According to a national survey conducted by the American Pet Products Manufaturers Association in 2008, Americans owned about 75 million dogs and 88 million cats. Approximately 39 percent of U.S. households own at least one dog, and 34 percent own at least one cat.

According to the American Kennel Club, Labrador retrievers are the most popular dog breed, followed by Yorkshire terriers, German shepherds, and golden retrievers. Persian cats are the most popular feline breed, followed by the Maine coon and the Siamese. Combined reptiles are the next popular type of pet, followed by birds and horses.

How do seeds become plants?

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.

Why do people get wrinkles and gray hair as they get older?

As people age, their bodies change in many ways that affect the ways their cells and organ systems function. These changes occur little by little, progress over time, and are different for every man and woman. We all lose height as we age, and by the time we reach 80 years old, our height may have decreased by two inches (five centimeters). Changes in posture, in the growth of our spine’s vertebrae, and joint changes all contribute to our loss of height. With aging, the hair follicles produce less melanin, the pigment that gives hair its color.

Hair becomes lighter, gray, and eventually turns white. The nails also change with aging: they grow slower, may become dull and brittle, and may become yellowed and opaque. With aging, the outer skin layer (epidermis) thins and the number of pigment-containing cells (called melanocytes) decreases, but the remaining melanocytes increase in size. Aging skin thus appears thinner, more pale, and translucent. Changes in the connective tissue reduce the skin’s strength and elasticity, resulting in a wrinkly, leathery skin.

What does the immune system do?

The immune system protects the human body against germs, which are microorganisms that cause sickness and disease. There are four major types of germs— harmful bacteria (pathogens), viruses, fungi, and protozoa. This defense system begins with the skin, which stops germs from getting into your blood or tissues. If germs get into your body, for example through your nose or mouth, white blood cells called phagocytes and lymphocytes attack them. Phagocytes scout out and destroy invaders, and long-living lymphocytes remember the invaders and release chemicals called antibodies to make the body resistant, or immune, to them.

White blood cells live in the bloodstream, lymphatic system, and spleen. The lymphatic system (or lymph system, for short) is a far-reaching network that extends throughout your entire body. A clear liquid called lymph runs throughout the system, washing the body’s cells with nutrients and water and detecting and removing pathogens. Lymph is filtered through the lymph nodes, and then passes into the body’s bloodstream.

Which planets have rings?

Jupiter, Saturn, Uranus, and Neptune have rings—or thin belts of rocks—around them. Jupiter’s ring is thin and dark, and cannot be seen from Earth. Saturn’s rings are bright, wide, and colorful. Uranus has nine dark rings around it, and Neptune’s rings are also dark, but contain a few bright arcs.

At one time all of the planets, Earth included, had rings. These rings were unstable and the material was either lost in space or collected into the satellites of these planets.

What is moss?

Moss is a type of plant that does not have traditional roots, stems, or leaves. Because they have no true roots, mosses use delicate growths called rhizoids to anchor them to soil, rocks, or tree bark. Moss grows along the ground where it is moist, absorbing water and nutrients from the air.

Like their cousins the ferns and liverworts (leafy mosses), mosses reproduce from spores, not seeds, and need to be moist in order to reproduce. They grow in soft cushions or small clumps, and can spread out like a blanket along the ground.

Why do stars twinkle?

On a clear, dark night in your backyard, you can see about 2,000 or so stars in the sky, a small fraction of the 100,000 or so stars that make up our galaxy. They seem to twinkle, or change their brightness. In reality, most of the stars are shining with a steady light. The movement of air (sometimes called turbulence) in the atmosphere of Earth causes the starlight to get slightly bent as it travels from the distant star through the atmosphere down to the ground.

This means that some of the light reaches us directly and some gets bent slightly away. To the human eye, this makes the star seem to twinkle.