G.1 Choose the topic sentence that best captures the main ide

Hawaiian surfers George Freeth and Duke Kahanamoku helped establish the sport in California, Australia, and New Zealand. Surfing, popular in pre-colonial Hawaii, was used to attract tourists visiting Waikiki Beach in the early twentieth century. The first surfboards were made of solid wood, but in the 1930s, American Tom Blake developed a cheaper, lighter version that attracted new surfers.

A number of factors influenced the spread of surfing's popularity in the early twentieth century

If adult tundra swans are threatened by predators—especially humans, bears, or wolves—they may leave their nests to draw attention away from their young. Tundra swans breed on the Arctic tundra in North America and must protect their chicks from the cold by building nests made of grasses and moss. Tundra swan parents lead their young to feeding sites in the water, where the adults bring up submerged food.

Adult tundra swans use several strategies to protect and nurture their young in the Arctic.

Lions feed on large herbivores like zebras and giraffes. Elephants graze on grasses and break down plants, making the vegetation edible for smaller herbivores. Vultures eat meat left over by large predators.

Animals in the African savanna depend on other animals in their ecosystem to survive

Camp with a friend and become familiar with the locations of nearby telephones and ranger stations. Leave an itinerary for your trip, including your return date, with a trustworthy person. Research the weather conditions forecasted for your camping destination.

As you plan a camping trip, you can take a few simple measures to help prepare for emergencies

Cell phones can be used to cheat on tests by sending answers to friends or by accessing the Internet. Texting during class is like passing notes and is a waste of time. If cell phones aren't properly silenced, they can interrupt classroom activities.

Cell phones in the classroom can have a negative impact on student learning

Male chameleons display bright colors to signal that they are ready to mate. While chameleons are usually brown or green, they may turn darker or lighter to warm up or cool off. Chameleons may change colors to express emotional states, such as fear, anger, and surprise.

Chameleons change color as a response to varying emotional and physical states

Charles Schulz's "Little Red-Haired Girl" character was based on Donna Johnson, a redhead who refused his marriage proposal and married another man. Cartoonist Bill Watterson wrote that in drawing the comic strip Peanuts, Charles Schulz "was able to expose and confront his inner torments through his creative work." After Charles Schulz's drawings were rejected by his high school senior yearbook, he used the incident as inspiration for a Peanuts comic strip involving Snoopy.

Charles Schulz used his Peanuts comic

Because of specialized salt glands on their tongues, some crocodiles are able to live in saltwater habitats, while others live in freshwater. Crocodiles have flexible diets, but if nothing is available to eat, they can survive on stored food for a year. Scientists believe that the Crocodilia order, which includes all modern crocodile species, has been around for about one hundred million years.

Crocodiles have adoptions

the desert

Desert plants have adaptations that enable them to survive despite their limited access to water

The creosote bush can thrive in dry areas like the Sonoran and Mojave Deserts by cloning itself. In Death Valley, some wildflower seeds sprout only when it rains. The Sonoran Desert's velvet mesquite has roots that can extend over fifty yards to water sources.

Desert plants have adoptions

Akira Kurosawa's two films Throne of Blood and Ran were based on William Shakespeare's plays Macbeth and King Lear, respectively. Akira Kurosawa first studied Western art and literature before embarking upon a film career. Akira Kurosawa viewed Fyodor Dostoevsky as an important influence on his work and even created an adaptation of the Russian novelist's book The Idiot.

Director Akira Kurosawa

Dr. Carl Sagan was the co-host and co-writer of Cosmos: A Personal Voyage, a thirteen-part PBS series watched by 750 million people. As an astronomy and space sciences professor at Cornell University, Dr. Carl Sagan edited a scientific journal, published books, and appeared frequently as a guest on late-night talk shows. Dr. Carl Sagan wrote a highly popular companion book for the series Cosmos, as well as the follow-up book Pale Blue Dot: A Vision of the Human Future in Space.

Dr. Carl Sagan was a gifted

By the end of his second year in office, President Franklin Roosevelt had signed into legislation the groundbreaking Social Security Act, which created a pension plan for all Americans and provided workers with unemployment insurance. As part of the New Deal, President Franklin Roosevelt launched the Works Progress Administration (WPA) in spring of 1935, creating thousands of new jobs building highways, schools, and parks. After President Franklin Roosevelt assumed office in 1933, he worked with Congress to quickly pass the Emergency Banking Act, which reorganized banks and closed those that were insolvent.

During his first term as president

In 1846, Emily Brontë published a volume of poetry with her sisters, Charlotte and Anne, and the following year saw the publication of her now-classic novel Wuthering Heights. Charlotte Brontë's acclaimed novel Jane Eyre is still commonly taught in high school English classes. Anne Brontë's novels Agnes Grey and The Tenant of Wildfell Hall, though not as well known as her sisters' major works, were well received.

Each a talented writer in her own

Dmitri Mendeleev created the periodic table for his book The Principles of Chemistry. Dmitri Mendeleev's periodic table contained only sixty elements, but the table was updated as other elements were discovered. Dmitri Mendeleev arranged the elements in order of atomic weight and placed them in rows and columns according to their physical and chemical properties.

In 1969,

From his home in Oakland, California, John Muir wrote popular magazine articles about setting aside U.S. lands and preserving them from development. John Muir believed that there was intrinsic value in wilderness that was untouched by humans. During a three-night camping trip in Yosemite National Park in 1903, John Muir personally persuaded President Theodore Roosevelt to return Yosemite Valley and Mariposa Grove to federal protection.

John Muir, founder of the Sierra Club, sought to preserve land in order to maintain its pristine nature.

Some historians believe that German businessman Augusto Berns looted Machu Picchu four decades before Hiram Bingham visited the site. Hiram Bingham is generally said to have discovered Machu Picchu in 1911, but locals, including farmer Melchor Arteaga who led Bingham there, were already aware of the Incan ruins. Carl Haenel wrote a letter to the New York Times claiming that he had been in Machu Picchu with German explorer J. M. von Hassel a year before Hiram Bingham arrived in the area.

Just who should be

Guide Dogs of America uses Labrador retrievers more than any other breed because they make the most successful service dogs. Labrador retrievers work well for a variety of owners, unlike German Shepherds, which do better with more confident owners. Labrador retrievers are intelligent and friendly.

Labrador retrievers make ideal service dogs because they have the best temperament for working with people

Marie Curie was the first person to receive two Nobel Prizes—one in physics and one in chemistry. Marie Curie was hired as the first female physics professor at the University of Paris. In 1903, Marie Curie became the first woman in France to earn a doctorate degree.

Marie cure achieved

Cosimo de' Medici used his wealth to fund the work of Florence's architects and painters. Lorenzo de' Medici paid humanist John Lascaris and poet Angelo Poliziano to improve the Medici libraries in Florence. Giovanni de' Medici's fortune was used to support many artists in Florence, including Leonardo da Vinci.

Members of the Medici Family

Worker bees are sterile females that search for pollen and nectar and make sure the queen bee's offspring are safe. The queen bee lays eggs and produces a chemical that guides the hive's activities. A hive has one queen bee, about 60,000 worker bees, and hundreds of male drones that try to impregnate the queen bee

Queen bees, worker bees, and drones all have specific functions in their hives

The United Kingdom rebuilt the Halley VI Research Station in Antarctica using stilts. In 1997, South Africa's Sanae IV Research Base in Antarctica was built on stilts because the previous stations were destroyed by the accumulation of drifting snow. Established by the U.S. in 1956, the Amundsen-Scott Pole Station in the Antarctic was designed so that snow would blow beneath it instead of crushing it.

Research stations in the Antarctic must be specially designed to withstand the local environmental conditions.

Arabian traders transported only limited quantities of cinnamon in the Middle Ages, making it expensive in Europe. During the Middle Ages, a host's generosity when providing spices to a guest at a meal was a signal of wealth. Only wealthy European families could afford cinnamon in the Middle Ages.

Since foreign spices

Athletes wore an early version of rubber-soled sneakers called plimsolls in the late eighteenth century. Sneakers gained popularity when many U.S. teenagers embraced the shoe after seeing actor James Dean wear them in the movie Rebel Without a Cause. Rubber sneakers with canvas tops were mostly used in athletics from the time of their creation in 1892 until the 1950s.

Sneakers were created for sports, but they eventually became a fashion statement

Stonefish have rough bodies without scales and avoid predators by blending in with rocks or hiding in crevices in shallow waters. The body of the American stick insect resembles a twig, making it virtually invisible to predators when it remains still. Flounder have speckled skin that camouflages them from predators on the ocean floor and helps them prey on shrimp and worms.

Some animals rely on natural camouflage to conceal themselves from predators.

At Yosemite National Park, visitors are instructed to remove food from their cars; otherwise, bears can cause significant damage by breaking into vehicles. Some California parks require that backpackers keep their food supplies in special bear-proof containers. Campsites are sometimes equipped with specialized waste receptacles intended to keep out bears.

State and national parks

Sailing down rivers, the Vikings were able to travel to Russia and the Middle East and trade with the people living there. The construction of their longboats made it possible for Vikings to sail in deep and shallow waters, thereby allowing them to visit many new areas. Toward the end of the tenth century, Viking explorer Leif Eriksson used a longboat to sail to Vineland in North America.

Thanks to their abilities as shipbuilders and sailors, the Vikings were able to travel far and explore other lands.

Historians, astronomers, mathematicians, and poets from every part of the Hellenistic world were paid by Egyptian kings to study and teach at the museum in Alexandria. Founded around 280 BCE by the Ptolemy dynasty, the Alexandrian Museum provided gardens, banquet halls, and reading rooms where scholars met regularly. The Library of Alexandria, which was part of the Alexandrian Museum, did not have bound books but instead contained 700,000 papyrus scrolls that were arranged in piles.

The Alexandrian Museum was significant as an important center of learning in the ancient world.

The Globe Theatre contained three levels of seating for those willing to pay extra to avoid standing. After 1599, most of Shakespeare's plays could be seen at the Globe, including Hamlet, Macbeth, and King Lear. The Globe Theatre admitted anyone who was able to pay to see Shakespeare's plays performed, including poorer people who, for a mere penny, could stand in the pit in front of the stage.

The Globe Theatre was instrumental in giving the public access to Shakespeare's greatest works.

The Lincoln Memorial attracts about six million tourists annually, making it the most-visited presidential memorial in the U.S. Designed by architect Henry Bacon, the Lincoln Memorial is one of the most recognizable structures in the U.S., and it frequently appears in movies and TV shows. Drawing on its importance as a symbol to the Civil Rights Movement, Martin Luther King, Jr., delivered his "I Have a Dream" speech on the steps of the Lincoln Memorial in 1963.

The Lincoln Memorial is a meaningful

Leonardo da Vinci's Mona Lisa draws millions of visitors each year. The Venus de Milo is one of the Louvre's most well-known sculptures. The Louvre houses the stone pillar on which the ancient Code of Hammurabi is written.

The Louvre, Paris's most famous art museum,

The ancient Olympic Games gave leaders from different Greek city-states a rare opportunity to meet and discuss political and economic issues. Wars between city-states were temporarily suspended during the Olympic Games, and athletes were allowed to travel to and from Olympia freely. Spectators as well as participants in the Olympic Games were encouraged to interact with the citizens of other city-states.

The Olympic Games provided an opportunity

Mumtaz Mahal's tomb, known as the Taj Mahal, is famous for its combination of Persian, Islamic, and Indian architectural styles and for the love story that inspired its construction. The placement of Mumtaz Mahal's and Shah Jahan's sarcophagi was the focus of the Taj Mahal's design. Shah Jahan had the Taj Mahal built to honor his wife after she died giving birth to the couple's fourteenth child in 1631.

The Taj Mahal is a famous mausoleum dedicated to an emperor's love for his wife.

Skiers and snowboarders can take an avalanche safety class to learn how to test snowpack stability, avoid dangerous routes, and use safety equipment. Avalanche forecasts are available from the American Avalanche Association. Skiers and snowboarders can check current weather conditions prior to hitting the slopes.

The best way to reduce the risk

The maniraptoran's size allowed it to have simpler food requirements than larger dinosaurs had. Scientists think that the maniraptoran lived as long as it did because its small size made it possible to adapt to new habitats more easily. Researchers believe the maniraptoran's size allowed it to avoid danger by moving more quickly than larger dinosaurs.

The maniraptoran may have been better suited for survival than larger dinosaurs because of its small size

Smaller railroads connected to the transcontinental opened new lands to settlement and allowed thousands of new towns to be built. The transcontinental railroad allowed access to previously untapped natural resources from the West and Midwest, leading to a boom in U.S. manufacturing. Freight and passengers crossed from the East to the West more quickly and cheaply than ever before once the transcontinental railroad was completed in 1869.

The transcontinental railroad

Add a two- or three-inch layer of decayed leaves and manure to improve the quality of the soil. Plant vegetables in a spot that receives at least six hours of sunlight every day. Choose vegetables that are suited to the climate, consult the seed packet for planting instructions, and water seedlings daily.

To create a thriving vegetable garden, try to ensure optimal conditions for your plants

The male octopus dies after mating, and his partner's body begins to deteriorate as soon as her eggs hatch. Female octopuses tend to be larger and stronger than males. In some documented cases, female octopuses have cannibalized their male partners after mating.

When octopuses come together to mate

Charles Dickens's novel Oliver Twist exposed the cruel treatment that many orphans faced in Victorian England. Charles Dickens wrote frequently about issues such as poverty and the pitfalls of industrialization. During his 1842 lecture tour in the U.S., Charles Dickens spoke out against slavery.

a popular

Marian Anderson was the first black person to perform at New York City's Metropolitan Opera. In 1939, Marian Anderson was refused permission to perform for an integrated audience at Constitution Hall. Eleanor Roosevelt lobbied for Marian Anderson to be allowed to perform at the Lincoln Memorial.

a talented singer

The Greek physician Hippocrates recognized that chewing on willow bark would reduce pain. Thousands of years ago, Chinese medical practitioners began using leaves from gingko biloba trees to improve blood flow to the heart and lungs. The cacao seed is the source of chocolate, but for centuries it has also prevented hypertension in the Kuna people, descendants of the Maya.

ancient civilizations used available

Keep raw meats, seafood, poultry, and eggs away from other foods to prevent cross-contamination of bacteria. Prevent the spread of illnesses caused by bacteria by always washing your hands thoroughly before preparing food. Thaw meats in the refrigerator, not on the counter, where the warmer air allows bacteria to multiply quickly.

by taking precautions

Emergency kits are best stored in cool, dry places with food and water supplies refreshed periodically. A basic emergency kit should include a three-day supply of food and water and a first aid kit. Emergency kits should be available at home, at work, and in cars.

disaster prevalist

Would-be marathon runners must be physically prepared to follow a rigorous training schedule. Training at the race site can help new runners know what to expect from a marathon-length course. Runners attempting their first marathon should have at least one year of running experience.

first-time marathon runners

In ancient Rome, many larger houses included separate cheese kitchens, where dairy products could mature. Pottery remains with ancient dairy residue from 5000 BCE suggest that humans from that time may have kept cows, goats, and sheep in order to make cheese. Wall murals depicting cheesemaking prove that it was part of ancient Egyptian culture.

historical accounts

To recycle a broken umbrella with metal parts, remove the shaft, runner, stretchers, and ribs so that they can be processed with other scrap metal. Rinsed-out metal cans can be recycled by the local sanitation department or a steel-can recycling facility. Older electronics can often be recycled at local drop-off locations and even at some electronics stores.

its possible

Frequently hand washing with warm water and soap is the best way to get rid of germs and prevent illnesses. Moderate exercise boosts the immune system and can reduce the risk of colds by a third. Used sponges and rags should be replaced regularly to avoid spreading harmful bacteria.

simple steps

The Library of Alexandria, which was part of the Alexandrian Museum, did not have bound books but instead contained 700,000 papyrus scrolls that were arranged in piles. Historians, astronomers, mathematicians, and poets from every part of the Hellenistic world were paid by Egyptian kings to study and teach at the museum in Alexandria. Founded around 280 BCE by the Ptolemy dynasty, the Alexandrian Museum provided gardens, banquet halls, and reading rooms where scholars met regularly.

the alexandrian museum

Oceanographer Kathryn Sullivan researched remote sensing prior to joining NASA and becoming the first woman to perform a spacewalk during Challenger's 1984 mission. Selected for her skill as a parachutist, the Soviet Union's first female cosmonaut, Valentina Tereshkova, was launched into space in 1963 on board the Vostok 6. The first American woman to fly in space, physicist Sally Ride, helped to develop the robotic arm used to put satellites into orbit during Space Shuttle Challenger's 1983 mission.

the first women

Modern refrigeration has reduced the number of foodborne illnesses and has allowed fresh foods to be transported long distances. The Royal Society named the refrigerator the most important invention in the history of food, followed by pasteurization, canning, and the oven. Prior to refrigeration, ancient civilizations depended on root cellars, collected ice, salting, and other methods to cool and preserve their foods.

the invention

Venus is similar to Earth in terms of size and mass, but its surface pressure is ninety times higher. Mars has no liquid water on its surface today, though robotic rovers have confirmed that it did at some point in the past. While Venus has surface temperatures that are hot enough to melt lead, the average temperature on Mars is -67°F.

the planets closest

William the Conqueror built the Tower of London after the Norman Conquest in 1066. The Tower of London has served as a political prison, a royal residence, and a place to store weapons, documents, wild animals, and the Crown Jewels of the United Kingdom. Between the fourteenth and seventeenth centuries, the coronation march for British royalty began at the Tower of London.

the tower has played an important

In 1900, André Michelin published the Michelin Guide—a resource for French motorists who were looking for reputable hotels and restaurants during long trips. Édouard and André Michelin used their family rubber business to develop and sell pneumatic tires for bicycles and cars. The Michelin Group started publishing road maps for drivers in 1910.

Édouard and André Michelin launched a range of products aimed at motorists.