Viral evolution
Tiny germs can change. They change to stay alive. This helps them move fast. It can make them hard to stop. They change in many ways. Do you want to learn more?
Early Reader · Change the reading level on the articleLife Science articles — Page 113
Read about living things, from cells and plants to animals and the human body. Choose an article below; its reading controls let you move between the available levels.
5,533 public articles · Page 113 of 116
Explore related Science Lab activities about plants, animals and ecosystems or the human body, each at five reading levels.
Vireo
These are small birds. They are often green. They live in forests. They eat bugs and fruit. They sing sweet songs. Can you hear them?
Early Reader · Change the reading level on the articleVirginia E. Johnson
Virginia was a smart worker. She studied how bodies work. She worked with a team. This helped many people. Her work was very big. Do you like to learn new things?
Early Reader · Change the reading level on the articleVirginia opossum
The opossum is a gray animal. It is the size of a cat. It likes to come out at night. It eats many kinds of food. This helps it live in many places. Have you seen one?
Early Reader · Change the reading level on the articleVirology
Some tiny things can make us sick. They are too small to see. Scientists study these tiny things. This helps us stay healthy. We can learn a lot! Do you want to learn more?
Early Reader · Change the reading level on the articleVirus latency
Some tiny germs hide in our bodies. They do not make us sick right away. They stay very still and quiet. They can wake up later. This helps them stay inside us. Do you know about tiny germs?
Early Reader · Change the reading level on the articleViscacha
The viscacha is a small animal. It looks like a rabbit. It lives in South America. Some live in big groups. They eat plants to grow. They are fun to see! Do you like rabbits too?
Early Reader · Change the reading level on the articleVisual acuity
Your eyes help you see. They see small things clearly. Some eyes see far away well. Some eyes see things close up well. We can use glasses to help. Do you like to see clearly?
Early Reader · Change the reading level on the articleVisual cortex
Your brain helps you see. It takes in what your eyes see. This part of your brain is in the back. It helps you know what things are. It also helps you find where they are. Can you see the world around you?
Early Reader · Change the reading level on the articleVital signs
Doctors check how your body works. They check how warm you are. They feel your heart beat. They check how you breathe. This helps them keep you well. Do you know your heart rate?
Early Reader · Change the reading level on the articleVitamin A
Your body needs a special kind of food. It helps you see in the dark. It also helps you grow strong. This food is in many things we eat. It keeps your eyes healthy. Can you eat healthy foods today?
Early Reader · Change the reading level on the articleVitamin B12
Some food helps our bodies work. It helps our blood stay healthy. It also helps our brain. We get it from meat and eggs. You can find it in cereal too. It helps you grow strong. Do you eat eggs for breakfast?
Early Reader · Change the reading level on the articleVitamin B3
Our bodies need a special food. This food helps us stay well. It is in meat and fish. It is in some bread too. We need it to live. Do you eat good food?
Early Reader · Change the reading level on the articleVitamin B6
Our bodies need a special helper. This helper comes from food. You can find it in fish and meat. It helps our bodies work well. We get it from what we eat. Do you like to eat fish?
Early Reader · Change the reading level on the articleVitamin D
Sunlight helps your body stay strong. It makes a special thing in your skin. You can also get it from food. This helps your bones stay healthy. It is good for you! Do you like the sun?
Early Reader · Change the reading level on the articleVitamin E
Some foods help our bodies. You can find them in nuts. They are also in seeds. This helps us stay well. It is good for you! Do you like eating nuts?
Early Reader · Change the reading level on the articleVitamin K
This helps your blood. It helps stop bleeding. You can find it in green leaves. It also comes from eggs. Eating good food helps you. Do you like green food?
Early Reader · Change the reading level on the articleVitellaria
The shea tree grows in Africa. It has fruit like big plums. The seeds inside make fat. This fat is used for food. It is also used for skin. People love this tree. Do you like shea butter?
Early Reader · Change the reading level on the articleVitiligo
Some skin can turn pale. These spots can be anywhere. They might be on hands or face. It happens when skin loses color. It is okay to be you. Do you see any spots?
Early Reader · Change the reading level on the articleVitreous body
A clear gel fills your eye. It is like soft jelly. This gel helps your eye stay round. It sits behind your lens. It helps you see the world. Do you see spots in your eyes?
Early Reader · Change the reading level on the articleViverridae
Some animals are called civets. They live in many warm places. They have rough tongues. These tongues have tiny prickles. They use them to eat. Do you want to see them?
Early Reader · Change the reading level on the articleViviparous brotula
These fish live in the sea. Most of them have live babies. They can look like small tadpoles. Some live in deep, dark water. Some even live in caves. They are very cool to see! Do you like fish?
Early Reader · Change the reading level on the articleViviparous lizard
This is a small lizard. It can live in very cold places. It eats bugs like flies and spiders. Some lizards give birth to live babies. This helps them live in the cold. Do you like lizards?
Early Reader · Change the reading level on the articleVoay
A big crocodile lived on an island. It had two horns on its head. This animal was very large. It is gone now. We found its bones in the dirt. Do you like big animals?
Early Reader · Change the reading level on the articleVocal sac
Male frogs have a skin pouch. It helps them make loud sounds. The air goes into the pouch. This makes the call go far. It helps them find friends. Can you hear a frog call?
Early Reader · Change the reading level on the articleVole
A vole is a small animal. It looks like a mouse. It likes to eat plants. They live in holes in the ground. They can be very helpful to the dirt. Do you like small animals?
Early Reader · Change the reading level on the articleVolvariella volvacea
A straw mushroom is a small food. It grows on rice straw. People eat them in many meals. They can be fresh or dried. They taste very good! Do you like mushrooms?
Early Reader · Change the reading level on the articleVombatiformes
Some animals are close kin. They live in a big group. Koalas are in this group. Wombats are in this group too. Many of their old friends are gone. They were very large long ago. Can you find a koala?
Early Reader · Change the reading level on the articleVomiting
Sometimes your body throws up. This happens when your stomach is upset. It pushes food out through your mouth. You might feel sick first. This is called feeling queasy. It helps your body feel better soon. Have you…
Early Reader · Change the reading level on the articleVulture
Vultures are big birds. They look for dead animals to eat. This helps keep the land clean. They have bare heads. This helps them stay clean while they eat. Do you like birds?
Early Reader · Change the reading level on the articleWagtail
Wagtails are small birds. They live in many places. They like to eat bugs on the ground. These birds move their tails a lot. It looks like they are waving. Do you like to watch them wag?
Early Reader · Change the reading level on the articleWakefulness
You are awake when you see the world. It is the opposite of sleep. Your brain works hard while you are up. Being awake helps you learn and play. It is a busy time for your head. Do you feel awake now?
Early Reader · Change the reading level on the articleWallaby
A wallaby is a small animal. It looks like a kangaroo. It lives in Australia. It eats grass and leaves. It has strong legs for jumping. Do you like to jump too?
Early Reader · Change the reading level on the articleWallaroo
A wallaroo is a large animal. It lives in Australia. It is bigger than a wallaby. It is smaller than a kangaroo. These animals are fun to see. Do you like animals?
Early Reader · Change the reading level on the articleWallcreeper
This bird lives in high mountains. It has bright red wings. The wings have white spots. It eats bugs from rocks. It can be hard to see. Do you like bright colors?
Early Reader · Change the reading level on the articleWalter Baldwin Spencer
A man named Walter studied nature. He lived a long time ago. He worked with many animals. He also studied people. He wanted to learn how things work. Do you like to learn about animals?
Early Reader · Change the reading level on the articleWarm-blooded
Some animals stay warm inside. Their bodies make heat. This heat stays the same. It helps them live. This is very cool. Do you feel warm too?
Early Reader · Change the reading level on the articleWart
Warts are small bumps on the skin. They can grow on hands or feet. A tiny germ causes them. Most warts go away on their own. They do not hurt much. Have you ever seen a wart?
Early Reader · Change the reading level on the articleWarthog
Warthogs are a kind of pig. They live in Africa. They have hair on their backs. Some have big teeth. They eat plants and small things. They are very interesting to see. Do you like pigs?
Early Reader · Change the reading level on the articleWASH
Clean water helps us stay well. It helps keep us safe. We use it to stay clean. This helps our whole world. It is good for you. Do you wash your hands?
Early Reader · Change the reading level on the articleWashingtonia filifera
This is a fan palm tree. It grows in the hot desert. Its leaves look like big fans. It has white threads that look like cotton. Many animals live in these trees. Do you like palm trees?
Early Reader · Change the reading level on the articleWater beetle
Some beetles live in the water. They swim and find food there. Some eat green plants. Others eat tiny fish. They can carry air under them. This helps them breathe. Do you like to swim?
Early Reader · Change the reading level on the articleWaterborne disease
Bad germs can live in water. They can make us sick. We get sick if we drink it. We can also get sick when we wash. It is good to have clean water. This helps us stay well. Do you like clean water?
Early Reader · Change the reading level on the articleWatercress
Watercress is a green plant. It grows in the water. It has hollow stems. People eat it for food. It tastes a bit sharp. Do you like green food?
Early Reader · Change the reading level on the articleWater deer
The water deer is a small deer. It lives near rivers and swamps. This deer has long teeth like tusks. It can swim very well. It does not have antlers on its head. Do you like to swim too?
Early Reader · Change the reading level on the articleWater dog
Some dogs love to swim. These dogs have thick hair. Their hair keeps them warm. They help people find things in water. They are very active dogs. Do you like to swim too?
Early Reader · Change the reading level on the articleWater kingfisher
These birds love to eat fish. They live near the water. Some are green. They fly in many places. We can see them hunt. Do you like to watch birds?
Early Reader · Change the reading level on the articleWattieza
These were the first trees. They grew very tall. They did not have leaves. They had soft green parts. They lived a long time ago. They help us learn about the past. Can you imagine a forest like this?
Early Reader · Change the reading level on the article