Download You have a heart that pumps blood. The blood brings oxygen and

1. You have a heart that pumps blood. The blood brings oxygen and nutrients to every
part of your body. This gives you energy. The Amazing Human Body, Ruby J. Jameson
2. Your bones are like the framework of a building. Without a framework, the building
would collapse. Bones: Our Skeletal System, Seymour Simon
3. Without a skeleton, your body would be nothing more than a heap of muscles and soft
tissue. If you didn’t have bones, you wouldn’t be able to stand, walk or run. Bones: Our
Skeletal System, Seymour Simon
4. You need oxygen to live. As you breathe in, your lungs fill up with oxygen-rich air. The
air passages in your lungs take the oxygen into your body. The air that you breathe out
is called carbon dioxide. As you breathe out, your body gets rid of unwanted carbon
dioxide. How Your Body Works: A Good Look Inside Your Insides, David Stewart
5. The circulatory system works with other systems and organs in your body. It delivers
food, chemicals, and fluids to cells throughout your body. It helps rid your body of
waste. It carries cells that fight disease. If your circulatory system stopped working,
your cells would starve. You would soon die. How Your Body Works: A Good Look
Inside Your Insides, David Stewart
6. The heart has a left side and a right side. Blood enters the heart from the body on the
right side. Then it goes from the right side of the heart to the lungs. There it picks up
oxygen. It returns to the left side of the heart. The oxygen-rich blood is then pumped to
the body. The heart contains valves. The valves keep the blood flowing in one
direction. . How Your Body Works: A Good Look Inside Your Insides, David Stewart
7. Muscles make up about 40% of a normal person’s body weight. Fat, by contrast, makes
up only about 10%. Muscles, Our Muscular System, Seymour Simon
8. Muscles can only pull, so they work in pairs. In your arm, the bicep pulls by contracting
to bend the arm and the tricep pulls to straighten it. As a muscle contracts, it gets
shorter and harder. As a muscle relaxes, it gets longer and softer. Eye Wonder: Human
Body
9. We are all swimming in air. Air covers our entire planet in a thick blanket. The basic
problem is that the oxygen that your body needs inside is outside, and the waste your
body needs outside is inside. So how does your body get these things where they need
to be? By now you know the answer: your respiratory system moves them. The
Insiders Guide to the Body: The Respiratory System, Justin Lee
10. Exercise doesn’t give you more muscles, but it strengthens the muscles you have and
helps keep them working well. Without exercise, muscles shrink and tire easily. This
can happen if you are ill and unable to exercise for a long time. Muscles, Our Muscular
System, Seymour Simon
11. As blood travels through the lungs, it picks up oxygen. This makes it brighter in color.
As it releases oxygen around the body, it grows darker. Eye Wonder: Human Body
12. Have you ever been so tired that your muscles actually ached from fatigue? Remember
how walking up the stairs to your bed seemed like such a long journey, how it felt as
though would never ever get there? Think about how many times you have woken up
late for school and had to catch the bus. Human beings depend on their muscles, but
your muscles also depend on you. Taking care of your muscles is incredibly important
because your muscles will only do their jobs well if they get what they need: food for
energy, rest to recover, and exercise to keep them strong. The Insider’s Guide to the
Body: The Muscular System, Katherine White
13. The human body contains hundreds of different parts, such as the stomach, intestines,
liver, kidneys, brain, bones, muscles and heart. Each has its own tasks to do. However,
all the parts must work together in a controlled and coordinated way, so that the body
can function as a whole and stay healthy. Spinal Cords and Nerves, Steve Parker
14. In some ways, the body’s nervous system is similar to the communication systems you
use daily to make phone calls, send e-mails, and surf the Internet. The nervous system
as well as communication systems, are designed in the form of a network, with millions
of senders, receivers and connections. These systems work to send information or
messages from one place to another. Messages travel in the form of tiny electrical
signals or pulses, along bundles of long, wire-like structures. In these systems, there are
parts called relay stations, which pass messages on to their destination. . Spinal Cords
and Nerves, Steve Parker
15. Every city has a road network of big highways, main streets and smaller roads. These
are busy with vans and trucks delivering supplies to factories, schools and other places.
There are also garbage trucks, gathering the waste and trash. Your body’s network of
blood vessels is like the city’s road systems. It provides routes all around the body for
delivery of oxygen and nutrients and collection of wastes. Pump It Up: Respiration and
Circulation, Steve Parker
16. The muscles in your esophagus use a rippling motion to move the food along. This
rippling motion is called peristalsis. Here is how it works:
1. First, the upper muscles in the esophagus squeeze. This action forces the
food down toward the stomach.
2. The next group of muscles in line squeezes to force the food down further.
3. Then the next group of muscles in line squeezes and forces the food down
even more.
4. This motion goes on until the food reaches your stomach.
The Dynamic Digestive System: How Does My Stomach Work?
17. The action of breathing is controlled by the diaphragm. During inhalation, the
diaphragm contacts, pulling downwards and enlarging the chest. During exhalation the
diaphragm relaxes, making the chest cavity smaller. The increase in the size of the chest
cavity reduces the pressure inside the lungs. Air then moves inwards towards the lungs.
As the pressure in the chest cavity rises, the air in the lungs flows outwards. Our Body:
Respiratory System, Cheryl Jakab
18. Your heart is a hard worker, and it never stops for a rest. It is made of muscle filled with
blood. Two pumps keep this blood moving. The one on the right squeezes blood into
the lungs. Here the blood picks up oxygen and returns to the heart. The left pump then
forces the blood out into arteries and around the body. When the blood gets back, the
heart sends it on another round trip. Every Body Tells A Story, Robert Coupe
19. If one part of a car’s engine is faulty, the engine won’t work properly, or may not work
at all. Like a machine, your body needs all its parts to work if it is to stay healthy.
Different parts combine with each other to do special jobs. For example, your stomach,
liver, intestines, and some other organs all help your body digest food and get rid of
wastes. These organs are called your digestive system. There are ten of these systems
in your body. Some are very small. Others spread widely through the body. All of them
are important. Every Body Tells A Story, Robert Coupe
20. When you eat, your food starts on a journey. It begins in your mouth, where you chew
it and mix it with saliva. When the food is small and soft enough, your tongue forces it
to the top of your mouth and then down into your throat. From there, it goes down a
tube, called the esophagus, into your stomach. A small flap, the epiglottis, closes your
windpipe, or trachea, to stop you from choking. When the food reaches your stomach,
muscles squeeze it and break it down even more. Then the food continues on its
journey to the small intestine. Here the nutrients pass into the bloodstream. The rest
of the food moves on to the large intestine, and from there to the rectum, and then to
the anus. From there the remaining wastes pass out of the body. Every Body Tells A
Story, Robert Coupe
21. The heart is connected to all parts of the body by tiny tubes called veins and arteries.
Veins and arteries are like one-way streets. The veins carry blood toward the heart, and
the arteries carry blood away from the heart. To pump blood, the heart contracts
(makes itself smaller) and expands (gets bigger). It is a little like a hand making a fist and
then relaxing, over and over again. When the heart contracts, blood is pushed out of
the heart and into the arteries. When it expands, blood trickles back in from the veins.
The Heart, Anne Fitzpatrick
22. A bundle of neurons is called a nerve. Nerves are the body's wiring. They carry tiny
electrical-chemical signals called nerve impulses. Nerves branch out from the brain and
spinal cord to your eyes and ears, your stomach, skin, bones and even inside your teeth.
The thinnest nerves are narrower than a hair. The thickest nerves look like pieces of
white rope. A single nerve cell has a central cell body, branching threads called
dendrites, and a long wirelike axon. The dendrites carry electrical signals toward the cell
body, while the axon carries the signal away. The Brain: Our Nervous System Seymour
Simon
23. When your finger touches something hot, signals from touch sensors in your skin travel
along sensory nerves at speeds of up to four hundred feet a second. In a split second,
the signals reach relay nerves in your spinal cord and then transfer to other nerves that
go to your brain, which 'feels' the touch. Your brain then sends out messages to your
spinal cord and then to motor nerves. Motor nerves carry messages to muscle cells that
make your arm move. The Brain: Our Nervous System Seymour Simon
24. Your skull is made up of twenty-eight bones. Eight of the bones fit together like pieces
of a jigsaw puzzle. They form a strong eggshell shape that protects the brain. These
bones make up your braincase, or cranium. The other twenty bones help shape your
jaws and face. Inside the skull, the brain sits in a liquid bath that helps protect and
cushion it against shocks. A human brain is about the size of a large grapefruit and
weighs about three pounds when fully grown. It looks like a wrinkled blob of pinkish
gray jelly. The Brain: Our Nervous System Seymour Simon
25. In a way, your stomach is like a reverse factory. Think about it. Factories take in raw
materials like metal. Then they make complex items like cars. Your stomach takes in
complex items. (What, you say? You don't think food is so complicated? Just picture all
the different ingredients in a burger loaded with cheese, mustard, ketchup, pickles, and
onions). Then the stomach makes raw materials like vitamins and protein. Rumble and
Spew: Gross Stuff in Your Stomach and Intestines, Sandy Donovan
26. Last, but not least, the circulatory system acts as your personal bodyguard. White blood
cells destroy harmful invaders. Platelets seal up wounds so you don't lose too much
blood. This team of defenders keeps your body healthy and safe. The Circulatory
System, Susan Glass
27. When you chew your food, your teeth grind it into a saliva-soaked paste.
MMMM...DELICIOUS! Then your tongue helps push the mushed-up food down
your throat. After the throat, the food travels on through a tube called the esophagus.
Right at the end of the esophagus is a muscle called the sphincter. The ring-shaped
muscle lets food into the stomach. Once the food has passed through, the muscle
squeezes shut to keep it from coming back the other way. Rumble and Spew: Gross
Stuff in Your Stomach and Intestines, Sandy Donovan
28. Eating junk food may taste good, but it isn't good for your circulatory system. Junk food
is high in calories, salt, sugar and fat. All of these things can contribute to heart disease.
Eating too much junk food can also lead to being overweight. Extra weight puts a strain
on your heart. Instead of eating junk food, try eating dairy products that are lower in
fat, llean meats, whole grains, fruits and vegetables. These foods make your heart
happy. The Circulatory System, Susan Glass
29. Standing and moving around are second nature to most people. We don't think about
it, in the same way that we don't have to think about what shape our body is as we go
to school or run down the street. Yet without our skeletons and muscles, we would be
shapeless blobs, and we wouldn't be able to move! Body Systems and Health, Ann
Fullick
30. The skeleton and the muscles both respond to exercise. When you walk and run, it
builds up the bone in your skeleton. The muscles are the same. The more you exercise
and use them, the more they grow and the stronger they get. Body Systems and Health,
Ann Fullick