Working together
When you make complicated movement, such as running and jumping, you use many different muscles at the same time. Leg muscles push you along, arm muscles help you to stay balanced, and muscles in your back hold your body upright. Continual repetition of a movement decelops your ability to make all these muscles work together.
Making faces
You have more than 40 different muscles in your face. You use them all the time when you are awake, and sometimes when you are asleep. They help you to speak, eat, and blink, and they also enable you to alter your expression. For humans, facial expressions are very important, because they allow us to show oyher people how are we sleeping. Babies know how to smile and laugh, but we learn many other expressions as we grow up. Try making faces at a friend, and see how many different feelings you can communicate without using words.
Saturday, November 17, 2007
Can we control all our muscles?
You can control nearly all of the skeletal muscles. the one attached to your bones. You can control some of the muscles that work other parts of your body, such as the one you use to swallow, and those you use to make faces. You also have muscles, such as those in your eyes and digestive system, that work without your telling them to.
Running
Each time you take a stride, powerful muscles in the back of your thighs and calves press your feet and toes againts the ground, levering your body forwards. Muscles on the front of your thighs lift your legs.
Closing up
When bright light shine in your eyes, muscles inside your eyes automatically make your pupils smaller to reduce the amount of light getting in.
In the air
Muscles in your shoulder and upper arm ruse and bend your arms to help you stay balanced when your body is off the ground. Muscles in your thighs raise your legs and keep them bent.
Landing
Thigh muscles hold your legs steady, with knees and ankles bent, ready to take the force of the impact with the ground. At the same time, muscles on the front of your body tighten up, keeping your stomach and intestines in place as you suddenly come to a halt.
Tired out
Athletes push themselves very hard during competition and their leg muscles take time to stop aching.
You can control nearly all of the skeletal muscles. the one attached to your bones. You can control some of the muscles that work other parts of your body, such as the one you use to swallow, and those you use to make faces. You also have muscles, such as those in your eyes and digestive system, that work without your telling them to.
Running
Each time you take a stride, powerful muscles in the back of your thighs and calves press your feet and toes againts the ground, levering your body forwards. Muscles on the front of your thighs lift your legs.
Closing up
When bright light shine in your eyes, muscles inside your eyes automatically make your pupils smaller to reduce the amount of light getting in.
In the air
Muscles in your shoulder and upper arm ruse and bend your arms to help you stay balanced when your body is off the ground. Muscles in your thighs raise your legs and keep them bent.
Landing
Thigh muscles hold your legs steady, with knees and ankles bent, ready to take the force of the impact with the ground. At the same time, muscles on the front of your body tighten up, keeping your stomach and intestines in place as you suddenly come to a halt.
Tired out
Athletes push themselves very hard during competition and their leg muscles take time to stop aching.
Friday, November 16, 2007
MUSCLES AND MOVEMENT
Our muscles are bundles of fibres that alternately shorten and relax to make parts of the body move. They make up more than half your body's weight. Muscle enable you to walk, run, breathe and blink, and they keep your body in position when you sit or stand. Some muscles, such as the biceps in your arms work only when you want them to. Others, such as your heart, never stop walking.
How do muscles work?
Muscles are made up of millions of cells called muscle fibres, which contain overlapping chemical threads. When a muscle receives signals from the nervous system, the thread slide closer together, making the whole muscle shorten or contract. This moves the part of the body to which the muscle is attached. See also the muscle basic and the listing of muscles names at http://www.jdenuno.com/6~Muscles.htm
How do muscles work?
Muscles are made up of millions of cells called muscle fibres, which contain overlapping chemical threads. When a muscle receives signals from the nervous system, the thread slide closer together, making the whole muscle shorten or contract. This moves the part of the body to which the muscle is attached. See also the muscle basic and the listing of muscles names at http://www.jdenuno.com/6~Muscles.htm
Joints
Joints are the place where bones are connected. In the joints that enable different parts of your body to move - for example, your shoulder, elbow, hips and knees - the bones are tipped with smooth cartilage. This is made slippery by an oily fluid so that the bones can slide over each other. In other joints, particularly ones in your skull, neighbouring bones are firmly locked together. This ensure that these parts of the skeleton stay in exactly the right position.The hip joint is shaped so that the thighbone can swivel in many different directions. In the skull, zigzag joints keep bones locked together so they cannot move. This protects the brain.
Joints are the place where bones are connected. In the joints that enable different parts of your body to move - for example, your shoulder, elbow, hips and knees - the bones are tipped with smooth cartilage. This is made slippery by an oily fluid so that the bones can slide over each other. In other joints, particularly ones in your skull, neighbouring bones are firmly locked together. This ensure that these parts of the skeleton stay in exactly the right position.The hip joint is shaped so that the thighbone can swivel in many different directions. In the skull, zigzag joints keep bones locked together so they cannot move. This protects the brain.
Thursday, November 15, 2007
largest and small bones
The biggest bone in the human body is the thigh bone, or femur. In an average man, it is about 45 cm (18 in) long. The end of a thigh bone contain lots of small spaces filled with marrow cells, which help to save weight. Without these space, moving about would be hard work because the bone would be very heavy.
The smallest bone is the stirrup, inside the ear. It is just 5 mm (1/5 in) long and helps to carry sounds into the inner part of the ear. There are three bones in each ear, and they are so small that they would all fit inside a matchbox.
In an adult, the thigh bone can weigh over 200 000 times as much as the stirrup bone hidden away in the inner ear.
How many bones are there in my body?
It dependshow old you are. At birth, a lot of the skeleton is made of a rubbery substance called cartilages. As you grow older, most of this turns to bone. Then some bones start to join up. For example, two bones that form your forehead grow together soon after birth. In your mid-teens, five bones near the base of your spine start to form a single bone called the sacrum. By your mid-twenties, you will have about 206 bones.
The biggest bone in the human body is the thigh bone, or femur. In an average man, it is about 45 cm (18 in) long. The end of a thigh bone contain lots of small spaces filled with marrow cells, which help to save weight. Without these space, moving about would be hard work because the bone would be very heavy.
The smallest bone is the stirrup, inside the ear. It is just 5 mm (1/5 in) long and helps to carry sounds into the inner part of the ear. There are three bones in each ear, and they are so small that they would all fit inside a matchbox.
In an adult, the thigh bone can weigh over 200 000 times as much as the stirrup bone hidden away in the inner ear.
How many bones are there in my body?
It dependshow old you are. At birth, a lot of the skeleton is made of a rubbery substance called cartilages. As you grow older, most of this turns to bone. Then some bones start to join up. For example, two bones that form your forehead grow together soon after birth. In your mid-teens, five bones near the base of your spine start to form a single bone called the sacrum. By your mid-twenties, you will have about 206 bones.
Type of bones
Skull (cranium)
The skull of an adult contains more than 20 bones, but only one of them - the jawbone, also called the mandible - can move.
Shoulder blade (scapula)
This forms the back of the shoulder.
Backbone or spine
This hold the skeleton together, and is made up to 33 bones known as vertebrae. Most of these can move so that the backbone can bend.
Floating ribs
Most ribs are attached to the spine at the back, and to the breastbone at the front. the lowest two pairs are different, because their front ends are not attached to anything. That is why they are known as floating ribs.
Thigh bone (femur)
Like all bones, the thigh bone contains marrow, a jelly-like substance that makes blood cells.
Arm
Each arm has a single upper-arm bone called the humerus, and two lower-arm or forearm bones, called the radius and the ulna. The forearm bones can swivel to turn the hand.
Rib cage
The ribs form a flexible box around the lungs that changes shape to allow the lungs to expand when you breathe in. Most people have 12 pairs of ribs, but about one person in 20 has 13 pairs.
Breastbone (sternum)
This support the front of the rib cage.
Hip bone (pelvis)
This bony ring links the legs to the backbone.
Scranum
This forms the back of the pelvic girdle.
Kneecap (patella)
This small bone protects the knee against injury. It is held in place by tough cords called
tendons.
Foot
Each of feet contains 26 bones-one fewer than each hand.
The skull of an adult contains more than 20 bones, but only one of them - the jawbone, also called the mandible - can move.
Shoulder blade (scapula)
This forms the back of the shoulder.
Backbone or spine
This hold the skeleton together, and is made up to 33 bones known as vertebrae. Most of these can move so that the backbone can bend.
Floating ribs
Most ribs are attached to the spine at the back, and to the breastbone at the front. the lowest two pairs are different, because their front ends are not attached to anything. That is why they are known as floating ribs.
Thigh bone (femur)
Like all bones, the thigh bone contains marrow, a jelly-like substance that makes blood cells.
Arm
Each arm has a single upper-arm bone called the humerus, and two lower-arm or forearm bones, called the radius and the ulna. The forearm bones can swivel to turn the hand.
Rib cage
The ribs form a flexible box around the lungs that changes shape to allow the lungs to expand when you breathe in. Most people have 12 pairs of ribs, but about one person in 20 has 13 pairs.
Breastbone (sternum)
This support the front of the rib cage.
Hip bone (pelvis)
This bony ring links the legs to the backbone.
Scranum
This forms the back of the pelvic girdle.
Kneecap (patella)
This small bone protects the knee against injury. It is held in place by tough cords called
tendons.
Foot
Each of feet contains 26 bones-one fewer than each hand.
Wednesday, November 14, 2007
BONES AND SKELETONS
Flexible framework body
Bones support your body, make up about one-fifth of your total weight. Without them, you would not be able to move, to eat, or even to breathe. Bones change as you grow up, and they also get thicker and stronger if they have to do a lot of extra work or carry extra weight. Together, they make a flexible framework for your body. Some bones have a Latin name as well as an English name.
What are bones made of?
The human skeleton is made up of bones of many shapes and sizes. About one-tenth of all the bones in your body form your skull, while more than half are crammed into your hand and feet. Some bone, such as the shoulder blades, are thin and flat, but most of the bigger bones are long and hollow.Nearly two-thirds of a bone's weight is made up by crystal of a mineral called calcium phosphate. The other third is made up by fibres of a substance called collagen. The crystals and fibres are produced by bone cells, which are scattered throughout the bone. Tiny channels running through the bone allow blood to reach the bone cells.
Inside a bone
This a part of a section through a bone, magnified around 100 times. The rings are made of mineral crystal. Fibre and bone cells live in the small gaps between the rings. The mineral crystals give a bone its strength, while the fibres help it to bend without breaking.
Bones support your body, make up about one-fifth of your total weight. Without them, you would not be able to move, to eat, or even to breathe. Bones change as you grow up, and they also get thicker and stronger if they have to do a lot of extra work or carry extra weight. Together, they make a flexible framework for your body. Some bones have a Latin name as well as an English name.
What are bones made of?
The human skeleton is made up of bones of many shapes and sizes. About one-tenth of all the bones in your body form your skull, while more than half are crammed into your hand and feet. Some bone, such as the shoulder blades, are thin and flat, but most of the bigger bones are long and hollow.Nearly two-thirds of a bone's weight is made up by crystal of a mineral called calcium phosphate. The other third is made up by fibres of a substance called collagen. The crystals and fibres are produced by bone cells, which are scattered throughout the bone. Tiny channels running through the bone allow blood to reach the bone cells.
Inside a bone
This a part of a section through a bone, magnified around 100 times. The rings are made of mineral crystal. Fibre and bone cells live in the small gaps between the rings. The mineral crystals give a bone its strength, while the fibres help it to bend without breaking.
INTRODUCTION
The human body is the entire physical structure of a human organism. The human body consists of tissues and cells and also consists of a head, neck, torso, two arms and two legs. Below is a list of the main title of the human body system :
- Bones and skeleton
- Muscles and movement
- Blood and circulation
- Lungs and breathing
- Skin, hair and nails
- Brain and nervous system
- Sound and vision
- Taste, smell, touch and balance
- Teeth
- Digestion
- Getting rid of waste
- Hormones
- Reproduction
- Genes and heredity
- Growing up
- Immune system
- Food and nutrition
- Medical diagnosis
- Medical treatment
- Surgery
Besides know about info about how we work, health and nutrition also the major of diseases.
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