Potassium Diet is a Healthy Diet

Potassium is a mineral involved in electrical and cellular body functions. In the body, potassium is classified as an electrolyte. Potassium is a dietary mineral that is generally quite abundant in most people's diets, so most healthy people get plenty from their diets. Due to illness, however, some people need to restrict their dietary potassium intake and some people may actually need to increase their intake.

Function

Potassium is a very important mineral to the human body. It has various roles in metabolism and body functions and is essential for the proper function of all cells, tissues, and organs:

• It assists in the regulation of the acid-base balance.
• It assists in protein synthesis from amino acids and in carbohydrate metabolism.
• It is necessary for the building of muscle and for normal body growth.
• It is essential for the normal electrical activity of the heart.

Food Sources

Many foods contain potassium. All meats (red meat and chicken) and fish such as salmon, cod, flounder, and sardines are good sources of potassium. Soy products and veggie burgers are also good sources of potassium.

Vegetables including broccoli, peas, lima beans, tomatoes, potatoes (especially their skins), sweet potatoes, and winter squashes are all good sources of potassium.

Fruits that contain significant sources of potassium include citrus fruits, cantaloupe, bananas, kiwi, prunes, and apricots. Dried apricots contain more potassium than fresh apricots.

Milk and yogurt, as well as nuts, are also excellent sources of potassium.

People on dialysis for kidney failure should avoid consuming too many of these potassium-rich foods. These people require specialized diets to avoid excess potassium in the blood.

Side Effects

Having too much or too little potassium in the body can have very serious consequences.

Because so many foods contain potassium, too little potassium (potassium deficiency) is rarely caused by inadequate diet. However, even a moderate reduction in the body's potassium levels can lead to salt sensitivity and high blood pressure. The recommended dietary intake of 4.7 gm or higher can slightly lower blood pressure.

A deficiency of potassium (hypokalemia) can happen in people with certain diseases or as a result of taking diuretics (water pills) for the treatment of high blood pressure or heart failure. Additionally, many medications -- such as diuretics, laxatives, and steroids -- can cause a loss of potassium, which occasionally may be very severe. You should have your blood levels of potassium checked from time to time if you take any of these medicines. Diuretics are probably the most common cause of hypokalemia.

A variety of conditions can cause potassium loss from the body. The most common are vomiting and diarrhea. Several rare kidney and adrenal gland disorders may also cause low potassium levels.

Too much potassium in the blood is known as hyperkalemia. Some common causes of this are reduced renal (kidney) function, an abnormal breakdown of protein, and severe infection. The most common cause of hyperkalemia is reduced kidney function, especially in people receiving dialysis for kidney failure. Certain medicines affect the body's ability to get rid of potassium. These include potassium sparing diuretics and angiotensin converting enzyme (ACE) inhibitors.

Recommendations

The Food and Nutrition Center of the Institute of Medicine has established the following recommended dietary intakes for potassium:

Infants

0 - 6 months: 0.4 grams a day (g/day)

7 - 12 months: 0.7 g/day

Children and Adolescents

1 - 3 years: 3 g/day

4 - 8 years: 3.8 g/day

9 - 13 years: 4.5 g/day

14 - 18 years: 4.7 g/day

Adults

Age 19 and older: 4.7 g/day

Women who are producing breast milk need slightly higher amounts (5.1 g/day). Ask your doctor what amount is best for you.

Persons who are being treated for hypokalemia need potassium supplements. Your health care provider will develop a supplementation plan based on your specific needs.

Potassium in Foods

If your potassium levels are too high, you doctor may tell you to go on a potassium-restricted diet. If your potassium levels are too low, your doctor may tell you to get more potassium in your diet. Here is a list of foods rich in potassium:

• raisins
• prunes
• apricots
• dates
• strawberries
• bananas
• watermelon
• cantaloupe
• citrus fruits
• beets
• greens
• spinach
• tomatoes
• mushrooms
• soy products
• veggie burgers
• peas
• beans
• turkey
• fish
• beef
• salmon
• cod

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Calcium Rich Foods

According to the American Academy of Pediatrics, "The average dietary intake of calcium by children and adolescents is well below the recommended levels of adequate intake." This can mean that these children will not develop their optimal bone mass, which can put them at risk of fractures and osteoporosis.

Understanding which foods are high in calcium can help you ensure that you are encouraging your kids to get enough calcium in their diet by choosing calcium rich foods such as milk, cheese, and yogurt. Remember that children should eat 3 age-appropriate servings of dairy products per day (4 servings per day for adolescents) or the equivalent to get enough calcium in their diet.

Daily Calcium Needs

It is also important to understand how much calcium kids actually need. The Food and Nutrition Board of the National Academy of Sciences recommends:

• 500 mg a day for kids who are 1 to 3 years old
• 800 mg a day for kids who are 4 to 8 years old
• 1,300 mg a day for kids who are 9 to 18 years old

Keep in mind that calcium's percent Daily Value (% DV), which is a guide to how much of a particular nutrient you should get each day, on food labels is based on the adult requirements of 1000 mg a day. So a cup of milk that was 30% DV for calcium, would be equal to 300 mg of calcium, which would actually be equal to 60% of a toddler's calcium needs for the day. But it would be only about 23% of a teen's calcium needs. That means that you can only really use the % DV as a guide to how much calcium your kids are getting from the foods they are eating each day.

Calcium Rich Foods

In addition to choosing foods from the following list, you should learn to look at food labels and choose foods that have a high % DV for calcium and at least 20% or more. You may find big differences in the calcium content of foods, even among different brands of the same foods such as cheese, juice, and bread.

• Yogurt, plain
• Yogurt, fruit
• Milk, low fat or nonfat
• Milk, whole
• Cheese, including American, ricotta, cheddar cheese and mozzarella cheese
• Milk shakes
• Eggn

Remember that just because your child is eating cheese, that doesn't mean that she is getting a lot of calcium. Check the nutrition label to make sure the cheese has a lot of calcium. And also look for foods made with these calcium rich foods as ingredients, such as a macaroni and cheese (cheese), pudding (milk), and nachos (cheese).

Nondairy Foods with Calcium

Getting enough calcium can be a especially hard if your kids are allergic to milk. These nondairy foods can be good choices for kids with milk allergies who need calcium:

• Salmon
• Tofu
• Rhubarb
• Sardines
• Collard greens
• Spinach
• Turnip greens
• Okra
• White beans
• Baked beans
• Broccoli
• Peas
• Brussel sprouts
• Sesame seeds
• Bok choy
• Almonds

Calcium-fortified Foods

In addition to the large number of calcium rich foods that are naturally found, like milk and cheese, a lot of foods are now fortified with calcium. These can be especially good choices if your child doesn't like to drink milk.

• Calcium-fortified breakfast cereal, including General Mills Whole Grain Total, Total Raisin Bran, Total Cranberry Crunch, and Total Honey Clusters, all of which have 100% DV of calcium per serving!
• Calcium-fortified orange juice
• Calcium-fortified soy milk
• SunnyD with Calcium (most SunnyD products don't have calcium, so look for the one that does if your child needs extra calcium in his diet)
• Instant oatmeal
• Calcium-fortified bread or English muffins
• Calcium-fortified drink mixes such as Pediasure or Carnation Instant Breakfast
• Other calcium-fortified breakfast cereals, including General Mills Golden Grahams (350 mg)

What You Need To Know

• Talk to your Pediatrician if you aren't sure if your child is getting enough calcium in his diet.

• Most varieties of children's vitamins don't have much calcium in them and you may need a special calcium supplement instead. 

• Choose from a combination of calcium rich foods to get even more calcium in your child's diet, such as a grilled cheese sandwich using calcium-fortified bread and cheese or a calcium fortified breakfast cereal with half a cup of low-fat milk.

• In addition to getting enough calcium in your diet, regular exercise is also important for healthy bones.

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Human Body - Muscular System

Muscular System

Muscular System : Introduction

The muscular system is the body's network of tissues that controls movement both of the body and within it (such as the heart's pumping action and the movement of food through the gut). Movement is generated through the contraction and relaxation of specific muscles.

The muscles of the body are divided into two main classes: skeletal (voluntary) and smooth (involuntary),

Skeletal muscles are attached to the skeleton and move various parts of the body. They are called voluntary because a person controls their use, such as in the flexing of an arm or the raising of a foot.

There are about 650 skeletal muscles in the whole human body. Smooth muscles are found in the stomach and intestinal walls, vein and artery walls, and in various internal organs. They are called involuntary muscles because a person generally cannot consciously control them. They are regulated by the autonomic nervous system (part of the nervous system that affects internal organs).

There are some others muscles which plays very important role in our body Cardiac Muscle (The heart is made up of the cardiac muscle), Facial Muscles (There are more than 30 muscles in the face) and Tongue (another unique muscle is the tongue, which is free at one end and only attached on the other end).

Another difference between skeletal and smooth muscles is that skeletal muscles are made of tissue fibers that are striated or striped. These alternating bands of light and dark result from the pattern of the filaments (threads) within each muscle cell. Smooth muscle fibers are not striated.

Human Muscle

The cardiac or heart muscle (also called myocardium) is a unique type of muscle that does not fit clearly into either of the two classes of muscle. Like skeletal muscles, cardiac muscles are striated. But like smooth muscles, they are involuntary, controlled by the autonomic nervous system.

The longest muscle in the human body is the sartorius (pronounced sar-TOR-ee-us). It runs from the waist down across the front of thigh to the knee. Its purpose is to flex the hip and knee. The largest muscle in the body is the gluteus maximus (pronounced GLUE-tee-us MAX-si-mus; buttocks muscles). It moves the thighbone away from the body and straightens out the hip joint.

Upon stimulation by an action potential, skeletal muscles perform a coordinated contraction by shortening each sarcomere. The best proposed model for understanding contraction is the sliding filament model of muscle contraction. Actin and myosin fibers overlap in a contractile motion towards each other. Myosin filaments have club-shaped heads that project toward the actin filaments.

Control : Muscular System

Neuromuscular junctions are the focal point where a motor neuron attaches to a muscle. Acetylcholine, (a neurotransmitter used in skeletal muscle contraction) is released from the axon terminal of the nerve cell when an action potential reaches the microscopic junction, called a synapse.

Muscle Control

A group of chemical messengers cross the synapse and stimulate the formation of electrical changes, which are produced in the muscle cell when the acetylcholine binds to receptors on its surface. Calcium is released from its storage area in the cell's sarcoplasmic reticulum.

An impulse from a nerve cell causes calcium release and brings about a single, short muscle contraction called a muscle twitch. If there is a problem at the neuromuscular junction, a very prolonged contraction may occur, tetanus. Also, a loss of function at the junction can produce paralysis.

Skeletal muscles are organized into hundreds of motor units, each of which involves a motor neuron, attached by a series of thin finger-like structures called axon terminals. These attach to and control discrete bundles of muscle fibers. A coordinated and fine tuned response to a specific circumstance will involve controlling the precise number of motor units used.

While individual muscle units contract as a unit, the entire muscle can contract on a predetermined basis due to the structure of the motor unit. Motor unit coordination, balance, and control frequently come under the direction of the cerebellum of the brain. This allows for complex muscular coordination with little conscious effort, such as when one drives a car without thinking about the process.

• Skeletal muscles : Muscular System

Skeletal

Skeletal muscles are probably the most familiar type of muscle. They are the muscles that ache after strenuous work or exercise. Skeletal muscles make up about 40 percent of the body's mass or weight. They stabilize joints, help maintain posture, and give the body its general shape. They also use a great deal of oxygen and nutrients from the blood supply.

Skeletal muscles are attached to bones by tough, fibrous connective tissue called tendons. Tendons are rich in the protein collagen, which is arranged in a wavy way so that it can stretch and provide additional length at the muscle-bone junction.

Skeletal muscles act in pairs. The flexing (contracting) of one muscle is balanced by a lengthening (relaxation) of its paired muscle or a group of muscles. These antagonistic (opposite) muscles can open and close joints such as the elbow or knee. An example of antagonistic muscles are the biceps (muscles in the front of the upper arm) and the triceps (muscles in the back of the upper arm). When the biceps muscle flexes, the forearm bends in at the elbow toward the biceps; at the same time, the triceps muscle lengthens. When the forearm is bent back out in a straight-arm position, the biceps lengthens and the triceps flexes.

Muscles that contract and cause a joint to close, such as the biceps, are called flexor muscles. Those that contract and cause a joint to open, such as the triceps, are called extensors. Skeletal muscles that support the skull, backbone, and rib cage are called axial skeletal muscles. Skeletal muscles of the limbs (arms and legs) are called distal skeletal muscles.

Skeletal muscle fibers are stimulated to contract by electrical impulses from the nervous system. Nerves extend outward from the spinal cord to connect to muscle cells. The area where a muscle and a nerve connect is called the myoneural juncture. When instructed to do so, the nerve releases a chemical called a neurotransmitter that crosses the microscopic space between the nerve and the muscle and causes the muscle to contract.

Skeletal muscle fibers are characterized as fast or slow based on their activity patterns. Fast (also called white) muscle fibers contract

rapidly, have poor blood supply, operate without oxygen, and tire quickly. Slow (also called red) muscle fibers contract more slowly, have better blood supplies, operate with oxygen, and do not tire as easily. Slow muscle fibers are used in movements that are ongoing, such as maintaining posture.

Human Body

• Smooth muscles : Muscular System

Smooth muscles are controlled directly by the autonomic nervous system and are involuntary, meaning that they are incapable of being moved by conscious thought. Functions such as heart beat and lungs (which are capable of being willingly controlled, be it to a limited extent) are involuntary muscles but are not smooth muscles.

Smooth muscle fibers line most of the internal hollow organs of the body, such as the intestines, stomach, and uterus (womb). They help move substances through tubular areas such as blood vessels and the small intestines. Smooth muscles contract automatically, spontaneously, and often rhythmically. They are slower to contract than skeletal muscles, but they can remain contracted longer.

Like skeletal muscles, smooth muscles contract in response to neurotransmitters released by nerves. Unlike skeletal muscles, some smooth muscles contract after being stimulated by hormones (chemicals secreted by glands). An example is oxytocin, a hormone released by the pituitary gland. It stimulates the smooth muscles of the uterus to contract during childbirth.

Smooth muscles are not as dependent on oxygen as skeletal muscles are. Smooth muscles use carbohydrates to generate much of their energy.

• Cardiac muscle : Muscular System

The heart is made up of the cardiac muscle, which is also referred to as the myocardium. These muscles are thick and contract in order to pump out the blood and then relax in order to allow more blood in. The cardiac muscle is an involuntary muscle, or the type that works without your volition. Special type of cells in the cardiac muscle, called the pacemaker, help in controlling the heartbeat.

Cardiac

The cardiac muscle or myocardium contracts (beats) more than 2.5 billion times in an average lifetime. Like skeletal muscles, myocardium is striated. However, myocardial muscle fibers are smaller and shorter than skeletal muscle fibers.

The contractions of the myocardium are stimulated by an impulse sent out from a small clump (node) of specialized tissue in the upper right area of the heart. The impulse spreads across the upper area of the heart, causing this region to contract. This impulse also reaches another node, located near the lower right area of the heart. After receiving the initial impulse, the second node fires off its own impulse, causing the lower region of the heart to contract slightly after the upper region.

• Facial Muscles : Muscular System

There are more than 30 muscles in the face. Not all of the facial muscles are attached to bones, as is the case in the other parts of the body.

Facial Muscles

Many of the facial muscles are attached to the underside of facial skin. The contractions of these muscles are what give the face its various expressions, such as frowning, laughter, surprise, sadness and so on.

• Tongue : Muscular System

Tongue is the unique muscles of musclar system, which is free at one end and only attached on the other end. The tongue actually comprises of a group of muscles, which work in unison, enabling you to chew and swallow food, and talk.

Tongue

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Human Body - Skeletal System

Human Skeletal

Skeletal System : Introduction 

Inside every person is a skeleton, a sturdy framework of 206 bones. The skeleton protects the body's organs, supports the body, and provides attachment points for muscles to enable body movement. The human skeleton consists of both fused and individual bones supported and supplemented by ligaments, tendons, muscles and cartilage. It serves as a scaffold which supports organs, anchors muscles, and protects organs such as the brain, lungs and heart. Bones also produce blood cells and act as a storage site for minerals such as calcium and phosphorus.

All humans are born with over 300 bones. But some bones, such as those in the skull and lower spine, fuse (join together) during growth, thereby reducing the number. The skeletal system is made up of living material, with networks of blood vessels running throughout. Living mature bone is about 60 percent calcium compounds and about 40 percent collagen (a fibrous protein). Hence, bone is strong, hard, and slightly elastic. Although mature bones consist largely of calcium, most bones in the human skeleton began as cartilage. Cartilage is a type of connective tissue that contains collagen and elastin fibers.

The biggest bone in the body is the femur in the thigh and the smallest is the stapes bone in the middle ear. In an adult, the skeleton comprises around 30-40% of the total body weight, and half of this weight is water.

Skeletal System

Fused bones include those of the pelvis and the cranium. Not all bones are interconnected directly: there are three bones in each middle ear called the ossicles that articulate only with each other. The hyoid bone, which is located in the neck and serves as the point of attachment for the tongue, does not articulate with any other bones in the body, being supported by muscles and ligaments.

Individual bones meet at areas called joints and are held in place by connective tissue. Cartilage lines the surface of many joints and helps reduce friction between bones. The connective tissues linking the skeleton together at the joints are ligaments and tendons. Both are made up of collagen, but serve different functions. Ligaments link bones together and help prevent dislocated joints. Tendons link bone to muscle. Because the bones making up the human skeleton are inside the body, the skeleton is called an endoskeleton. Some animals, such as the crab, have an external skeleton called an exoskeleton.

Structure : Skeletal System

The human skeletal system is divided into two main groups: the axial skeleton and the appendicular skeleton. The axial skeleton includes bones associated with the body's main axis, the spine. This includes the spine, the skull, and the rib cage. The appendicular skeleton is attached to the axial skeleton and consists of the bones associated with the body's appendages—the arms and legs. This includes the bones of the pectoral girdle (shoulder area), the pelvic girdle (hip area), and the arms and legs.

• Axial skeleton

There are 28 bones in the skull. In adults, the bones of the cranium (part of the skull that encloses the brain) are flat and interlocking at their joints. In infants, cartilage fills the spaces between the cranial bones. Known as soft spots or fontanelles, these spaces allow the skull bones to move slightly during birth. This makes birth easier and helps prevent skull fractures. Eventually, the fontanelles are replaced by bone. In addition to protecting the brain, skull bones also support and protect the organs responsible for sight, hearing, smell, and taste.

Skeletal Muscles

The skull rests atop the spine, which encases and protects the spinal cord. The spine, also called the spinal column or backbone, consists of 33 stacked vertebrae, the lower ones fused. The spinal column helps to support the weight of the body and protects the spinal cord. Disks of cartilage lie between the bony vertebrae of the back and provide cushioning, like shock absorbers. The vertebrae of the spine are capable of only limited movement, such as bending and some twisting.

Twelve pair of ribs (a total of 24) extend forward from the vertebrae of the upper back. Most of the ribs (the first seven pair) attach in the front of the body via cartilage to the long, flat breastbone, or sternum. These ribs are called true ribs. The next three pair of ribs, called false ribs, do not attach to the sternum. They are connected by cartilage to the ribs above them. The lower two pair of ribs that do not attach in the front are called floating ribs. Ribs give shape to the chest and support and protect the body's major organs, such as the heart and lungs. The rib cage also provides attachment points for connective tissue, to help hold organs in place.

• Appendicular skeleton. 

The appendicular skeleton joins with the axial skeleton at the shoulders and hips. Forming a loose attachment with the sternum is the pectoral girdle, or shoulder. Two bones, the clavicle (collar bone) and scapula (shoulder blade) form one shoulder. The major advantage to the loose attachment of the pectoral girdle is that it allows for a wide range of shoulder motions and greater overall freedom of movement.

Unlike the pectoral girdle, the pelvic girdle, or hips, is strong and dense. Each hip, left and right, consists of three fused bones—the ilium, ischium, and pubic. The pelvic girdle is bowl-shaped, with an opening at the bottom. In a pregnant woman, this bony opening is a passageway through which her baby must pass during birth. The pelvic girdle of women is generally wider than that of men, which helps to ease birth. The pelvic girdle protects the lower abdominal organs, such as the intestines, and helps supports the weight of the body above it.

Ligament

The arms and legs, appendages of the body, are very similar in form. The upper arm bone, the humerus, is the long bone between the elbow and the shoulder. It connects the arm to the pectoral girdle. In the leg, the thigh bone, or femur, is the long bone between the knee and hip that connects the leg to the pelvic girdle. The humerus and femur are sturdy bones, especially the femur, which is the longest bone in the body.

At the elbow the humerus attaches to a set of parallel bones—the ulna and radius—the bones of the forearm. These bones attach to the eight small carpal bones of the wrist. The hand is made up of 19 bones.

Similarly, in the leg, the femur attaches to a set of bones of the lower leg, the fibula and tibia. The tibia, or shin bone, is larger than the fibula and forms the joint behind the patella (kneecap) with the femur. At the ankle joint, the fibula and tibia connect to the seven tarsal bones forming the ankle and heel. These, in turn, are connected to the 19 bones that make up the foot.

Functions of the Skeletal System

• Support : 

The skeletal system is made up of bones and cartilages. There are 206 bones in the body and these bones and cartilages help provide the support and points of attachment to many soft tissues, muscles and ligaments in the body. There are different types of bones like the long bones, short bones, flat bones, irregular bones and sesamoid bones. The skeletal system functions also include providing rigidity and body shape. It helps supporting the weight of muscles and internal organs, without which the body would collapse.

Tendon

• Protection :

The skeleton protects many vital organs:

• The skull protects the brain, the eyes, and the middle and inner ears.
• The vertebrae protects the spinal cord.
• The rib cage, spine, and sternum protect the lungs, heart and major blood vessels.
• The clavicle and scapula protect the shoulder.
• The ilium and spine protect the digestive and urogenital systems and the hip.
• The patella and the ulna protect the knee and the elbow respectively.
• The carpals and tarsals protect the wrist and ankle respectively.

• Helping in Movement :

The bone joint act as levers and anchors for the muscles. The point of origin of the muscle is called the anchor and the bone acts as lever. There are three types of joints, viz. fixed joint or Synarthroses like the skull bones, the slightly movable or Amphiarthroses like the symphysis pubis and the freely movable or Diarthroses. The freely movable joints are divided into four groups. The first, ball and socket joint like the hip joint, the hinge joint in the anatomy of elbow, the pivot joint of the radius and ulna and the gliding joint are seen in the carpal joint of wrist.

• Storage of Minerals :

Bone matrix can store calcium and is involved in calcium metabolism, and bone marrow can store iron in ferritin and is involved in iron metabolism. However, bones are not entirely made of calcium,but a mixture of chondroitin sulfate and hydroxyapatite, the latter making up 70% of a bone.

• Production of Red Blood Cells :

The red blood cells as well as the white blood cells are produced in the red marrow of the bones. After birth and in early childhood, the red blood morrow is red in color. Then, in adulthood, half of the bone marrow turns yellow, as it consists of fat cells. The long bones consist of yellow marrow and the red marrow is found in the flat bones of hip, skull and shoulder blades. You may also find red marrow in the vertebrae and the end of the long bone. In extreme conditions, the body can convert some of the yellow bone marrow to red bone marrow.

• Chemical Energy Storage :

Bone cells release a hormone called osteocalcin, which contributes to the regulation of blood sugar (glucose) and fat deposition. Osteocalcin increases both the insulin secretion and sensitivity, in addition to boosting the number of insulin-producing cells and reducing stores of fat.

Human Body Muscles and Human Anatomy

Interesting Facts About Skeletal System

• There are 206 bones in an adult human body.
• A baby is born with 300 bones. But throughout the growth years, many of the bones of the skull and spine fuse together.
• Bones do not move on their own, they need the help of the muscles attached to the bones.
• Bones have life. They’re made up of living cells that is why they can grow and repair themselves.
• The longest bone, about one-quarter of a person’s overall height, is the femur bone. It’s located in the leg.
• The smallest bone in the body is the stirrup bone, located deep inside the ear. It is just a little larger than a grain of rice.
• The largest bone in the body is the pelvic bone.
• Collar bone is the most frequently broken bone in a human body. It is also known as clavicle.
• Hyoid bone is the only bone that is not connected to any other bone. It is located in the throat of a human’s body.
• Most bones consist of two types of bone tissues, namely compact hard bones and spongy bone.
• More than half of the bones in the body are located in the hands and feet together.
• Humans and giraffes have the same number of bones in their necks. It is just that giraffes have a much longer vertebra.
• Bones are filled with a substance called bone marrow that is critical for the production of red and white blood cells.
• There are two types of bone marrow. Red marrow produces blood cells while yellow marrow produces fatty cells.
• At birth, all bone marrow is red.
• The ears and the end of the nose don't have bones. These parts of the body are given their shape by cartilage.
• Cartilage is lighter and flexible than bone, allowing movement and the ability to bend.
• Cartilage degrades faster than bone that is why many human remains are found without a nose or ears.
• Cartilage contains no blood vessels or nerve cells.
• Embryos contain cartilage, not bones.
• In adults, the skeleton makes up for 15-20 percent of total body weight.

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