Health Articles

Skeletal System

The Skeletal System

Muscular System

In muscular system there are three different groups
These are three different groups.:
1. SMOOTH MUSCLES - The smooth muscles are muscles that we don't have control of. They include muscles that surround organs including the stomach, lungs, and intestines. Because we cannot control them, they are called "involuntary muscles"

2. SKELETAL MUSCLES - Skeletal muscles are muscles that are directly attached to bones. These muscles are responsible for all of the movement our body can accomplish. When most people think of muscles, they think of skeletal muscles.

3. CARDIAC MUSCLES - Cardiac muscles are only found in one place in your body...your heart. This involuntary set of muscles make up the chambers of your heart. They pump all day and night transporting blood throughout the body.
Muscles are only able to CONTRACT or pull. Because our body has to move in many directions, most muscles are set up in pairs so that one muscle can pull a bone in one direction, and another muscle can pull the bone back the other way.

There are over 600 kinds of muscles that scientists have named. Some muscles are tiny - when we get goosebumps, we are actually seeing a tiny muscle contracting to raise a hair. The longest muscle is satorius muscle in your leg. The largest muscle in the body is Gluteus Maximus - the muscle you sit on!
The Human Muscular System Back
1. Occipitalis
2. Semispinalis Capitis
3. Splenius Capitis
4. Sternocleidomastoid
5. Trapezius
6. Deltiod
7. Teres Minor
8. Teres Major
9. Triceps Brachii
10. Latissimus Dorsi
11. Brachioradialis
12. Extensor Carpi Radialis Longus
13. Anconeus
14. Extensor Carpi Radialis Brevis
15. Extensor Digitorum
16. Flexor Carpi Ulnaris
17 Extensor Carpi Ulnaris
18. Erector Spinae
19. Internal & External Oblique
20. Gluteus Medius & Gluteus Minimus (underneath Gluteus Medius)
21. Gluteus Maximus
22. Vastus Lateralis
23. Gracilis
24. Adductor Magnus
25. Biceps Femoris
26. Semitendinosus
27. Semimembranosus
28. Gastocnemius
29. Soleus
30. Peroneus Longus
31. Flexor Digitorum Longus
32. Extensor Digitorum Longus

The Human Muscular System Front

1. Galea Aponeurotica
2. Epicranius
3. Orbicularis Oculi
4. Nasalis
5. Levator Labii Superioris
6. Zygomaticus major & minor
7. Orbicularis Oris
8. Risorius
9. Depressor Anguli Oris
10. Depressor Labii Inferioris
11. Mentalis
12. Omohyoid
13. Sternohyoid
14. Sternal Head of Sternocleidomastoid
15. Scalene
16. Trapezius
17. Deltoid
18. Pectoralis Major
19. Serratus Anterior
20. Rectus Abdominis
21. External Abdominal Oblique
22. Biceps Brachii
23. Brachialis
24. Pronator Teres
25. Brachioradialis
26. Flexor Carpi Radialis
27. Extensor Carpi Radialis
28. Tensor Fasciae Latae
29. Iliopsoas
30. Pectineus
31. Sartorius
32. Adductor Longus
33. Gracilis
34. Rectus Femoris
35. Vastus Intermedius
36. Vastus Lateralis
37. Vastus Medialis
38. Gastrocnemius
39. Peroneus Longus
40. Tibialis Anterior
41. Soleus
42. Peroneus Brevis
43. Extensor Digitorum Longus

Nervous System

As the most complex system, the nervous system serves as the body control center and communications electrical-chemical wiring network. As a key homeostatic regulatory and coordinating system, it detects, interprets, and responds to changes in internal and external conditions. The nervous system integrates countless bits of information and generates appropriate reactions by sending electrochemical impulses through nerves to effector organs such as muscles and glands. The brain and spinal cord are the central nervous system (CNS); the connecting nerve processes to effectors and receptors serve as the peripheral nervous system (PNS). Special sense receptors provide for taste, smell, sight, hearing, and balance. Nerves carry all messages exchanged between the CNS and the rest of the body.
Human Nervous System

Nervous system: set of nerves, ganglions and nervous centers that receive sensory signal. Commands and coordinates vital functions.
Brachial plexus: network of nerves of the arm.
Intercostal nerve: cord conducting nerve impulses between the ribs.
Radial nerve: cord conducting nerve impulses in the area of the radius.
Median nerve: main cord conducting nerve impulses in the upper limb.
Ulnar nerve: cord conducting nerve impulses in the area of the elbow.
Lumbar plexus: network of nerves of the lower back.
Sciatic nerve: cord conducting nerve impulses in the area of the thigh and lower leg.
Common peroneal nerve: cord conducting nerve impulses along the inside of the lower leg.
Superficial peroneal nerve: cord conducting nerve impulses of the muscles and skin of the leg.
Digital nerve: cord conducting nerve impulses of the fingers.
Sacral plexus: network of nerves of the sacrum.
Spinal cord: substance belonging to the nervous system, found in the holes of the vertebrae.
Cerebellum: nervous centre situated under the brain.
Cerebrum: seat of the mental capacities.

Endocrine System

Human Endocrine System

About the Endocrine System




prolactin, which activates milk production in women who are breastfeeding
thyrotropin, which stimulates the thyroid gland to produce thyroid hormones
corticotropin, which stimulates the adrenal gland to produce certain hormones


The thyroid, located in the front part of the lower neck, is shaped like a bowtie or butterfly and produces the thyroid hormones thyroxine and triiodothyronine. These hormones control the rate at which cells burn fuels from food to produce energy. As the level of thyroid hormones increases in the bloodstream, so does the speed at which chemical reactions occur in the body.



What the Endocrine System Does


Problems With the Endocrine System

Type 1 diabetes. When the pancreas fails to produce enough insulin, type 1 diabetes (previously known as juvenile diabetes) occurs. Symptoms include excessive thirst, hunger, urination, and weight loss. In children and teens, the condition is usually an autoimmune disorder in which specific immune system cells and antibodies produced by the immune system attack and destroy the cells of the pancreas that produce insulin. The disease can cause long-term complications including kidney problems, nerve damage, blindness, and early coronary heart disease and stroke. To control their blood sugar levels and reduce the risk of developing diabetes complications, kids with this condition need regular injections of insulin.

Type 2 diabetes. Unlike type 1 diabetes, in which the body can't produce normal amounts of insulin, in type 2 diabetes the body is unable to respond to insulin normally. Children and teens with the condition tend to be overweight, and it is believed that excess body fat plays a role in the insulin resistance that characterizes the disease. In fact, the rising prevalence of this type of diabetes in kids has paralleled the dramatically increasing rates of obesity among kids in recent years. The symptoms and possible complications of type 2 diabetes are basically the same as those of type 1. Some kids and teens can control their blood sugar level with dietary changes, exercise, and oral medications, but many will need to take insulin injections like patients with type 1 diabetes.




Puberty, usually occurring during adolescence, is when kids develop physically and emotionally into young men and women. Usually, this starts to happen no earlier than about 7 to 8 years of age for girls and 9 years of age for boys (the average age is about 10 for girls and 12 for boys). But what if a younger child - for example, a 5-year-old girl - begins showing the signs of puberty? How would it affect her?
Precocious puberty - the onset of signs of puberty before age 7 or 8 in girls and age 9 in boys - can be physically and emotionally difficult for children and can sometimes be the sign of an underlying health problem.

Precocious Puberty

What are the Signs of Precocious Puberty?
• breast development
• pubic or underarm hair development
• rapid height growth - a growth "spurt"
• onset of menstruation
• acne
• "mature" body odor
• enlargement of the testicles or penis
• pubic, underarm, or facial hair development
• rapid height growth - a growth "spurt"
• voice deepening
• acne
• "mature" body odor

Many children who show some of the early signs of puberty have what's known as "partial" precocious puberty. Some girls, usually beginning between the ages of 6 months and 3 years, may show breast development that later disappears or may persist without other physical changes of puberty.

Similarly, some girls and boys may experience early growth of pubic and/or underarm hair that isn't associated with other changes in sexual development. Children with "partial" precocious puberty may require evaluation to rule out "true" precocious puberty or other health problems, but they generally need no treatment and usually will show the other expected signs of puberty at the usual age.

How Does Precocious Puberty Affect a Child?

What Causes Precocious Puberty?
For the majority of girls, there's no underlying medical problem - they simply start puberty too early for no known reason. In boys, the condition is less common, and more likely to be associated with an underlying medical problem than it is in girls.
In about 5% of boys, precocious puberty is inherited. Starting puberty early can be passed to the son from the father or to the son from the maternal grandfather through the mother (who will not be affected by the disorder). But less than 1% of girls affected by precocious puberty have inherited the condition.

How Is Precocious Puberty Diagnosed?
Talk to your child's doctor if your child shows any signs of early sexual maturation before age 7 or 8 in girls or age 9 in boys, including breast development, rapid height growth, menstruation, acne, enlarged testicles or penis, or pubic or underarm hair.
The physical changes boys and girls go through during puberty are usually evident to a doctor during an exam. To confirm a diagnosis of precocious puberty, your child's doctor may order blood and urine tests to detect elevated levels of sex hormones. And X-rays of your child's wrist and hand can show whether the bones are maturing too rapidly.

How Is Precocious Puberty Treated?
If your child's doctor suspects that your little one has precocious puberty, he or she may refer you to a pediatric endocrinologist (a doctor who specializes in growth and hormonal disorders in children) for further evaluation and treatment.
Once it's diagnosed, the goal of treating precocious puberty is to halt or even reverse sexual development and stop the rapid growth and bone maturation that can eventually result in adult short stature. Depending upon the cause, there are two possible approaches to treatment:
2. lowering the high levels of sex hormones with medication to stop sexual development from progressing
In some cases, treatment of an underlying health problem can stop the precocious puberty from progressing. But in most cases, because there's no other disease triggering the condition, treatment usually consists of hormone therapy that stops sexual development.
The currently approved hormone treatment is with drugs called LHRH analogs - synthetic hormones that block the body's production of the sex hormones that are causing the early puberty. Dramatic results are usually seen within a year of starting treatment with an LHRH analog, which is generally safe and usually causes no side effects in children. In girls, breast size may decrease - or at least there will be no further development. In boys, the penis and testicles may shrink back to the size expected for their age. Growth in height will also slow down to a rate expected for children before puberty. A child's behavior usually becomes more age appropriate as well.

Caring for Your Child
Give your child a simple, truthful explanation about what's happening. Explain that these changes are normal for older kids and teens, but that his or her body has started developing a little too early. Keep your child informed about his or her treatment and what can be expected along the way.
• poor grades
• problems at school
• loss of interest in daily activities
• depression
How you cope with the issue can also determine how successfully your child will cope. The goal is to prevent your child from dwelling on sexual development or developing a poor self-image or low self-esteem. To create a supportive environment, try not to focus your comments on your child's appearance; instead, offer praise for achievements in school or sports and support your child's participation in other activities.
The important thing to remember is that children with precocious puberty can be treated. Doctors can help your child preserve his or her adult height potential as well as limit the emotional and social difficulties your child may face from maturing early.

About Puberty

What is Puberty?
Puberty is the time when your body starts to change from that of a child to that of an adult. Going from childhood to adulthood is not just a bodily process many other changes will accompany it.
Many changes occur during this time and hormones bring on these changes. Hormones are chemicals released by the brain, as the brain knows when the body is reaching sexual, physical and intellectual maturity. Different types of hormones are responsible for different changes occurring in you. The hormones that bring on the onset of puberty come from a gland near the brain called the pituitary gland. There are hormones that promote the production of other hormones called estrogen and progesterone in girls’ ovaries and in boys the hormonetestoterone is produced in the testicles.
About Puberty for Both Girl&Boy
During this period growth of hormones become active as well, these are responsible for the physical changes that occur in your body. Your body will grow taller you will gain weight
and your shape will change in a general way as well. It is important to know that not everybody experiences these changes at the same time; some people's ‘growth spurt’ might come earlier or later than others and might vary in degrees.
Other types of hormones that affect you during this period are those responsible for the emotional changes. These could generate feelings of confusion, sadness, mood swings and possibly a quick temper. You may experience varying positive or negative feelings and these too are provoked by hormonal changes. You might also feel more self-conscious and possibly socially isolated. It is important to understand that this is normal. These feelings may vary in severity between different people. The best way to deal with this is to talk to someone you trust, choose a family member you can communicate with. Your mother, your aunt, your father or an older sibling could be the best person to talk to, remember that your family is there to support you in all your needs. Communicating with people who care for you is very important, it can help clear much of the confusion you are feeling and can help you look at things from a different perspective.

Emotional changes:
Puberty is not just about physical changes; emotional changes are a big part of this period and these two go together. You might be feeling more self-conscious about the physical changes you are going through. It is important to try not to compare your development with others your age as every person is a unique individual with special needs and problems and his/her development is specific to him/her.

As you are moving from being a young girl or young boy to becoming a woman or a man, your thinking is changing as well. Your relationships, interests, priorities and your world and the important people in it will change as well. This may sound easy but it is not always so. It is important to realize that you are not alone in this and it is not impossible for caring adults in your family to understand what you are going through.
Those crazy hormones are acting up again and they bring on these emotional changes again. Following are some of the emotional changes you might experience during this time:
- You may feel confused.
- You may develop very strong emotions.
- You may feel sad.
- You might have frequent mood changes.
- You might be over sensitive.
- You might get angry and lose your temper more easily.
- You might experience a sense of not belonging to your family, friends etc.
- You might experience problems at school.
- You may ask yourself is it normal to feel what you are feeling.
Yes it is normal to feel this way, you might experience some or most of these emotional symptoms. When matters become too hard to deal with on your own, you have to remember that there are many people who love and care for you no matter what you are going through. Try to approach a person in your family you trust and feel comfortable enough to address these issues with. You will notice how much better you will feel when you share the burden of these emotions with someone you trust. Remember that all adults have gone through this before even your parents.

When does puberty happen?
Puberty is a process that does not follow a strict timeline and it affects each person according to his or her own internal calendar; although it generally starts earlier for girls than boys.
Puberty for girls can begin between ages nine and fourteen, for boys it will be between the ages of ten and seventeen. These age brackets are considered as the norm though anything happening slightly before or after this could still be considered normal. This development process can last from one year to as many as six years. For some it might be a rather quick process or an early one for some it might happen later and take longer.
In the following section we will talk about the physical changes that happen during puberty.

Cardiovascular System

The cardiovascular system is sometimes called the blood-vascular or simply the circulatory system. It consists of the heart, which is a muscular pumping device, and a closed system of vessels called arteries, veins, and capillaries. As the name implies, blood contained in the circulatory system is pumped by the heart around a closed circle or circuit of vessels as it passes again and again through the various "circulations" of the body.

Human Cardiovascular System

As in the adult, survival of the developing embryo depends on the circulation of blood to maintain homeostasis and a favorable cellular environment. In response to this need, the cardiovascular system makes its appearance early in development and reaches a functional state long before any other major organ system. Incredible as it seems, the primitive heart begins to beat regularly early in the fourth week following fertilization.


Numerous control mechanisms help to regulate and integrate the diverse functions and component parts of the cardiovascular system in order to supply blood to specific body areas according to need. These mechanisms ensure a constant internal environment surrounding each body cell regardless of differing demands for nutrients or production of waste products.

Lymphatic system

The lymphatic system is a network of tubes throughout the body that drains fluid (called lymph) from tissues and empties it back into the bloodstream. The main roles of the lymphatic system include managing the fluid levels in the body, filtering out bacteria, and housing types of white blood cells. Lymph is filtered through the spleen, thymus and lymph nodes before being emptied into the blood.

Human Lymphatic System

Keeping a balance of fluid
Blood vessels tend to seep fluid into surrounding tissue. The lymphatic system drains off any extra fluid to stop the tissues from puffing up. The feet in particular are prone to puffiness.

Lymphatic vessels
Lymphatic vessels criss-cross the entire body, except for the central nervous system. Some lymphatic vessels have valves (similar to the valves in veins), which stop the lymph from running back the wrong way.

The spleen is inside the abdomen, just under the diaphragm. This is one of the filtering organs of the blood. As well as removing microbes, the spleen also destroys old or damaged red blood cells.

The thymus is inside the ribcage, just behind the breastbone. This is another filtering organ of the blood, that contains many white blood cells called lymphocytes.

Lymph nodes
Lymph nodes are found at various points around the body, including the throat, armpits, chest, abdomen and groin. All lie close to arteries. Bacteria picked up from the tissues by the lymph are trapped in the lymph node. White blood cells called lymphocytes can then attack and kill the bacteria. This is why your lymph nodes tend to swell if you have an infection. Viruses and cancer cells are also trapped by lymph nodes.

Common problems
Some common problems of the lymphatic system include:
• Glandular fever - symptoms include tender lymph nodes
• Hodgkin’s disease - a type of cancer of the lymphatic system
• Oedema - swelling caused by too much fluid in the tissues
• Tonsillitis - infection of the tonsils in the throat.

Things to remember
• The lymphatic system maintains fluid levels in the body.
• Bacteria and other microbes are taken up by the lymph and delivered to the lymph nodes for destruction.
• The spleen and thymus are organs that filter the blood.

Digestive System

The digestive system is made up of the digestive tract—a series of hollow organs joined in a long, twisting tube from the mouth to the anus—and other organs that help the body break down and absorb food (see figure).

Organs that make up the digestive tract are the mouth, esophagus, stomach, small intestine, large intestine—also called the colon—rectum, and anus. Inside these hollow organs is a lining called the mucosa. In the mouth, stomach, and small intestine, the mucosa contains tiny glands that produce juices to help digest food. The digestive tract also contains a layer of smooth muscle that helps break down food and move it along the tract.

Two “solid” digestive organs, the liver and the pancreas, produce digestive juices that reach the intestine through small tubes called ducts. The gallbladder stores the liver’s digestive juices until they are needed in the intestine. Parts of the nervous and circulatory systems also play major roles in the digestive system.
Human Digestive System
Why is digestion important?

How is food digested?

Movement of Food Through the System
The large, hollow organs of the digestive tract contain a layer of muscle that enables their walls to move. The movement of organ walls can propel food and liquid through the system and also can mix the contents within each organ. Food moves from one organ to the next through muscle action called peristalsis. Peristalsis looks like an ocean wave traveling through the muscle. The muscle of the organ contracts to create a narrowing and then propels the narrowed portion slowly down the length of the organ. These waves of narrowing push the food and fluid in front of them through each hollow organ.

The first major muscle movement occurs when food or liquid is swallowed. Although you are able to start swallowing by choice, once the swallow begins, it becomes involuntary and proceeds under the control of the nerves.

Swallowed food is pushed into the esophagus, which connects the throat above with the stomach below. At the junction of the esophagus and stomach, there is a ringlike muscle, called the lower esophageal sphincter, closing the passage between the two organs. As food approaches the closed sphincter, the sphincter relaxes and allows the food to pass through to the stomach.

The stomach has three mechanical tasks. First, it stores the swallowed food and liquid. To do this, the muscle of the upper part of the stomach relaxes to accept large volumes of swallowed material. The second job is to mix up the food, liquid, and digestive juice produced by the stomach. The lower part of the stomach mixes these materials by its muscle action. The third task of the stomach is to empty its contents slowly into the small intestine.

Several factors affect emptying of the stomach, including the kind of food and the degree of muscle action of the emptying stomach and the small intestine. Carbohydrates, for example, spend the least amount of time in the stomach, while protein stays in the stomach longer, and fats the longest. As the food dissolves into the juices from the pancreas, liver, and intestine, the contents of the intestine are mixed and pushed forward to allow further digestion.

Finally, the digested nutrients are absorbed through the intestinal walls and transported throughout the body. The waste products of this process include undigested parts of the food, known as fiber, and older cells that have been shed from the mucosa. These materials are pushed into the colon, where they remain until the feces are expelled by a bowel movement.

Production of Digestive Juices
The digestive glands that act first are in the mouth—the salivary glands. Saliva produced by these glands contains an enzyme that begins to digest the starch from food into smaller molecules. An enzyme is a substance that speeds up chemical reactions in the body.
The next set of digestive glands is in the stomach lining. They produce stomach acid and an enzyme that digests protein. A thick mucus layer coats the mucosa and helps keep the acidic digestive juice from dissolving the tissue of the stomach itself. In most people, the stomach mucosa is able to resist the juice, although food and other tissues of the body cannot.

After the stomach empties the food and juice mixture into the small intestine, the juices of two other digestive organs mix with the food. One of these organs, the pancreas, produces a juice that contains a wide array of enzymes to break down the carbohydrate, fat, and protein in food. Other enzymes that are active in the process come from glands in the wall of the intestine.

The second organ, the liver, produces yet another digestive juice—bile. Bile is stored between meals in the gallbladder. At mealtime, it is squeezed out of the gallbladder, through the bile ducts, and into the intestine to mix with the fat in food. The bile acids dissolve fat into the watery contents of the intestine, much like detergents that dissolve grease from a frying pan. After fat is dissolved, it is digested by enzymes from the pancreas and the lining of the intestine.

Absorption and Transport of Nutrients
Most digested molecules of food, as well as water and minerals, are absorbed through the small intestine. The mucosa of the small intestine contains many folds that are covered with tiny fingerlike projections called villi. In turn, the villi are covered with microscopic projections called microvilli. These structures create a vast surface area through which nutrients can be absorbed. Specialized cells allow absorbed materials to cross the mucosa into the blood, where they are carried off in the bloodstream to other parts of the body for storage or further chemical change. This part of the process varies with different types of nutrients.

Carbohydrates. The Dietary Guidelines for Americans 2005 recommend that 45 to 65 percent of total daily calories be from carbohydrates. Foods rich in carbohydrates include bread, potatoes, dried peas and beans, rice, pasta, fruits, and vegetables. Many of these foods contain both starch and fiber.

The digestible carbohydrates—starch and sugar—are broken into simpler molecules by enzymes in the saliva, in juice produced by the pancreas, and in the lining of the small intestine. Starch is digested in two steps. First, an enzyme in the saliva and pancreatic juice breaks the starch into molecules called maltose. Then an enzyme in the lining of the small intestine splits the maltose into glucose molecules that can be absorbed into the blood. Glucose is carried through the bloodstream to the liver, where it is stored or used to provide energy for the work of the body.

Sugars are digested in one step. An enzyme in the lining of the small intestine digests sucrose, also known as table sugar, into glucose and fructose, which are absorbed through the intestine into the blood. Milk contains another type of sugar, lactose, which is changed into absorbable molecules by another enzyme in the intestinal lining.

Fiber is undigestible and moves through the digestive tract without being broken down by enzymes. Many foods contain both soluble and insoluble fiber. Soluble fiber dissolves easily in water and takes on a soft, gel-like texture in the intestines. Insoluble fiber, on the other hand, passes essentially unchanged through the intestines.





How is the digestive process controlled?
Hormone Regulators
The main hormones that control digestion are gastrin, secretin, and cholecystokinin (CCK):
• Secretin causes the pancreas to send out a digestive juice that is rich in bicarbonate. The bicarbonate helps neutralize the acidic stomach contents as they enter the small intestine. Secretin also stimulates the stomach to produce pepsin, an enzyme that digests protein, and stimulates the liver to produce bile.
• CCK causes the pancreas to produce the enzymes of pancreatic juice, and causes the gallbladder to empty. It also promotes normal cell growth of the pancreas.

Additional hormones in the digestive system regulate appetite:
• Peptide YY is produced in the digestive tract in response to a meal in the system and inhibits appetite.

Both of these hormones work on the brain to help regulate the intake of food for energy. Researchers are studying other hormones that may play a part in inhibiting appetite, including glucagon-like peptide-1 (GPL-1), oxyntomodulin (+ ), and pancreatic polypeptide.

Nerve Regulators
Extrinsic, or outside, nerves come to the digestive organs from the brain or the spinal cord. They release two chemicals, acetylcholine and adrenaline. Acetylcholine causes the muscle layer of the digestive organs to squeeze with more force and increase the “push” of food and juice through the digestive tract. It also causes the stomach and pancreas to produce more digestive juice. Adrenaline has the opposite effect. It relaxes the muscle of the stomach and intestine and decreases the flow of blood to these organs, slowing or stopping digestion.

Together, nerves, hormones, the blood, and the organs of the digestive system conduct the complex tasks of digesting and absorbing nutrients from the foods and liquids you consume each day.

Urinary System

How does the urinary system work?

Human Urinary System








What causes problems in the urinary system?

How are problems in the urinary system detected?



What are some disorders of the urinary system?










Who can help me with a urinary problem?

Points to Remember