Respiratory System

What’s come up on your mind when you hear the word respiratory system? Respiratory System is the integrated system of organs involved in the intake and exchange of oxygen and carbon dioxide between an organisms and the environment.

The main function of respiratory system is to supply blood with oxygen in order for the blood to deliver oxygen to all parts of our body. The respiratory system does this through breathing. When we breathe, we inhale oxygen and we exhale carbon dioxide. This exchange of gases in the respiratory system means we getting oxygen to the blood.

Respiration is achieved by our mouth, nose, trachea, lungs, and diaphragm. Then, the oxygen passes through the larynx (speech sounds are produced here) and the trachea (a tube that enters the chest cavity). In the chest cavity, the trachea divides into 2 smaller tubes. It is called the bronchi. Then, each bronchus divides again form the bronchial tubes. The bronchial tubes lead directly into the lungs where they divides into many smaller tubes which connect to the tiny sacs called alveoli. The average adult’s lungs contain about 600 millions of these spongy, air-filled sacs that are surrounded by capillaries. The inhaled oxygen passes into the alveoli. Then, diffuses through the capillaries into the arterial blood. The waste-rich blood from the veins releases its carbon dioxide into the alveoli. The carbon dioxide then out of the lungs when you exhale.

The diaphragm’s job is to help pumping the carbon dioxide out of the lungs and pull the oxygen to the lungs. Diaphragm is a sheet of muscles that lies across the bottom of the chest cavity. As the diaphragm contracts and relaxes, breathing takes place. When the diaphragm contracts, oxygen is pulled in the lungs. While when the diaphragm relaxes, carbon dioxide is pumped out of the lungs.

The diseases of the lungs are pneumonia, asthma, chronic bronchitis, and lung cancer. Pneumonia is an infection of the alveoli. It caused because of many kind of both bacteria and viruses. In asthma, periodic constriction of the bronchi and bronchioles makes it more difficult to breathe in, and specially breathe out. Attacks of asthma can be triggered by airborne irritants such as chemical fumes and cigarette smoke; airborne particles to which the patient is allergic. In chronic bronchitis, the air passage becomes clogged with mucus, and this lead to a persistent cough. Chronic bronchitis is usually associated with cigarette smoking. Lung cancer is the most common cancer and the most common causes of cancer in world. Lung cancer is uncontrolled proliferation of cells. There are several forms of lung cancer, but the most common types are those involving the epithelial cells lining the bronchi and bronchioles. Ordinarily, the lining of these airways consists of two layers of cells. Chronic exposure to irritants causes the numbers of layers to increase. This is especially apt to happen at forks where bronchioles branch.

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By : Alyssa Chrysilla 9C

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Circulatory System

The circulatory system is an organ system that passes nutrients ,gases, hormones, blood cells, etc. to and from cells in the body to help fight diseases and help stabilize body temperature and maintain homeostasis. Circulatory system is also called cardiovascular system, which means it distributes blood.

The main components of the human cardiovascular system are the heart, the veins, and the blood vessels.It includes the pulmonary circulation,which is a loop through the lungs where blood is oxygenated.And the systemic circulation, a “loop” through the rest of the body to provide oxygenated blood.

The Pulmonary Circulation

The Pulmonary circulation is the portion of the cardiovascular system which transports oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart.

In this process, deoxygenated blood enters the interior or superior Vena Cava and enters the right atrium of the heart. Then it flows through the tricuspid valve and into the right ventricle. In the right ventricle it will be pumped to the pulmonary arteries and flow to the lungs.

In the lungs it converts the deoxygenated blood to oxygenated blood and then the new oxygenated blood will enter the pulmonary vein. Then it will flow to the left atrium and keeps flowing through mitral valve into the left ventricle. And then the blood will be pumped through the aorta and to the different parts of the body.

The Systemic Circulation

Unlike the Pulmonary Circulation which is the circulation of blood between the heart and the lung, the Systemic circulation is the portion of the cardiovascular system which transports oxygenated blood away from the heart, to the rest of the body, and returns oxygen-depleted blood back to the heart.

Distance-wise, the systemic circulation is longer than the pulmonary circulation. It starts from the aorta, to the different parts of the body, and back to the vena cava of the heart.

Circulatory System Diseases

The circulatory system also can get serious diseases. It can cause death because it involves the human’s most important important body parts, which are the heart and the lung.There are two diseases identified that is a circulatory system disease.

The first one is the heart disease or cardiovascular disease are the class of diseases that involve the heart or blood vessels (arteries and veins). While the term technically refers to any disease that affects the cardiovascular system , it is usually used to refer to those related to atherosclerosis (arterial disease). These conditions usually have similar causes, mechanisms, and treatments.Most countries face high and increasing rates of cardiovascular disease. Each year, heart disease kills more Americans than cancer.

The causes of the heart disease are smoking, alcohol consumption, high blood pressure, high cholesterol, over weight or obese, diabetes that aren’t managed properly, and stress.

The second one is congenital heart defect (CHD) which is a defect in the structure of the heart and great vessels which is present at birth. Many types of heart defects exist, most of which either obstruct blood flow in the heart or vessels near it, or cause blood to flow through the heart in an abnormal pattern.

By: Anindya Pradnya P 9C

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What comes into your mind when you hear that word? Probably such a hazardous thing or even crime. Well, everything is not what it seems. Do you know that apparently drugs possessed huge benefit in daily need as well frequently save many lives? Why it have to be in the exact dosage?. How it can be harmful at the same time?. To solve this, let’s take a look on the general clarification…..
Drugs is a chemical substance when taken into the body, have an effect on the body form or body function.
Specifically, drugs have a wide range of varieties and divide into three parts:
Medicinal drugs
For instance, Aspirin, paracetamol, antibiotics

Drugs of abuse
Heroine, coccaine

Acceptable drugs

Alcohol, nicotine,caffeine
As we examined each of the type clearly, it is obvious that medicinal drugs used for medical need and those example (aspirin, paracetamol,antibiotics) designed to surpress pain, counteract the symptomps of flu,soothe muscular pain or kill pathogenic bacteria. Acceptable drug consumed by people for pleasurable effect, help them relax or concentrate. Most people use drug in careful and wise manner. Drug abuse result when a person take drug excessively and without doctor prescription. Taking drugs that way can be extremely harmful to the body. It may even result in death.
Drugs which are generally abused can be classified into four major categories:
Depressant drugs
Stimulant drugs
Hallucinogenic drugs
Drug types Effects on Body Examples
Depressant drugs “depress” the central nervous system. Calm the body and help to put the user to sleep. Barbiturates and tranquilizers
Used as sleeping pills to overcome insomnia and treat epilepsy.
Stimulant drugs Stimulate central nervous system Amphetamine and cocaine used to counteract depression, prevent fatigue and counteract hunger. Increasingly, Ice and Ectasy are also used by teenager.
Hallucinogenic drugs Cause the user to experience hallucinations, illusion, distorted image and feeling ‘high’. Marijuana
Opiates Relieve pain, calm and numb the body and mind. They also create dreamlike feeling of happiness. Heroin . it cause euphoria which is the feeling of warm rush as well contentment.

Bad side??
One effect of drug is drug tolerance. The user has to take more and more of the drug in order to get the same effect or feeling. The most harmful effects of drug abuse is addiction to drugs. This means that user cannot do without the drug. Drug that cause addiction are usually those that excite or depress the nervous system, for instance heroin. the addict needs a continual supply of drug he/she is addicted to.
When a person who is dependent on a drug stops using it, he feels ill and suffers from strong withdrawal symptoms. Withdrawal symptomps for addicts include anxiety, upsets, sweating, vomitting, convulsion and hallucination. Withdrawal symptoms can be so severe that sudden withdrawal from certain drugs can cause death.
How to avoid
Teenager like to experiment drugs for various reasons from peer pressure , desire to appear grown up, boredom until curiosity. What would you do if someone offered you drugs? Especially when you are really sad or depressed?
Here are are some practical suggestion:
Stay clear of situations where people are likely to using drugs.
Be firm in your stand against drug. Always remember that drug abuse is illegal.

By : Astrid Prakasa

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Nervous System

Have you ever got your hand or any parts of your body touched a hot object? Of course, if that happens you will immediately withdraw from it. A living organism is able to react to the changes in the environment or surroundings. Any change in the environment that cause an organism to react is called stimulus, and an organism’s reaction to a stimulus is called response.

Now, this is the work of one of the most important systems in our body, The Nervous System. Nervous system is an organ system containing a network of specialized cells called neurons. The Nervous system is also divided into two parts, the central nervous system (CNS) that contains of the brain, spinal cord, and retina. The second one is the peripheral nervous system that consists of the cranial nerve from the brain and the spinal nerve from the spinal cord and sense organ.

The sense organs that receive stimuli, is called receptors. They inform the Central Nervous System of any change our surroundings, by producing electrical messages called nerve impulses. A nerve impulse is transmitted within a fraction of a second. In response to this stimulus, the CNS will send nerve impulses to the muscle, thus resulting an effect of action. The muscles are then called effectors.
The nervous system is made out of nervous tissues. There are the Sensory neuron, Motor neuron, and the Relay neuron. The sensory neuron is for sending the nerve impulses that is sent from the receptor to the brain or to the spinal cord. Motor neuron transmits nerve impulses from the central nervous system to the effectors or the effector. Relay neuron is for transmitting nerve impulses from the sensory neuron to the motor neuron.

Motor neuron are made out of Dendron, cell body, axon, Myelin Sheath, Neurilemma, Node of Ranvier, Dendrites of an axon, and Motor end Plate. Each and every single one of them has their own function. The sensory neuron has a circular cell body; it has only one long Dendron and a short axon.

Next is the Synapse and Motor end Plate. What are they you may ask? Well, Synapse is a junction between two neurons or a junction between a neuron and an effector such as a gland or muscle. Motor end Plate formed where the end branch of an axon encounter the muscle fibers. Nerve impulses are transmitted across the Motor end plate by chemicals that stimulate the muscle.

There are two regions in the brain and spinal cord. The Grey matter, that is located at the central part of the spinal cord and in the inner part of the brain, and The White matter, which is located in the outer part of the spinal cord and in the central part of the brain.

There’s also another thing that you should know about the Nervous system, and that is the Voluntary action and the reflex action. Action that is controlled by our will is called voluntary action; this voluntary action may and may not involve a receptor or sensory neuron. While Reflex action is an immediate response to a specific stimulus without conscious control. A reflex action is an involuntary action, which means that our body moves without us (or our brain) commanding them to, a movement that is not based on our will.

There are two types of reflex action, The spinal and cranial nerve reflexes. All this action occurs without any conscious effort, in fact sometimes it might be difficult to prevent them to react. The spinal reflex are controlled by the spinal cord, and cranial reflex are controlled by the brain (unconsciously) and usually occurs in the head region.

The nervous pathway is called the reflex arc. The reflex arc are consist of a receptor or sense organ, a sensory neuron, a relay neuron, a motor neuron, and an effector.

And that’s it about Nervous system, and to summarize all this you can watch this video right here:

~By: Nasya Joan

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Endocrine System

The human endocrine system is a complex biological messaging system. Just like the nervous system transmits messages throughout the body by releasing and receiving neurotransmitters along a pathway of nerves, the endocrine system releases chemical messengers called hormones which control … Continue reading

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