Answer the questions.

1. How many types of blood cells does the blood contain? Name them. 2. Where are blood cells made? 3. How do we also call red blood cells? Describe them. 4. What important protein do RBCs contain? 5. When does blood get its bright color? 6. What is the main function of white blood cells? 7. The blood contains far fewer WBCs than red cells, doesn't it? 8. When does the body increase production of WBCs? 9. What do we need platelets for? 10. What is plasma? 11. What other important substances does blood contain?

HEART ATTACK

Notes:

¹ squeezing — стиснення, здавлювання

² lightheadedness — запаморочення

³ nutrition — харчування

Each year over a million peo­ple in the U.S. have a heart attack. About half of them die. Many people have permanent heart damage or die because they don't get help imme­diately. It's important to know the symptoms of a heart attack. Those symptoms include: shortness of breath, chest discomfort — pressure, squeezing¹, or pain, discomfort in the upper bo­dy — arms, shoulder, neck, back, nausea, vomiting, dizziness, sweating, lightheadedness².

Most heart attacks happen when a clot in the coronary artery blocks the supply of blood and oxygen to the heart. Often this leads to an irregular heartbeat — called an arrhythmia — that causes a severe decrease in the pumping function of the heart. A blockage that is not treated within a few hours causes the affected heart muscle to die.

Heart attacks occur most often as a result of a condition called coronary artery disease (CAD). In CAD, a fatty material called plaque builds up over many years on the inside walls of the coronary arteries (the arteries that supply blood and oxy­gen to your heart). Eventually, an area of plaque can rupture, causing a blood clot to form on the surface of the plaque. If the clot becomes large enough, it can mostly or completely block the flow of oxygen-rich blood to the part of the heart muscle fed by the artery.

During a heart attack, if the blockage in the coronary artery isn't treated quick­ly, the heart muscle will begin to die and be replaced by scar tissue. This heart damage may not be obvious, or it may cause severe or long-lasting problems. Se­vere problems linked to heart attack can include heart failure and life-threatening arrhythmias (irregular heartbeats).

Acting fast at the first sign of heart attack symptoms can save your life and limit damage to your heart. Treatment is most effective when started within 1 hour of the beginning of symptoms. If you think you or someone you know may be hav­ing a heart attack:

• Call an ambulance within a few minutes — 5 at the most — of the start of symptoms.

• If your symptoms stop completely in less than 5 minutes, still call your doc­tor.

• Take only an ambulance to the hospital. Going in a private car can delay treatment.

• Take a nitroglycerin pill if your doctor has prescribed this type of medicine. Once at the hospital, doctors can perform several tests to quickly determine if the person is having or has had a heart attack and the best course of action to restore blood flow.

Each year, about 1.1 million people in the United States have heart attacks, and almost half of them die. CAD, which often results in a heart attack, is the lead­ing killer of both men and women in the United States. Many more people could recover from heart attacks if they got help faster. Of the people who die from heart attacks, about half die within an hour of the first symptoms and before they reach the hospital.

But you can help reduce your risk of heart disease by taking steps to control fac­tors that put you at greater risk. Heart-healthy nutrition³, daily physical activity, elimi­nating tobacco, controlling diabetes and a commitment to follow your healthcare professional's recommendations (including for cholesterol and high blood pressure) are all part of reducing your risk for heart disease, heart attack and stroke.

Date: 2016-04-22; view: 900