SCIENCE04L02: The Heart
OBJECTIVES
To describe the parts and the functions of the heart
To explain how the parts of the heart work together to make the body
function properly
To name the different diseases that affect the heart
To show proper care for the heart
To practice habits to maintain a healthy heart
LESSON PREREQUISITE
LESSON PROPER
The Heart and Its Functions
The pulse or heartbeat is the thumping movement you feel whenever your
heart pumps blood. You may feel it strongest at your wrists. The pulse or pulse rate is also the number of your heartbeats for every minute or 60 seconds.
Your heart is muscle organ placed almost near the center of your chest. It is almost of the same size as your fist. Like your other muscles, the heart performs a special movement. Its task is to continuously pump blood. Every minute, your heart pumps about five (5) to six (6) liters of blood to your body.
The heart performs two main blood pumping tasks:
1. To pump blood from the heart to different parts of the body
2. To pump deoxygenated blood to the lungs
The blood is an important material that brings nutrients, especially oxygen, to different parts of the body. It also collects waste materials from the parts of the body it visits. The blood needs the help of the heart so it can flow smoothly around the body.
When the blood carries oxygen, it is called oxygenated blood. Oxygenated
blood comes from the heart and goes to the different body parts. When the blood gives the oxygen to the different body parts and collects wastes like carbon dioxide, it becomes deoxygenated blood. When deoxygenated blood reaches the heart, the heart pumps it, so it can go to the lungs. The lungs are body organs that help us get oxygen from air and release carbon dioxide. In the lungs, the blood leaves carbon dioxide and collects oxygen.
Parts of the Heart Working Together
The different parts of the heart help perform its tasks. It has major blood
vessels that bring blood toward and away from the heart. It has chambers that receive blood and perform the pumping action. It has valves that keep the direction of blood flow inside the heart.