The heart is an amazing organ that keeps our body running smoothly by pumping blood. While it’s often mentioned in songs and poems, its main job is to keep blood moving, delivering nutrients and oxygen to every part of our body.
The heart is about the size of two fists put together and weighs between $250$ to $350$ grams. It sits in the middle of your chest, between your lungs, and is tilted slightly, with one end pointing towards your left hip and the other towards your right shoulder.
The heart is protected by a double-layered sac called the pericardium. This includes:
Between these layers is a fluid that helps the heart move smoothly as it beats.
The heart wall is made up of three layers:
The heart is divided into two sides by a thin wall called the septum, creating four chambers:
Each chamber has valves that make sure blood flows in the right direction and doesn’t go backward. The familiar “lub-DUB” sound of the heart is made by these valves opening and closing.
The heart uses two main loops to circulate blood: pulmonary circulation and systemic circulation.
Blood pressure measures how hard blood pushes against the walls of blood vessels. It’s shown as two numbers:
These numbers help us understand heart health. Unusual blood pressure can signal health problems like dehydration or high blood pressure, which can be serious.
The heart is a complex and efficient pump that keeps blood flowing throughout the body. Knowing how it works helps us appreciate the importance of heart health. By keeping our blood pressure in check and ensuring good circulation, we support the heart’s vital role in keeping us healthy.
Create a 3D model of the heart using clay or other craft materials. Focus on accurately representing the heart’s chambers, valves, and major blood vessels. Label each part and explain its function to your classmates.
Use an online simulation tool to explore how blood flows through the heart. Pay attention to the pathways of pulmonary and systemic circulation. Afterward, describe the journey of a red blood cell from the right atrium through the entire circulatory system and back.
Measure your resting heart rate and then perform a physical activity like jumping jacks for two minutes. Measure your heart rate again immediately after exercising. Record your observations and discuss how exercise affects heart rate and why this is important for heart health.
In pairs, take turns role-playing as a doctor and a patient. Use a mock blood pressure cuff to practice measuring blood pressure. Discuss what the systolic and diastolic numbers mean and how they relate to heart health.
Create a poster that highlights the importance of maintaining heart health. Include tips for keeping blood pressure in check, such as regular exercise, a balanced diet, and stress management. Present your poster to the class and explain why each tip is beneficial for the heart.
Heart – The muscular organ in the body that pumps blood through the circulatory system by rhythmic contraction and dilation. – The heart beats approximately 70 times per minute in a healthy adult.
Blood – The fluid that circulates in the heart, arteries, capillaries, and veins of a vertebrate animal, carrying nourishment and oxygen to and bringing away waste products from all parts of the body. – Red blood cells in the blood are responsible for transporting oxygen to various tissues.
Circulation – The continuous movement of blood through the heart and blood vessels, which is essential for maintaining homeostasis in the body. – Proper circulation ensures that all cells receive the nutrients and oxygen they need to function.
Oxygen – A gas that is brought into the body by the respiratory system and is essential for cellular respiration and energy production. – Oxygen is transported by hemoglobin in red blood cells to tissues throughout the body.
Chambers – The four sections of the heart, consisting of two atria and two ventricles, that receive and pump blood. – The left and right ventricles are the chambers responsible for pumping blood out of the heart.
Pressure – The force exerted by circulating blood on the walls of blood vessels, often measured as blood pressure. – High blood pressure can lead to serious health issues, such as heart disease.
Nutrients – Substances obtained from food that are vital for growth and maintenance of a healthy body. – Nutrients like vitamins and minerals are absorbed into the bloodstream during digestion.
Valves – Structures in the heart and veins that ensure blood flows in one direction and prevent backflow. – The mitral valve is one of the four valves in the heart that helps regulate blood flow.
Anatomy – The study of the structure of living organisms, particularly their physical form and arrangement. – In biology class, we learned about the anatomy of the human heart and its function in the circulatory system.
Health – The state of complete physical, mental, and social well-being, not merely the absence of disease or infirmity. – Regular exercise and a balanced diet are important for maintaining good health.
