Human Heart — Interactive NEET Biology Visual Lab
The human heart is a four-chambered muscular pump that drives double circulation — the right side sends deoxygenated blood to the lungs, and the left side pumps oxygenated blood to the whole body. Tap any structure in the interactive model below to see what it does, in plain English and with an exam-accurate NEET note.
Explore the human heart — tap any part
Tap a structure to see what it does in plain English plus an exam-accurate NEET note, or hit Guided tour to be walked through it step by step.
Human Heart
Circulatory system
Selected structure
Human Heart
The human heart is a fist-sized muscular pump with four chambers. It runs a double loop: the right side sends oxygen-poor blood to the lungs, and the left side pumps oxygen-rich blood to the whole body. Tap any part, or take the guided tour.
NEET note
▸ All structures & functions
- Vena Cava
- Two large veins that drain used, oxygen-poor blood from the whole body back into the heart.
- NEET:Superior & inferior vena cava return deoxygenated blood to the right atrium.
- Right Atrium
- The top-right chamber. It collects oxygen-poor blood arriving from the body.
- NEET:Receives deoxygenated blood via the vena cava and passes it to the right ventricle.
- Tricuspid Valve
- A one-way door between the right chambers that stops blood flowing backward.
- NEET:Right atrioventricular valve; prevents backflow from the right ventricle to the right atrium.
- Right Ventricle
- Pumps the oxygen-poor blood the short distance to the lungs to pick up oxygen.
- NEET:Pumps deoxygenated blood into the pulmonary artery toward the lungs.
- Pulmonary Artery
- Unlike most arteries, the pulmonary artery carries deoxygenated blood from the right ventricle to the lungs.
- NEET:Carries deoxygenated blood from the right ventricle to the lungs — the exception to arteries carrying oxygenated blood.
- Pulmonary Veins
- Bring fresh blood from the lungs back to the heart — the exception to veins carrying oxygen-poor blood.
- NEET:Carry oxygenated blood from the lungs to the left atrium — the exception to veins carrying deoxygenated blood.
- Left Atrium
- The top-left chamber. It collects fresh, oxygen-rich blood returning from the lungs.
- NEET:Receives oxygenated blood from the lungs via the pulmonary veins.
- Bicuspid (Mitral) Valve
- A one-way door between the left chambers, keeping blood moving forward.
- NEET:Left atrioventricular (mitral) valve; prevents backflow from the left ventricle to the left atrium.
- Left Ventricle
- The strongest chamber — it pumps oxygen-rich blood out to the entire body.
- NEET:Thickest muscular wall; pumps oxygenated blood into the aorta to the whole body.
- Aorta
- The body's largest artery — the main highway carrying fresh blood out to everywhere.
- NEET:Largest artery; carries oxygenated blood from the left ventricle to the whole body.
- Septum
- The wall down the middle that keeps fresh and used blood from mixing.
- NEET:Muscular partition separating the left and right sides of the heart.
Human Heart: structures & functions
A quick, exam-focused reference for every structure in the human heart — each with a plain-English answer and the precise NEET point.
What is the vena cava?
Two large veins that drain used, oxygen-poor blood from the whole body back into the heart. Superior & inferior vena cava return deoxygenated blood to the right atrium.
What is the right atrium?
The top-right chamber. It collects oxygen-poor blood arriving from the body. Receives deoxygenated blood via the vena cava and passes it to the right ventricle.
What is the tricuspid valve?
A one-way door between the right chambers that stops blood flowing backward. Right atrioventricular valve; prevents backflow from the right ventricle to the right atrium.
What is the right ventricle?
Pumps the oxygen-poor blood the short distance to the lungs to pick up oxygen. Pumps deoxygenated blood into the pulmonary artery toward the lungs.
What is the pulmonary artery?
Unlike most arteries, the pulmonary artery carries deoxygenated blood from the right ventricle to the lungs. Carries deoxygenated blood from the right ventricle to the lungs — the exception to arteries carrying oxygenated blood.
What are the pulmonary veins?
Bring fresh blood from the lungs back to the heart — the exception to veins carrying oxygen-poor blood. Carry oxygenated blood from the lungs to the left atrium — the exception to veins carrying deoxygenated blood.
What is the left atrium?
The top-left chamber. It collects fresh, oxygen-rich blood returning from the lungs. Receives oxygenated blood from the lungs via the pulmonary veins.
What is the bicuspid (mitral) valve?
A one-way door between the left chambers, keeping blood moving forward. Left atrioventricular (mitral) valve; prevents backflow from the left ventricle to the left atrium.
What is the left ventricle?
The strongest chamber — it pumps oxygen-rich blood out to the entire body. Thickest muscular wall; pumps oxygenated blood into the aorta to the whole body.
What is the aorta?
The body's largest artery — the main highway carrying fresh blood out to everywhere. Largest artery; carries oxygenated blood from the left ventricle to the whole body.
What is the septum of the heart?
The wall down the middle that keeps fresh and used blood from mixing. Muscular partition separating the left and right sides of the heart.
Frequently asked questions
What is the vena cava?
Two large veins that drain used, oxygen-poor blood from the whole body back into the heart. Superior & inferior vena cava return deoxygenated blood to the right atrium.
What is the right atrium?
The top-right chamber. It collects oxygen-poor blood arriving from the body. Receives deoxygenated blood via the vena cava and passes it to the right ventricle.
What is the tricuspid valve?
A one-way door between the right chambers that stops blood flowing backward. Right atrioventricular valve; prevents backflow from the right ventricle to the right atrium.
What is the right ventricle?
Pumps the oxygen-poor blood the short distance to the lungs to pick up oxygen. Pumps deoxygenated blood into the pulmonary artery toward the lungs.
What is the pulmonary artery?
Unlike most arteries, the pulmonary artery carries deoxygenated blood from the right ventricle to the lungs. Carries deoxygenated blood from the right ventricle to the lungs — the exception to arteries carrying oxygenated blood.
What are the pulmonary veins?
Bring fresh blood from the lungs back to the heart — the exception to veins carrying oxygen-poor blood. Carry oxygenated blood from the lungs to the left atrium — the exception to veins carrying deoxygenated blood.
What is the left atrium?
The top-left chamber. It collects fresh, oxygen-rich blood returning from the lungs. Receives oxygenated blood from the lungs via the pulmonary veins.
What is the bicuspid (mitral) valve?
A one-way door between the left chambers, keeping blood moving forward. Left atrioventricular (mitral) valve; prevents backflow from the left ventricle to the left atrium.
What is the left ventricle?
The strongest chamber — it pumps oxygen-rich blood out to the entire body. Thickest muscular wall; pumps oxygenated blood into the aorta to the whole body.
What is the aorta?
The body's largest artery — the main highway carrying fresh blood out to everywhere. Largest artery; carries oxygenated blood from the left ventricle to the whole body.
What is the septum of the heart?
The wall down the middle that keeps fresh and used blood from mixing. Muscular partition separating the left and right sides of the heart.
Get the full NEET Lab — free.
The human heart is one of many interactive Visual Labs in the NEET Lab Android app, which covers Physics, Chemistry and Biology plus MCQ practice. Free, works offline after install, no account required.
Get it on Google Play