8.8 - Heart and Circulatory System Structure And Function Flashcards
What is the heart?
The heart is an organ in the circulatory system.
What does the circulatory system do?
It carries oxygen and nutrients to every cell in the body and removes waste products.
What type of circulatory system does the heart use?
The heart pumps blood around the body in a double circulatory system.
What are the two circuits in the double circulatory system?
1: Deoxygenated blood flows to the lungs. 2: Oxygenated blood is pumped around the body.
What happens to deoxygenated blood in the heart?
It flows into the right atrium, then into the right ventricle, which pumps it to the lungs.
What happens to oxygenated blood in the heart?
It flows into the left atrium, then into the left ventricle, which pumps it around the body.
What are the main structural features of the heart?
Muscular walls, 4 chambers, valves, and coronary arteries.
Why is the muscular wall of the left ventricle thicker?
Because it needs to pump blood all around the body, unlike the right ventricle.
What is the process of blood flow in the heart?
- Blood flows into the right atrium through the vena cava, and left atrium through the pulmonary vein. 2. Atria contract, forcing blood into the ventricles. 3. Ventricles contract, pushing blood to the lungs and around the body. 4. Valves close to prevent backflow.
What controls the natural resting heart rate?
A group of cells in the right atrium act as a pacemaker, providing electrical impulses.
What is the average resting heart rate?
Around 70 beats per minute.
What is an artificial pacemaker?
An electrical device that produces a signal to regulate heartbeats.
When is an artificial pacemaker used?
If an individual has an irregular heartbeat.
