Transport in Humans (Circulatory System)

Flashcards covering circulatory system concepts: transport substances, heart structure and function, cardiac cycle, valves, ECG/heart sounds, blood vessels, blood components, coronary disease, and exchange processes.

What substances need to be transported by the circulatory system in humans?

Food, oxygen and waste products (water and carbon dioxide).

What are the transport systems in humans as described in the notes?

The heart, blood (platelets, white blood cells, red blood cells, plasma), and blood vessels (veins, arteries, capillaries).

How is the circulatory system described in the learning objectives?

As a system of blood vessels with a pump (the heart) and valves to ensure one-way flow of blood.

What is double circulation?

A system in which blood passes through the heart twice for each complete circuit.

What are the two main circuits in the circulatory system?

Pulmonary circulation (to the lungs) and systemic circulation (to the rest of the body).

What are the main components of blood listed in the notes?

Red blood cells, white blood cells, platelets, and plasma.

What are the core parts of the transport system in humans?

Heart, blood, and blood vessels (veins, arteries, capillaries).

What is pulmonary circulation and why is it low pressure?

Flow of blood from the heart to the lungs; it is low pressure because the distance is short.

What is systemic circulation?

Flow of blood from the heart to the body tissues; high pressure due to longer distance.

How many chambers does the human heart have and what are they?

Four chambers: right atrium, right ventricle, left atrium, left ventricle.

Which chamber receives blood from the lungs?

Left atrium.

Which chamber pumps blood to the rest of the body?

Left ventricle.

Which chamber receives blood from the rest of the body?

Right atrium.

Which chamber pumps blood to the lungs?

Right ventricle.

Which vessels carry blood to the heart from the body?

Superior vena cava and inferior vena cava (veins).

Which vessels carry blood from the heart to the lungs?

Pulmonary artery.

Which vessels carry blood from the lungs to the heart?

Pulmonary veins.

Which vessel carries blood from the heart to the rest of the body?

Aorta.

How is oxygenated blood color-coded in the notes?

Red.

How is deoxygenated blood color-coded in the notes?

Blue.

Why is the left ventricle thicker than the right?

Because it pumps blood at higher pressure to the rest of the body.

Which valves control blood flow between atria and ventricles and between ventricles and arteries?

Atrioventricular valves (tricuspid and bicuspid/mitral) and semilunar valves (pulmonary and aortic).

What attaches AV valves to the ventricles?

Chordae tendineae (tendons) and papillary muscles.

What is the cardiac cycle?

Rhythmic contraction and relaxation of the heart producing one heartbeat (lub-dub).

What are the three main stages of the cardiac cycle?

Atrial systole, ventricular systole, diastole (atria and ventricles relax).

What causes the 'lub' sound?

Closure of the atrioventricular valves at the start of systole.

What causes the 'dub' sound?

Closure of the semilunar valves at the end of systole.

What is the purpose of the ECG?

To monitor the electrical activity of the heartbeat.

How can heart rate be monitored besides ECG?

By pulse rate and by listening to heart sounds.

What is the function of platelets?

To clot blood by converting soluble fibrinogen to insoluble fibrin, preventing blood loss.

What are the main components of blood and their basic roles?

Red blood cells (carry oxygen), white blood cells (fight infection), platelets (clotting), plasma (fluid carrying dissolved substances).

What are the key features of red blood cells?

Disc-shaped, biconcave, no nucleus, contain hemoglobin, transport oxygen.

What are white blood cells and their functions?

Different types; phagocytes engulf bacteria; lymphocytes produce antibodies.

What is plasma and what does it contain?

The liquid component, mostly water; carries nutrients, hormones, proteins, antibodies, and wastes.

What is the role of coronary arteries?

Supply blood to the heart muscles.

What is coronary heart disease?

Blockage of coronary arteries by fat deposits or clots, leading to heart attack.

What are common risk factors for coronary heart disease listed in the notes?

Smoking, high-fat diet, overweight, lack of exercise, stress.

How can the risk of coronary heart disease be reduced?

Avoid smoking, eat a healthy diet, exercise regularly, manage stress.

What are the three layers of arteries and veins?

Smooth lining, elastic tissue & muscle, connective tissue.

What is the role of capillaries?

Connect arteries and veins and allow exchange of substances between blood and tissue.

How does capillary exchange occur for oxygen/nutrients and carbon dioxide/wastes?

Oxygen and nutrients move from blood to tissue; carbon dioxide and wastes move from tissue to blood.

What is the role of the lymphatic system in circulation?

Drains excess tissue fluid from tissues into the lymphatic system.

What is tissue fluid and how is it related to capillaries?

Fluid bathing tissue cells derived from plasma; formed when plasma filters out of capillaries and returns to them; drains into lymphatics.

What processes change pressure in the heart during a beat (summary)?

Contraction and relaxation of atria and ventricles (systole and diastole) causing pressure changes; the coordinated valve actions produce the heart sounds.