1.7 Circulatory System Flashcards
What is the primary function of the circulatory system?
To transport materials through the body toward and away from particular organs and tissues.
What are the components of the circulatory system?
- Heart
- Blood vessels
- Blood
What are the two types of circulation in the double circulation system?
- Pulmonary circulation
- Systemic circulation
What do arteries carry?
Oxygenated blood away from the heart.
Why is high pressure important in arteries?
It ensures blood can travel efficiently over long distances to supply oxygen and nutrients to tissues.
What role do capillaries play in the circulatory system?
They allow the exchange of molecules between blood and the body’s cells.
Fill in the blank: Capillaries are small blood vessels that connect ______ and ______.
arterioles, venules
What happens at the arterial end of capillaries?
There is a higher concentration of oxygen and nutrients.
What is the function of veins?
To return deoxygenated blood back to the lungs.
True or False: Valves in veins prevent blood from flowing in the wrong direction.
True
What is the composition of blood plasma?
Approximately 90% water and 10% dissolved substances including proteins, salts, minerals, glucose, lipids, and cell waste.
What are platelets and their function?
Tiny blood cells that stop bleeding and form blood clots.
What is the shape of red blood cells and why is it significant?
Biconcave shape, providing a large surface area for oxygen and carbon dioxide transport.
What are the two types of white blood cells?
- Lymphocytes
- Phagocytes
What is extracellular fluid (ECF)?
The body fluid that exists outside of cells.
What percentage of ECF returns to capillaries at the venule end?
90%
What does the lymphatic system do?
Returns protein and excess ECF to the circulatory system near the heart.
Fill in the blank: The ______ carries deoxygenated blood from the heart to the lungs.
pulmonary artery
What is the role of the left ventricle?
To pump oxygenated blood to all organs.
What is the function of the valves in the heart?
To maintain the direction of blood flow and prevent backflow.
What happens to carbon dioxide in the blood?
It is picked up by dissolving into plasma and by binding to hemoglobin for transport to the lungs.
What is fibrin and its role in blood clotting?
A network of protein fibers that forms a structural basis for stopping bleeding and sealing wounds.
What is the significance of the heart being made up of cardiac muscle?
It allows for coordinated contraction and efficient blood pumping.
How do capillaries maximize the exchange of materials?
- Higher concentration of oxygen and nutrients at the arterial end
- High concentration of carbon dioxide and waste products at the venous end
- Thin walls for shorter diffusion distance
- Increased surface area from the capillary network
