The Circulatory System: Hearts and Blood Vessels Flashcards
Main functions of the circulatory system
- Transportation of gases, nutrients and wastes
- Regulation of internal temperature
- Protection against blood loss and disease
Main components of the circulatory system
Heart - an organ that pushes blood through the body with its pumping action
Blood vessels - pathways through which the blood moves
Blood - carries nutrients, oxygen, CO2, H2O, wastes and other materials throughout the body
What does a faulty heart result in?
Death
Functions of the heart
- Pumps blood throughout the body
- Keeps oxygenated (red) blood separated from deoxygenated (dull red, brownish colour) blood
Ensures blood flow is going in one direction
Functions of the heart
- Forces blood into arteries
- Walls made up of cardiac muscle (only found in the heart)
What is the pericardium?
A fluid filled sac that encloses the heart
What does the pericardium prevent?
Prevents friction between the heart and tissue around it
Composition of the heart
Two parallel pumps:
- right pump for deoxygenated blood
- left pump for oxygenated blood
RIGHT AND LEFT PUMPS CONTRACT SIMULTANEOUSLY
What is the septum?
A muscular wall that separates the right and left sides of the heart
(Chambers of the heart)
What does the atria (atrium singular) do?
- The upper chambers collects blood coming into the heart
- It pumps blood through the valves into the ventricles
Is the atria thick or thin-walled muscle?
Thin-walled muscle
What are ventricles in chambers of the heart?
- They are the lower chambers
- Thick-walled muscle
What do ventricles do?
They pump blood away from the heart
What is the vena cava?
Largest vein in the body
What does the superior vena cava do?
It carries deoxygenated blood to the heart from tissues in the head, chest and arms
