Circulatory System Flashcards
What is the primary function of the circulatory system?
The primary function of the circulatory system is to transport oxygen, nutrients, hormones, and waste products throughout the body. It also plays a role in regulating body temperature and protecting the body from infections.
What are the main components of the circulatory system?
Heart – A muscular organ that pumps blood throughout the body.
Blood vessels – arteries, veins, and capillaries that carry blood.
Blood – A fluid containing red blood cells, white blood cells, platelets, and plasma.
What is the difference between a open and closed circulatory system?
Open - no distinction between blood and interstitial fluid (eg. insects)
Closed - distinction between blood and interstitial fluid - blood stays in blood vessels ( eg. humans)
What is hemolymph?
general body fluid
What is the structure of the heart?
Right atrium
Left atrium
Right ventricle
Left ventricle
What are the heart valves and their voles?
tricuspid, pulmonary, mitral, and aortic
ensure that blood flows in only one direction, preventing backflow during the contraction and relaxation of the heart.
What does the right atrium do?
receives deoxygenated blood
What does the left atrium do?
receives oxygenated blood
What does the right ventricle do?
pumps deoxygenated blood to the body
What does the left ventricle do?
pumps oxygenated blood to the rest of body
What is the sinoatrial (SA) node?
It initiates electrical impulses that regulate the heart’s rhythm, causing the atria to contract and setting the pace for the heartbeat.
What is the function of arteries?
Arteries are blood vessels that carry oxygenated blood from the heart to the body. They have thick, elastic walls to withstand high pressure.
What is the function of veins?
Veins carry deoxygenated blood back to the heart. They have thinner walls and often contain valves to prevent blood from flowing backward due to low pressure.
What are capillaries?
Capillaries are tiny blood vessels where the exchange of oxygen, nutrients, and waste products occurs between the blood and surrounding tissues. They are the smallest blood vessels with very thin walls to facilitate diffusion.
What is blood pressure?
Blood pressure is the force exerted by circulating blood on the walls of blood vessels. It is highest in the arteries when the heart contracts and lowest when the heart relaxes
What is systolic mean?
the heart contracts
What does diastolic mean?
the heart relaxes
What is the role of hemoglobin?
Hemoglobin is a protein found in red blood cells that binds to oxygen in the lungs and carries it through the bloodstream to tissues.
What are the components of blood?
Red blood cells
White blood cells
Platelets
Plasma
What does the red blood cell do?
carry oxygen using hemoglobin
What does the white blood cells do?
part of the immune system, used for defending against infections
What are platelets?
Help in blood clotting
What is plasma?
The liquid part of blood made of water, proteins, nutrients, hormones and waste
What is a pulmonary circulation?
refers to the path low oxygenated blood takes to pick up oxygen from lungs. (right ventricle to the lungs and back to the left atrium)
What is the systemic circulation?
refers to the flow of oxygenated blood to the rest of the body (left ventricle to the body )
What is pulmocutaneous circulation?
type of circulatory system where the blood is directed to both the lungs and the skin for gas exchange. Typically found in amphibians and some fish.
What id double circulation?
oxygen poor blood and oxygen rich blood are pumped from different sides of the heart
What is the coronary circulation?
circulation of blood that supplies the heart muscle. The coronary arteries deliver oxygen and nutrients to the heart tissue, and the coronary veins remove deoxygenated blood.
What is heart rate?
number of beats per minute
what is stroke volume?
amount of blood pumped in one contraction
What is cardiac output?
volume blood pumped into systematic circulation per minute
What is cardiac cycle?
heart contracts and relaxes in rhythm
What is systolic pressure?
pressure in the arteries during the ventricular systole
What is diatonic pressure?
pressure in the arteries during diastole (lower than systolic pressure)
What is the difference between vasodilation and vasoconstriction?
Vasodilatation - the relaxation of smooth muscles in arterioles (lowers blood pressure)
Vasoconstriction - contraction of smooth muscle in arteriole walls (increases blood pressure)
What 2 mechanisms regulate the distribution of blood in capillary beds?
- contraction of smooth muscle in the wall of an arteriole constricts the blood vessel
- precapillary sphincters control the flow of blood between the arterioles and the venules
What is a heart attack?
A heart attack occurs when a coronary artery becomes blocked, preventing oxygen from reaching part of the heart muscle. This leads to damage or death of the muscle tissue.
What is hypertension?
high blood pressure
occurs when blood pressure remains consistently elevated
What is stroke?
A stroke occurs when there is a disruption of blood flow to the brain, either due to a blocked or ruptured artery. This deprives brain cells of oxygen and can lead to brain damage.
What is cardiovascular disease?
disorder of heart and blood vessels caused by a buildup and backup of plaque in the arteries
what is low density lipoproteins?
“bad cholesterol” causes plaque formation
What is high density lipoproteins?
reduced disposition of cholesterol
What is the blood clotting process?
Blood clotting (coagulation) is a series of events where platelets and proteins in the blood work together to form a clot at the site of injury, stopping bleeding. The process involves fibrin, a protein that helps form a mesh over the wound.
