Biology Flashcards
What does the circulatory system do?
maintains stable body fluids, transports wastes and carbon dioxide away from the cells, transports food and oxygen to the cells, protect the body against diseases through WBC, distributes heat throughout the body, and carries chemical messages from one cell to another
What does the Heart function as?
A pump
What is the atria?
a chamber of the heart that receives blood from the body/lungs and passes it to a ventricle.
What is the ventricles?
The ventricle is a muscular, thick-walled heart chamber that pumps blood through the arteries.
What does the septum do?
The septum separates the ventricles and allows for proper blood flow through the heart
What does the right side of the heart do?
The right side is the pulmonary circulatory pump, moving CO2 rich-blood to the lungs to get oxygen and then systemic circulation
What does the left side of the heart do?
O2 rich-blood from the left side is pumped throughout the body.
What does the left and right atrium do?
The right atrium receives oxygen poor blood from the superior and inferior vena cava. The left atrium receives oxygen rich blood from the pulmonary veins
What does the left and right ventricles do?
The right ventricle passes oxygen poor blood to the pulmonary artery, which sends it to the lungs to make the oxygen poor blood become rich in oxygen. The left ventricle pumps oxygen rich blood to the body through a large network of arteries.
What does the Superior Vena Cava do?
The superior vena cava carries blood from the head, neck, arms, and chest
What does the Inferior Vena Cava do?
The inferior vena cava carries blood from the legs, feet, and organs in the abdomen and pelvis
What do the pulmonary arteries do?
The pulmonary arteries carry oxygen poor blood from the right or left side of the heart to the lungs.
What do the pulmonary veins do?
The pulmonary veins transfer oxygen rich blood from the lungs to the left atria of the heart
What does the Aorta do?
The main artery that transfers oxygen rich blood away from the heart and to the rest of the body
What does the Tricuspid Valve do?
The tricuspid valve separates the right atrium from the right ventricle. It allows blood to flow from the right atrium to the right ventricle. It also prevents the back flow of blood from the right ventricle to the right atrium.
What does the Mitral valve do?
The mitral valve keeps blood flowing in the right direction and prevents the back flow of blood
What do the Semilunar Valves do?
The semilunar valves determine the passage of blood between the ventricles and the main arteries. The semilunar valve transports oxygen rich blood away from the heart to the vital organs
What are the three Blood Vessels?
Arteries, Veins, and Capillaries
What are Arteries and what do they do?
Arteries carry blood away from the heart while the heart contracts and pushed blood into the arteries. Arteries are thick walled, elastic, and can stretch to accomodate blood, then recoil to help propel the blood (like a slingshot).
What are Capillaries and what do they do?
Capillaries are tiny vessels that link arterioles and venules. Capillaries are blood cells that must pass through single file (like kindergarden), composed of single layer of cells, and is the site of fluid and gas exchange between body and blood cells.
What are arterioles and what do they do?
Arterioles are smooth and elastic, they can undergo vasoconstriction which decreases in blood flow to tissue, and vasodilation which can increase the blood flow to tissues.
What are venules and what do they do?
Venules are small veins that collect the deoxygenated blood from the capillaries that go towards the heart.
What does oxygen do in Blood?
Oxygen diffuses out into surrounding tissue
What does oxygen do in Blood?
Oxygen diffuses out into surrounding tissue
What does Carbon dioxide do in blood?
carbon dioxide diffueses into capillaries
True or False: Blood velocity is Slow
True
Why is Blood Velocity Slow?
It allows time for exchange to occur
True or False: Diffusion is the least important for of transport
False
Why is diffusion the most important form of transportation?
DIFFUSION is the most important form of transport of molecules out of capillaries and into cells and vice versa.
True or False: Diffusion is always from low to high concentration
False
What are veins and what do they do?
Veins also contain valves that open in one direction to push blood back into the heart. Veins are aided by the skeletal muscles whose contractions increase the pressure in the veins and force the valves open which allows blood flow to the heart.
True or False: The heart is myogenic
True
Why is the heart myogenic?
It is able to contract spontaneously subconsciously.
How long does the cardiac cycle last?
0.8 seconds
How long does diastole and systole take?
0.4 seconds
How many beats per minute occur during the intrinsic control and how many litres of blood is pumped?
The intrinsic control beats approximately 72 times and pumps 5 litres of blood per minute.
Does the atria contract first and then the ventricles or vice versa?
The intrinsic control must coordinate these contractions which causes the atria to contract first, then the ventricles.
What are the two stages of the intrinsic control?
Diastole and systole
Where does diastole occur
The SA node
Where does systole occur
The AV node
Where is the SA node located and what does it do?
The SA node is located in the upper wall of the right atrium and is a specialized tissue in that it behaves like a nerve and a muscle so when it contracts, it also creates an electrical signal. The SA node generates a wave of electricity which causes both the atria and ventricles to contract at the same time.
True or False: The ventricles are relaxed while the atria contracts simultaneously
True. This forces blood from the atrium through the AV valve, and into the ventricles.
True or False: The ventricles pressure while it is relaxed is very high
False. The semilunar valves are closed and the pressure in the arteries while the ventricles are relaxed is very low
Where is the AV node located and what does it do?
AV node (atrioventricular node) which is located at the base of the right atrium and is just above the tricuspid valve. The AV node receives an electrical impulse from the SA node, but is delayed by 0.1 seconds. The AV node fires and send an electrical signal throughout the muscle tissue of both ventricles
Why is there a delay of 0.1 seconds in the AV node
It is delayed by 0.1 seconds so that blood can move from the contracted atria before initiating the ventricles to contract.
True or False: Systole occurs when the atria are contracted and the ventricles are relaxed
False. During systole, the atria are relaxed and both ventricles contract and force blood through the semilunar valve and out of the heart and towards the lungs and the system of the body.
What increases blood pressure
Decrease in diameter of blood vessels Increased amount of blood Eating fatty foods (fried foods) Eating cholesterol-rich foods Age
What decreases blood pressure
Exercise: increases in blood vessel diameter
Loss of blood = thinner blood
What is the risks of Hypertension (High Blood Pressure)?
heart attack, damage to kidneys and eyes, strokes.
What happens when people age?
Both systolic and diastolic blood pressures increase as people age. This causes the arteries to harden, become less active, and the muscles cannot stretch as well.
What is the Functions of Blood?
Carries oxygen to all cells
Carries nutrients to all cells
Carries wastes away from the cells, mainly to the lungs and kidneys
Helps regulate body temperature
Carries hormones throughout the body
Fights invading pathogen agents, such as bacteria and viruses
What does blood consist of?
Blood consists of cells, WBC, plasma, and platelets.
What does plasma do in blood?
Plasma carries nutrients to the cells and waste away from the cells. Plasma will move to areas that require healing.
What percent of plasma is in blood?
55%
What does plasma consist of?
92% water, 7% protein, 1% glucose, clotting factors, carbon dioxide hormones, and some salts.
What does a stethoscope do?
used to listen to lub/dub and the functioning of the heart valves
What medical instrument is used to measure the pressure exerted by the heart
sphygmomanometer
What is a pulse?
A surge of blood throughout the arteries which is caused by ventricular contraction (systole)
