biology - circulatory system

what are the major components of the circulatory system?

the heart, blood, and blood vessels

what are the major functions of the circulatory system?

1. delivering needed materials such as oxygen, glucose, hormones, and nutrients to the cells of the body

2. carrying waste products such as carbon dioxide from cells back into the lungs

3. fighting disease by transporting white blood cells throughout the body

4. distributing heat throughout the body

what is the function of blood vessels?

to act as transport "tubes" for blood

what are blood vessels made up of?

living cells and tissues

how many miles of blood vessels do you have in your body?

60,000 miles

what are arteries?

blood vessels that bring oxygen-rich blood from your heart to all of your body's cells

what direction does blood flow in arteries?

away from the heart

what is the oxygen concentration in arteries?

blood is oxygenated (with 1 exception)

what is the pressure inside of arteries?

high

what is the thickness of the walls in arteries?

very thick

are there valves present in arteries?

no valves are present

what is the outermost layer of an artery/vein?

the connective tissue

what is the middle layer of an artery/vein?

smooth muscle

what is the innermost layer of an artery/vein?

endothelium

what are veins?

blood vessels located throughout your body that collect oxygen-poor blood and return it to your heart

what direction does blood flow in veins?

back to the heart

what is the oxygen concentration in veins?

blood is deoxygenated (with 1 exception)

what is the pressure inside of veins?

low

what is the thickness of the walls of veins?

thinner than arteries

are valves present in veins?

yes, there are one way valves

what are capillaries?

microscopic vessels where there is an exchange of CO2 and O2 substances with cells

what direction does blood flow in capillaries?

from arteries to veins

what is the pressure inside of capillaries?

extremely low

what is the thickness of the walls of capillaries?

very thin

are valves present in capillaries?

no there are no valves present

what is the only layer of a capillary?

the endothelium

why are capillaries so thin?

so simple diffusion of CO2 and O2 can occur

what % of blood is made up of plasma?

55%

what is the function of plasma?

to transport blood cells, nutrients, hormones, and proteins throughout the body, maintain blood pressure and volume, and support blood clotting and immune function

where is plasma produced?

partially in the liver and in bone marrow

(do not quote me please keith did not teach us this and google has 30 different answers)

what does plasma look like?

it is a straw colored liquid

what % of blood is made up of red blood cells?

45%

what is the function of red blood cells?

to transport oxygen from your lungs to your body's tissues

where are red blood cells produced?

in bone marrow

what is hemoglobin?

the protein responsible for carrying oxygen in red blood cells

what % of blood is white blood cells?

<1%

what is the function of white blood cells?

defending the body against infections and diseases

where are white blood cells produced?

in bones

what % of blood is platelets?

<1%

what is the function of platelets?

stopping and preventing further bleeding in the site of a wound

where are platelets produced?

in bones

what are stem cells?

cell with the potential to develop into many different types of cells in the body

what is the function of stem cells?

to serve as the repair system for the body

what are the two main types of stem cells?

embryonic and adult

how are stem cells different from other cells?

1. they can divide and renew themselves over a long period of time

2. they are unspecialized, so they cannot do specific functions in the body

3. they have the potential to become specialized cells such as muscle cells, blood cells, and brain cells

how many chambers are in the heart?

4

what are the two upper chambers of the heart called?

atria

what are the two lower chambers of the heart called?

ventricles

your heart is about the size of your fist and very __________________

muscular

what kind of blood does the left atrium receive?

oxygenated blood

what kind of blood does the right atrium receive?

deoxygenated blood

what do the ventricles do with the blood they receive?

they pump it to the lungs or to the rest of the body

what muscular wall separates the left and right atrium?

the septum

what way does blood flow?

in the same direction

what do valves do?

they prevent blood from flowing in the opposite direction

what are the names of the valves?

(in order from right atrium to left)

1. tricuspid valve

2. pulmonary semilunar valve

3. aortic semilunar valve

4. mitral valve

blood pathway of deoxygenated blood

right atrium ---> tricuspid valve ---> right ventricle ---> pulmonary valve ---> pulmonary artery ---> lungs

blood pathway of oxygenated blood

lungs ---> pulmonary vein ---> left atrium ---> mitral valve ---> left ventricle ---> aortic valve ---> aorta

what artery carries deoxygenated blood (the 1 exception)

the pulmonary artery

what vein carries oxygenated blood (the 1 exception)

the pulmonary vein

what is the heart's natural pace maker?

the sinoatrial node (SA)

what part of the brain controls the heart rate?

the medulla oblongata

where can you feel your pulse?

your neck, top of foot, and wrist

what is the average resting pulse?

60/80 beats per minute

when can fetal heart rate be detected in the womb?

as early as 6 weeks

what is blood pressure?

the measure of the pressure against blood vessel walls

what is a typical blood pressure?

120/80 beats per minute

what is high blood pressure called?

hypertension

what is arteriosclerosis?

when blood clots or plaques partially or fully block one of the coronary arteries that provide the heart with O2

what is a heart attack?

when blood flow to the heart muscle is blocked, preventing the heart from receiving oxygen (also called myocardial infarction)

what is arrhythmia

an abnormal heart rhythm, irregular heart beat

what is a stroke?

when a blood vessel providing the brain with oxygen and nutrients bursts and is blocked

what is the thickness of the walls in arteries?

very thick