Anatomy- Unit 5: Cardiovascular System

The human heart pumps _______ of human blood through the body each day.

7,000 liters

Contracts about ________________ in an average lifetime

3 billion times

Blood circulates throughout the entire body in ____________

1 minute

What word do we use when referring to lungs?

pulmonary

What work do we use when referring to blood traveling around the entire body?

systematic

When we are referring to the heart, what word do we use?

cardiac, cardio, cardial

What is a blood vessel?

• arteries (takes blood away from the hear, arteries away)

• veins (takes blood to the heart)

A blood vessel that takes blood AWAY from the heart?

arteries

A blood vessel that takes blood TO the heart?

veins

visceral (organ) pericardium

Membrane that surrounds the heart

parietal (walls) pericardium

Membrane on the walls surrounding the heart

Pericardial cavity (hollow space)

Space between the heart and walls

• Space between the two membranes

Image to study

Blood supply to heart wall

• The heart is a huge muscle

• All muscles need blood to survive (because blood carries oxygen).

• Thus the heart needs blood as well

Coronary Arteries

The blood vessels that take OXYGENATED blood to the heart wall (away from inside of heart)

Coranary Veins

The blood vessels that take Deoxygenated blood away from the heart wall, back to the inside of the heart

Heart size varies with _______

Body size

Base

Top of the heart

Apex

bottom of the heart

Interventricular sulcus

Between ventricles

Auricles

• Ear-like flaps on either side of atrium

• Where the atrium are

Wall of the heart

3 distinct layers make up the wall of the heart -epicardium -myocardium -endocardium

epicardium

most superficial wall of the heart

myocardium

middle layer of the wall heart

endocardium

deepest layer

Heart has ____ chambers and they are _________________?

4 chambers; 2 atriums and 2 ventricles

Atrium

2 upper chambers (right and left) -small -thin walls of muscle

ventricles

2 lower chanbers (right and left) -larger -think walls of muscle Left ventricle wall is very THICK

Blood vessels attached to atriums

• Superior Vena Cava

• Inferior Vena Cava -Pulmonary Veins

Superior Vena Cava and Inferior Vena Cava both _________.

Lead to the right atrium

plumonary veins

Lead to the left atrium

Blood vessels attached to ventricles

• Aorta

• Pulmonary Artery

Aorta

becomes arteries - left ventricle - all blood gets pumped out of this vessel to the body

Pulmonary Artery

right ventricle -vessel for blood getting pumped to the lungs

valves

a devise that regulates the flow of fluids

2 tyes in a human heart: A-V and Semilunar

A-V (Atrioventricular) Valves:

Tricuspid Valve and Bicuspid Valve (mitral valve)

Tricuspid Valve:

Between Right Atrium and Right Ventricle Three leaflets

Bicuspid Valve (mitral valve):

Between Left Atrium and Left Ventricle Two leaflets

Chordae Tendinae:

Attached to each valve

Papillary Muscles:

Muscles that attach to Chordae Tendinae

Semilunar Valves:

Pulmonary Valve and Aortic Valve

Pulmonary valve

At base of Pulmonary Artery Prevents backflow

Aortic Valve

At base of Aorta Prevents backflow

Septum = wall

Interatrial Septum and Interventricaular septum

Interatrial septum

Structure that separates the right and left atrium

Interventricular septum

Structure that separates the right and left ventricles

There is always ________________ and ______________ in all of your blood vessels and always in your body

carbon dioxide and oxygen

Oxygenated blood

Blood that is oxygen RICH! In other words, it has a lot of oxygen and little carbon dioxide

Deoxygenated blood

Blood that is carbon dioxide RICH! In other words, it has a lot of carbon dioxide and little oxygen

VAVALVAVA

V-vena cava A-Right atrium (tricuspid valve) V-right ventricle (pulmonary valve) A- Pulmonary Artery L-Lungs V-pulmonary vein A-left atrium (bicuspid valve) A-aorta

1 - Deoxygenated blood enters the heart through the_______________

SUPERIOR and INFERIOR Vena Cavas -Superior Vena Cava brings blood TO the heart from the upper half of the body -Inferior Vena Cava brings blood TO the heart from the lower half of the body

2 - Deoxygenated blood enters the ___________ from the Superior and inferior vena cavas

Right Atrium

3 - Deoxygenated blood goes through the _____________ to the _______ Ventricle

Tricuspid valve ; Right

Tricuspid valve

Tricuspid valve prevents backflow to the right atrium (prevents blood coming back into right atrium by closing)

4 - Pulmonary arterty

Deoxygenated blood goes through the PULMONARY VALVE to the Pulmonary Artery.

Pulmonary valve

Pulmonary valve prevents backflow to the right ventricle (prevents blood coming back into right ventricle by closing)

5 - Lungs

Deoxygenated blood goes to the Lungs where carbon dioxide leaves the blood and goes into the lungs (to be exhaled) and oxygen (which was inhaled) enters into the blood. The blood is now oxygenated blood

pulmonary veins

Oxygenated blood travels to the heart in the Pulmonary Veins

All arteries are not _______

red

All veins are not ________

blue

6 - Left atrium

Oxygenated blood enters the Left Atrium

7 - Left ventricle

Oxygenated blood goes through the BICUSPID VALVE to the Left Ventricle

• This is why the left ventricle has such a HUGE MUSCULAR WALL, it needs to pump the blood out to the entire body!!!

Bicuspid valve

Bicuspid valve prevents backflow to the left atrium (prevents blood coming back into left atrium by closing)

Aortic valve

Aortic valve prevents backflow to the right ventricle (prevents blood coming back into right ventricle by closing)

8 - Aorta

Oxygenated blood goes through the AORTIC VALVE to the Aorta.

Valves A-V open when _____________

the papillary muscles pull on the chordae tendineae to open the leaflets

The semilunar valves open by

pressure from the blood when the ventricles contract

General Arteries

• take blood away from the heart

• aorta is the largest artery in the body

General Capillaries

• EXCHANGE occurs at capillaries (things can enter into the blood and leave the blood)

• Arteries turn into capillaries at organs

• Capillaries wrap around organs of the body where exchange of oxygen/carbon dioxide and nutrients/wastes occur

General Veins

• Veins lead blood TO the heart

• Capillaries turn into veins to bring deoxygenated blood back to the heart

• All veins eventually lead into the Superior and Inferior Vena Cavas

• Superior Vena Cava brings blood TO the heart from the upper half of the body

• Inferior Vena Cava brings blood TO the heart from the lower half of the body

image of capillaries

Circuits

a path that is repeated

pulmonary circuit

• Sends deoxygenated blood to lungs to get oxygen and get rid of carbon dioxide.

• Consists of: Pulmonary Artery Lungs Pulmonary Veins

Systemic Circuit

• Sends oxygenated blood to the body organs and removes wastes (carbon dioxide).

• Consists of: Aorta General arteries General capillaries General veins Superior/inferior vena cava

path of the blood image

Blood vessels are ________________ of the cardiovascular system

organs

Blood vessels include ______ and do __________

• Arteries

• Arterioles

• Capillaries

• Veins

• Venules

• Carry blood to and from heart

Arteries:

• Strong and most elastic vessels

• Carry blood away from the heart with high pressure

Arterioles:

Arteries that are subdivided into smaller, thinner, finer branched tubes -Second highest Pressure

Arteries have three walls:

Inner layer: Smooth surface which allows blood cells and platelets to flow without damage Middle Layer: Arterial wall of smooth muscle which contracts and shrinks blood vessel when necessary Outer Layer: Connective tissue

Diameter of the arteries changes because of ____________

The sympathetic nervous system - fight or flight response

• Middle leayer of smooth muscle contracts

Vasoconstriction

reduce diameter - increases bp

Vasodilation

increases diameter - decrease bp

Capillaries:

• Smallest diameter blood vessels

• Connects arterioles to venules

• Walls are thin in order for substances to pass through

• Blood moves the slowest here

• Wrap around organs to exchange with them

Capillaries exchange _________

Gases - O2 to CO2 Nutrients - carbs, proteins, fats, vitamins, minerals, and water to waste

Precapillary Sphincters

• Arteriols have precapillary sphincters on them

• The sphincters constrict to allow less blood to flow to an area of the body or vice versa

Sphincter

Round smooth muscle that constricts, involuntary

Veins

• Carry blood to the heart

• Follow pathways that roughly parallel the arteries of the body

• Thinner walls than arteries

Venules:

Small, fine blood vessels that branch off from capillaries and lead to veins

Valves:

• Many veins have valves

• Usually composed of two leaflets.

• They are pushed close if the blood begins to back up in a vein.

• Aid in returning blood to heart

• Veins have the lowest pressure so they control the flow of the blood back the heart so that there is not a back up

Major Arteries:

• Aorta

• Abdominal Aorta

• Carotid

• Brachial

• Femoral

Major Veins

• Superior vena cava

• Inferior vena cava

Heart contractions:

• contract in a coordinated fashion

• Atriums first then ventricles

• When a section is contracting it is called systole

• When the section is relaxed (while the other one is contracting) it is called diastole

Cardiac Cycle:

1. Atrial systole

2. Ventricular diastole

3. Ventricular systole

4. Atrial diastole

During Atrial Systole / Ventricular Diastole the valves are _______________

• Both atrium contract and push blood to the ventricles through the A-V valves (tricuspid/bicuspid)

• A-V valves open

• Semilunar valves closed

During Ventricular Systole / Atrial Diastole the valves are ___________

• Both ventricles contract and push the blood through the semilunar valves to the Aorta and Pulmonary Artery.

• A-V valves closed

• Semilunar valves open

Lubb

• Ventricular systole

• A-V valves (tricuspid and bicuspid) are closing

Dubb

• Ventricular diastole

• Semilunal valves (pulmonary and aortic) are closing

How to find the Valves image

Cardiac Conduction System

Areas of the heart which initiate and distribute impulses throughout the heart which lead to a cardiac cycle (heartbeat)