Human Anatomy- The Heart

Cardiovascular system

Blood, heart and blood vessles

Blood cirulation helps maintain what

homeostatis

What are the functions of the cardiovascular system

Transport, regulate, and protect

What happens if the heart fails to pump

Nutrients arent delivered, wastes arent removed, death occurs

Cardiac output

Amount of blood pumped per minute out of ½ of the heart

Arteries

Carry blood away from the heart

Veins

Carry blood back to the heart

Pulmonary circulation

R side of the heart to lungs back to the L side of the heart

Systemic circulation

L side of heart to all other tissues and then back to the R side of heart

Percardium

Covering of heart

Outer fibrous

Dense C.T. anchoring heart to surrounding tissue

Inner serous

double layer w/ serous fluid in between

Heart wall

Epicardium, myocardium, and endocardium

Epicardium

Continues w/ serous layer, outermost

Myocardium

Cardiac muscle tissue, middle

Endocardium

the thin, innermost layer of tissue that lines the chambers (atria and ventricles) and heart valves

Atria

R and L superior chambers

What does the Atria do

Receives blood from veins, pumps to ventricle

Where is the atria

Apex of the heart, where ventricles meet (“the corner”)

Heart valves

Dense C.T. flaps that prevent blood flow

Atria ventricular valves

Shut when ventricles contract

Atria ventricular valves include

Chardae tendinae and papilary muscles

Semilunar valves

Shut when ventricles relax

What is the “heart beat”

The valves closing

Where is the fibrous skeleton

Between Atria and Ventiuls

What does the fibrous skeleton do

Provide structural support and anchors valves

What is the fibrous skeleon an attachment point for

Cardiac muscle cells

Electrical insulatiar is between

Atria and ventricles

Coronary circulation

blood flow feeding heart tissue

Coronary arteries

Branch off of aorta

Coronary veins

demp into coronary sinus, connect to the right atrium

Circulation only occurs during

Ventricular relaxation

Cardiac muscle tissue is

Striated

Striated mean

Contains sarcomeres

What is the shape of cardiac muscle tissue

Short and branched

Cardiac muscle cells are connected via…

Intercalated discs

Intercalated discs carries

action potential/excitatory impulse from one cell to the next

If one cell contracts…

All connected cells will contract

Cardiac muscle tissue has many…

Mitochendria

Autorhythmicity

Can initiate its own heartbeat and rythm

SA node

Specialized cardiac muscle in R Atrium

SA node acts as a

Pacemaker, about 70-80 BPM

SA node creates what

Atrial Contraction

SA node stimulates

AV node at the bottom of R atria

AV node slightly delays what

Conduction to ventricles

AV node sends impulses where

Down AV bundle, then they split to R and L bundle, and Punkiage fibers

AV node holds

Rabid dispursement of impulse across ventricles

Innervation of the heart

Via ANS

Sympathetic

Increases heartbeat and increases force of contraction

Parasympathetic

Can only decrease heartbeat

Cardiac cycle consists of

Systole and diastole

Systole

Contraction of heart chamber

Diastole

Relaxation of chamber