Lesson Ten Flashcards
Left and right atria are…
Collecting chambers
Right atria function
Collects blood from Vena cava
Left atria function
Collects blood from pulmonary veins
Left and right ventricle function
Pumps
Right ventricle
Sends blood to the lungs via pulmonary trunk
Left ventricles
Send blood to the body via aorta
Atrioventricular valves
Valves between the atria and ventricles to prevent backflow of blood. Right side tricuspid
Left side bicuspid
Chordae Tendineae
Strong fibrous strings that support the AV valve, keeps valves from inverting with force of blood flow
Semi-lunar valves
Between ventricles and arteries exiting heart; prevents backflow of blood from pulmonary trunk into right ventricle. Prevents backflow of blood from aorta into left ventricle
Pulmonary trunk
Branches off the pulmonary arteries, received blood from right ventricle
Septum
Wall of the heart, separates left and right sides of the heart
Systole
Contraction of heart
Diastole
Relaxation of heart
Ventricles have a _____ contraction?
Stronger and longer
Luv-dubb sound of the heart is due to what?
Closing of the atripventricular valve and then the semi-lunar
Intrinsic quality of the heart
Can beat without any nervous system stimulation, meaning it can be removed from body and still beat
The best is controlled by…
Nodal tissue which has both muscular and nervous tissue characteristics
SA Node
Sinoatrial Node: found in upper wall of right atrium
AV Node
Atriocentricular node: found at bottom right atrium near the septum
How the heart beeps…
SA Node sends out excitation impulse every 0.85 seconds. The impulse causes both atria to contract, and then the impulses are sent to the AV Node. Then an impulse is sent from the AV Node and up the pukinje divers which stimulates both ventricles to contract from bottom upwards
Graph name
PQRST
P curve
Records stimulations contraction of atria as they drive blood out of their ventricles
QRS
Contraction of ventricles as they drive blood out of their arteries, must stronger contraction from ventricles
T
Marks recovery of ventricles
Heart rate center is located in the….
Medulla oblongata of the brain, SA Node is connected to brain by Vagus nerve
Vague nerve has two systems that affect heart beat:
Parasympathetic system causes the heart beat to slow down
Sympathetic system causes the heart beat to increase during time of stress
When the brain perceived the blood is delivered to tissues too slow….
The brain signals the SA Node to speed up its contraction
Systolic pressure
Refers to the pressure when the ventricles contract (highest blood pressure reading)
Diastole
Refers to the blood pressure when the heart is at rest (lowest blood pressure)
Pulse
As blood is pumped through arteries the walls swell and recoil
Normal blood pressure
120/80
Hypertension
High blood pressure
140/90 or 125/90
Reasons for high blood pressure
Stress Plaques High salt intake Smoking Stimulants Lack of excercise Diet Working too hard
Hypotension
Low blood pressure, blood does not reach all organs example 110/70
Reasons for low blood pressure
Cuts or amputated limbs, drugs, hormones
Body can adjust blood pressure by…
Being monitored by the hypothalamus, and the body can dilate thus lowering blood pressure in them or constrict to increase blood pressure
