Circulatory System: Chapter 8 Flashcards
What are the 3 Main Functions of the Circulatory System?
1.) Transportation : such as oxygen and nutrients to cells, as well as removal of cellular waste
2.) Body Temperature : Regulation of our internal body temperature
3.)Protection : Against blood loss due ti injury and against infections
What is the fluid membrane that surrounds the heart?
Pericardium
What muscle does the heart have? Is it voluntary or involuntary
Cardiac Muscle which us involuntary
How many chambers does the heart have? Name all.
ATRIUM
1. Top Left chamber: Left atria
2. Top right chamber: Right atria
VENTRICLES
3. Bottom left chamber: left ventricle
4. bottom right chamber: right ventricle
What are the valves in the heart? What is the purpose? Where are they found?
Ensure that blood flows in the correct direction
ATRIOVENTRICULAR VALVES
These valves are found between the atria and the ventricles.
1. Right valve is called Tricuspid Valve : has 3 flaps
2. Left valve is called Bicuspid Valve (also known as mitral valve) : has 2 flaps
SEMILUNAR VALVES
1 found between ventricle and aorta, other 1 found between ventricle and pulmonary arteries
2 of them
What are arteries? Characteristics?
- Carry blood away from the heart.
- Has highly elastic walls to allow the artery to expand when blood surges through during contractions
What are veins?
- Veins carry blood towards the heart
- Thinner walls and larger inner circumference than arteries
- less pressure
What are Capillaries
-Join arteries and veins together
- transfer oxygen and nutrients to tissue cells
- one layer cell thick
- materials move into and out of the capillaries through facilitate diffusion
What causes or affect heart rates?
- Nervous Stimuli : fear, excitement
- Physical Stimuli : exercise, increase of CO2 in blood
- Chemical Stimuli : Nicotine, Caffeine, Alcohol
How does the Heart Beat?
1.) S.A. nodes stimulates the right and left atria ti contract
2.) nerve impulses reach the A.V. nodes then waits for ventricles to fill with blood
3.) A.V. nodes transmits nerve impulses to the ventricles via the bundle of His then Purkinje Fibres then ventricles contract.
What measures the electrical activity of the heart?
- Electrocardiogram (ECG/EKG)
- measures the electrical activity of the heart.
Explain the P, QRS, and T parts of a ECG (Electrocardiogram)
P : electrical activity before atria contracts
QRS : electrical activity before ventricles contract
T : Electrical activity as ventricles relax after contraction
What happens in a abnormal ECG? What is it called when it is too slow or too fast?
- Indicates arrhythmia which usually irregular heart beat/rhythm
- irregularly SLOW : bradycardia
- irregularly FAST : Tachycardia
What us Ventricular Fibrillation?
Uncoordinated twitching of the heart, can lead to coma or death
What is a Sphygmomanometer?
- measures blood pressure
What is systolic and diastolic in blood pressure?
Systolic : ventricles contract in MAX PRESSURE 120 mmHg
Diastolic : ventricles relax in MIN PRESSURE 80 mmHg
In heart sounds what does “Lub” and “Dub” indicate
- “Lub”
1. SA nodes send signals contraction of atria
2. Av valves closes - “Dub”
1. Sa nodes signals Av nodes for ventricles contraction
2. contraction happens
3. semilunar valves close to prevent backflow
What is Stroke Volume? Heart Rate? Cardio Output?
Stroke volume : the volume of blood for every pump/beat
Heart Rate : number of beats per minute
Cardio Output : volume if blood pumped every minute
What is the formula for Cardio Output?
Stroke Volume x Heart Rate
= Cardio Output
What is Arteriosclerosis?
A condition in which the walls of the arteries thicken and lose elasticity thus becoming hard
- blood flow is decreased