Bio Quiz Flashcards
Blood vessels
Serve as passage ways for the blood
Myocardium
Made of cardiac muscle
Atria
The upper chambers of the heart
Pacemaker
A structure that begins the heartbeat that’s located in the right atrium
Veins
- Carry waste rich blood to the heart
- transport blood at a lower pressure
- Are necessary to allow blood to flow against the force of gravity
- Have the same 3 layers as arteries but not as strong
Valves
Prevent blood from flowing backward through the heart
- located between the upper and lower chambers of the heart
Ventricles
Lower chambers of the heart
Capillaries
- Thin walled blood vessels
- Are one epithelial thick
- Are so think that blood cells can only pass through them in a single file
- When your body and blood temp rise, the blood delivers the heat to the capillaries which then releases it to the tissue
2 major circulatory pathways in the body:
Pulmonary and systemic circulation
Pulmonary circulation
- Begins at the right ventricle and ends at the left atrium
- carries blood between the heart and lungs
- adds oxygen and removes carbon dioxide from the blood
Systemic circulation
- begins at the left ventricle and ends at the right atrium
- arteries of this system carry blood between the heart and the rest of the body
Coronary circulation
Supplies blood to muscles of the heart
Hepatic portal circulation
Carries blood from the digestive tract to the liver
Renal circulation
Carries blood to and from the kidneys
Right atrium
Receives deoxygenated blood from the head and the body via the superior and inferior vena cava
Left atrium
Receives oxygenated blood from the lungs
Right ventricle
Pumps blood to the lungs
Left ventricle
Pumps blood from the left atrium to the aorta
Bicuspid valve
- Permits blood to flow one way from the left atrium to the left ventricle
- located between the left atrium and left ventricle
- has 2 flaps
Tricuspid valve
- Keeps blood from coming back through the atrium
- located between the right atrium and right ventricle
- is composed of 3 leaflets
Semilunar valves
- The flaps of the valves open and close to allow the undirectional flow of blood out of the heart while preventing backflow
- 2 valve structures that sit between the right ventricle and pulmonary artery and between the left ventricle and aorta
- consists of a set of 3 crescent shaped flaps of tissue
Aorta
- arises from the left ventricle
- heart pumps blood through the aorta and branches into many smaller arteries so that each region of the body has its own system of arteries supplying it with fresh blood
Pulmonary artery
Carries deoxygenated blood to the lungs
Superior Vena cava
A large vein that returns blood to the heart from the head, neck, and both upper limbs
Inferior vena cava
Returns blood to the heart from the lower part of the body
Coronary arteries
Supply blood to the heart muscle and wrap around the outside of the heart
Papillary muscles
A small muscle within the heart that anchors the heart valves
Chordae tendae
Hold the atrioventricular valves in place while the heart is pumping
3 types of systemic branches
- Coronary circulation
- Hepatic portal circulation
- Renal circulation
Arteries
- Carry blood away from the heart
- 3 layers
- an outer layer of connective tissue
- a middle layer of smooth muscle that is very elastic and strong
- an endothelium made up of very smooth epithelial cells which allow blood to flow smoothly through the artery
Why do people feel dizzy when they stand up?
Cuz the blood is having a hard time climbing up. And fainting is your brains natural request for more oxygen rich blood. And when you faint and fall down, your head is the same level as your heart so it’s easier for the blood to reach the brain
Arteriole
One of the small terminal branches of an artery and connects with a capillary
Venule
A small vein that joins capillaries to larger veins
Diastole
- period of relaxation of the ventricles
- AV valves are tricuspid and bicuspid
- blood flows from the atria to the ventricles and by the end of diastole, the ventricles are 70% full
- diastolic pressure is the lowest pressure before the ventricles contract
Systole
- period of contraction of the ventricles
- the atria contracts forcing more blood into the ventricles completely filling them
- ventricles than contract
- pressure against the AV valves force then shut and opens the semi lunar valves
- blood flows into the pulmonary artery and aorta
- systemic pressure is the MAX pressure during ventricular contraction
SA node
A bundle of specialized muscle tissue that stimulates the myocardial cells in the atria to contract and relax rhythmically
AV node
Transmits the signal from the SA node through a bundle of fibres called the bundle of His
Purkinjie fibres
Are responsible for initiating the contraction of muscle cells in the right and left ventricles
Bundle of His
A bundle of branches
4 causes of high blood pressure
- obesity
- heredity
- smoking
- lack of exercise
Health problems of high blood pressure
The heart muscle can weaken which may lead to leaks in arteries
Low blood pressure health problems
Slows down the rate of the heart at which blood flows through the body. And parts that are far away from the heart that don’t receive enough blood can result in a chilling or injury of these parts
