Cardiovascular System Flashcards
What is the function of the cardiovascular system?
- Delivery oxygen and nutrients to cells and tissues
2. Remove carbon dioxide from cells and tissues
What is the pericardium?
It is the membrane that encloses the heart.
What makes up the pericardium?
- Fibrous pericardium
- Serous membrane made out of parietal and visceral pericardium
- Serous fluid
What are the three layers of the heart?
- Epicardium
- Myocardium
- Endocardium
What are the four chambers of the heart?
- Right and left atrium
2. Right and left ventricle
What separates the atrium and ventricles?
- Interventicular septum
2. Interatrial septum
What are the two atrioventricular valves?
- Bicuspid (mitral) valve - left side
2. Tricupid valve - right side
What are the two semilunar valves?
- Pulmonary semilunar valve
2. Aortic semilunar valve
When do the AV valves open and close?
- Open when heart is relaxed
2. Closed during ventricular contraction
When do the semilunar valves open and close?
- Closed when heart is relaxed
2. Opened during ventricular contraction
What are coronary arteries and what do they do?
They branch off the aorta to supply the heart muscle with oxygenated blood
What do the cardiac veins do?
They drain the myocardium of blood.
What is the sinoatrial (SA) node?
It is the heart’s pacemaker, enforces contraction of the heart at 75 bpm.
What is systole?
It is the contraction of the heart.
What is diastole?
It is the relaxation of the heart.
What is cardiac output (CO)?
It is the amount of blood pumped from each side (ventricle) of the heart in one minute.
What is stroke volume (SV)?
It is the amount of blood pumped by each ventricle in one contraction.
What is the normal heart rate of an adult?
75 BPM
How do we calculate cardiac output (CO)?
Heart rate (HR) * stroke volume (SV)
What factors can modify one’s heart rate?
- Neural (ANS) controls - Sympathic and parasymphatic nervous systems
- Hormones and ions
- Physical factors (temperature etc.)
What is the function of the vascular system?
Transports blood to the tissues and back to the heart.
What do arteries and arterioles do?
They carry blood away from the heart.
What do capillary beds do?
They play a role in the exchange between tissues and blood.
What do venules and veins do?
They return blood towards the heart.
What is the tunica media?
It is smooth muscle and elastic tissue in blood vessels.
What is microcirculation?
It is the blood flow through the capillary bed.
What are the various factors that can affect blood pressure?
- Neural factors / autonomic nervous system
- Renal factors
- Temperature
- Heat = Vasodilate
- Cold = Vasoconstrict - Chemicals
- Diet
Name the 4 routes substances take during exchange between tissues and blood.
- Direct diffusion through membranes
- Diffusion through inter cellular clefts
- Diffusion through pores of fenestrated capillaries
- Transport via vesicles
What forces fluid in and out of capillaries? (pressure)
- Blood pressure moves fluid and solutes out of capillaries
2. Osmotic pressure moves fluid into capillaries
What are some age-related problems related to the Cardiovascular System?
- Weakening of venous valves
- Varicose veins
- Progressive arteriosclerosis
- Hypertension
- From loss of vessel elasticity - Coronary artery disease
What is Atherosclerosis?
Build-up of plaque in blood vessels.
What can you do to reverse the atherosclerotic process?
- Good diet
- Stop smoking
- Exercise
Describe the blood flow through the heart.
Oxygen poor blood:
- Deoxygenated blood passes through superior & inferior vena cava into the right atrium
- Blood passes through the tricuspid valve into the right ventricle
- Tricuspid valve closes and the right ventricle contracts
- Blood is pushed through the pulmanory valve into the pulmonary arteries
- Blood moves into the lungs where it goes through gas exchange and is now oxygen rich
Oxygenated blood:
- Oxygenated blood flows into the left atrium through pulmonary veins
- Left atrium contracts, opening the bicuspid valve
- Blood flows into the left ventricle
- Left ventricle contracts, opening the aortic valve
- Blood flows through the aortic valve into the aorta and to the rest of the body
