Circulatory System Flashcards
Parts of the circulatory system
Heart
Blood
Blood vessels
Functions of the circulatory system
Transport O2 to cells for respiration Transport waste - CO2 out and other to kidneys Carry nutrients to body cells Carry WBC, antibodies to infection sites Seals wounds by clotting Regulates body temp Regulates pH Carried hormones from gland to target
How does blood regulate the body temperature?
Moves heat generated by internal cells to the surface where it can be released. Also manages body temp in cold weather conditions.
Types of circulatory system
Closed circulatory system
Open circulatory system
Closed circulatory system
Blood is contained in the blood vessels and is separated from the fluid that bathes cells.
Interstitial fluid
Fluid that bathes blood cells
Closed circulatory system example
Humans, all mammals
Open circulatory system
Cells are bathed in blood. Blood is pumped in body.
More primitive.
Example of open circulatory system
snails
Insects
Parts of the blood
Platelets
RBC
WBC
Plasma
Vasodilation
The widening of the blood cells
Vasoconstriction
The narrowing of the blood vessels
Percentage of blood that is plasma
55%
What is plasma?
Clear, slightly yellow liquid in blood. Is 92% water and contains dissolved glucose, vitamins, minerals, and proteins
Scientific name for red blood cells
Erythrocytes
What percentage of blood is rbc?
44%
Specialty of red blood cells
Specialized for transport of oxygen
Shape of red blood cells
Biconcave disk
How many red blood cells are in humans?
Males: 5.5 million/mL blood
Females: 4.5 million/mL blood
What blood cells have a nucleus?
White blood cells
Life span of red blood cells
90-120 days
Where are red blood cells produced?
Bone marrow
Hemoglobin
An iron-containing molecule that binds with oxygen and fits 280 million molecules in a single cell. Has 4 iron molecules and 1 globin
Why does a red blood cell lose its nucleus?
It loses when it enters the bloodstream in order to carry more hemoglobin
Scientific name for WBC
Leucocytes
How long does a wbc live?
3-4 days
Ratio of rbc to wbc
770:1
Purpose of wbc
Used for defense
Two types of leukocyte
Granular and non granular
Percent of leukocyte that are granular
70%
Percent of leukocyte that are non granular
30%
Characteristics of Granular leucocytes
Have multi lobed nuclei
Types of granular leucocytes
Neutrophils
Eosinophils
Basophils
Neutrophils
Phagocytic and ingest bacteria
Have 3 or more lobes in the nucleus
Eosinophils
Active in response to infections and allergies
Two lobes in the nucleus
Basophils
Prevent clotting
Nucleus is sometimes obscured by large granules
Types of non granular leucocytes
Lymphocytes
Monocytes
Lymphocytes
Recognize and remember specific pathogen to fend off if attacks again
Has large, oval shaped nucleus
Monocytes
Phagocytic and engulf foreign substances
Have c-shaped nucleus
What does an elevated wbc indicate?
Infection. Count could increase to double normal count.
Scientific name of platelets
Thrombocytes
Platelets
Non-nucleated cell fragments important to blood clotting
Size of platelets
1/3 size of red blood cell
Pulmonary circulation
The path that blood follows from the heart to the lungs and back to the heart
Systematic circulation
The path that blood follows from the heart to the body and back to the heart
Cardiac circulation
Movement of blood through heart tissues
Path of blood through blood vessels
Arteries - arterioles - capillaries - venules - veins
Function of arteries
Carry blood away from heart
Function of veins
Return blood to the heart
Characteristics of artery walls
Elastic and expand as waves of blood surge through during ventricle contraction and then snap back during relaxation of ventricles. Keep blood flowing in right direction and provides additional pumping motion
Thick and muscular.
Type of blood carried by arteries
Oxygenated except for the pulmonary artery
Wall layers in arteries and veins
Tunica adventita
Tunica media
Tunica intima
Lumen
Lumen size differences in vessels
Largest in veins, smaller in arteries, cells flow sing file in capillaries
Another name for lumen
Endothelium
Function of lumen
Where blood flows through
Function of valves
Prevent back flow and control blood flow
What controls blood flow in arteries
Heart contractions and artery muscles
Differences in pressure in blood vessels
Highest in arteries, lower in veins, lowest in capillaries
Differences in rage of blood Flow in blood vessels
Fastest in arteries, slower in veins, slowest in capillaries
What blood vessel does blood leak out from?
Capillaries
What blood vessel has valves?
Veins
Type of blood carried by veins
Deoxygenated except for pulmonary vein
Wall differences between blood vessels
Thick and muscular in arteries, thin in veins, one cell thick in capillaries
What controls blood flow in veins
Valves and skeletal muscle
What do capillaries join?
Venules and arterioles
Function of capillaries
Site where gases, nutrients, other materials are transferred between blood and tissue cells
Where are capillaries located?
Spread throughout body in fine network
Average diameter of capillaries
8micrometers
What controls blood flow in capillaries
Tiny sphincters
Blood vessels with no muscle in the walls
Capillaries
What occurs in step 1 of blood clotting?
Chemicals are realeased that activate platelets and attract them to injury. These platelets attract more. Platelet plug forms. BLood vessels vasoconstrict and reduce blood flow to that area.
What occurs in step 2 of blood clotting?
The clotting factor prothrombin (plasma protein, gluestick with cap on), is activated, which in turn activates fibrin(sticky web that seals wound and traps RBC and WBC).
What occurs in step 3 of blood clotting?
The wound is sealed. New cells form via mitosis. After the wound is repaired , clot dissolves.
How many steps are there to blood clotting?
3
Scab
Dead cells
Universal blood donor
O neg
Universal blood recipient
AB +
What happens if incompatible blood types are mixed?
The antibodies will attack the foreign RBC and cause clumping.
Agglutination
Clumping of blood
Deoxygenated blood
Low O2, high CO2
Oxygenated blood
Low CO2, high O2
Function of coronary blood vessles
Supply the heart with oxygen and nutrients.
Aorta
Largest artery in the body. Transport blood from heart to rest of body.
Superior Vena Cava
A vein that transports blood from the upper body to the heart.
Inferior Vena Cava
A vein that transports blood from the lower body back to the heart.
Pulmonary Artery
Transports blood from the heart to the lungs
Pulmonary Vein
Transports blood from the lungs to the heart.
Right atrium
Recieves deO2 from superior and inferior vena cava
Left atrium
Recieves O2 from pulmonary veins
Right ventricle
ships deO2 blood to lungs.
Left ventricle
Ships O2 blood to the body
Pericardiac sac and fluid
surrounds heart, reduces friction and protects against infection.
Humans have ______ circulation
Double (Heart pumps through 2 systems - systematic, pulmonary)
Heart beats approximately __ times/minute and _____ L fluid/day
70
10000
Atrioventricular valves
Tricuspid valve
Bicuspid valve
Semilunar valves
Pulmonary valve
Aortic valve
Tricuspid valve
Consists of 3 flaps of tissue, and has tendons that act like springs. In between R. atrium and R. ventricle.
Bicuspid valve
Consists of 2 flaps of tissue and has tendons.
Pulmonary semi-lunar
Located in pulmonary aorta
Aortic semi-lunar
Located in aorta
Semi-lunar valves
Pulmonary valve
Aortic valve
What causes lub sound?
Closing of atrioventricular valves
What causes dub sound?
Closing of semi-lunar valves
What causes a heart murmer?
When a valve leaks and allows backflow of blood.
Systole (systolic)
Contractile phase of heart - 0.3 seconds
Diastole (diastolic)
Relaxation phase of heart - 0.6 seconds
Heart muscles are _____ or self-excitatory
Myogenic
The heart sends out an ______ signal
electrical
SA node
Sino Atrial node. The pacemaker of electrical signal, consists of specialized cells.
Sequence of contraction
SA node sends out electrical signal, which moves to AV node and spreads across both atria, causing both atria to contract simultaneously. AV node sneds impulse to Bundle of His, which sends impulse to Purkinje fibres, causing both ventricles to contract and force blood out of heart into aorta or pulmonary arteries. Impulse travels back to the SA node and cycle repeats.
AV node
Atrio ventricular node
Bundle of His
Nerve cells in heart, recieve impulse from AV node and send to Purkinje fibres
Purkinje fibres
Nerve cells in heart, recieve impulse from Bundle of His and causes ventricles to contract.
ECG
Electrocardiogram, which records the electrical impulses from heart.
PQRST
Impulses from heart as shown on electrocardiogram
P
Atria contract
QRS
Ventricles contract
T
Ventricles relax
ECG determines problems with ____
Heart contraction
Heart Contraction Problems
Ventricular Fibrillation
Flat Line
Atrial Fibrillation
Ventricular Fibrillation
Caused by a wave of constant contraction that doesn’t stop to allow the heart to refill with blood - the heart just jiggles
Flat line
The heart has no rhythm
Atrial Fibrillation
Abnormal heart rhythm with rapid and irregular beating. Common in 2-3% of population, have regular brief episodes
Blood pressure
Force of blood on artery walls. Stated as a fraction
Hypertension
High blood pressure. Consistently 140/90mmHg and above
Hypotension
Low blood pressure. 90/60mmHg and below
White coat hypertension
High blood pressure only at doctor’s office.
Sphygmomanometer
Measures blood pressure
Factors that affect blood pressure
- Cardiac output (Increase in CO = Up in BP, increase CO by HR or stroke volume)
- Arteriolan Resistance (Up in diameter of artery walls = down in BP)
- Runniness of blood (Thinner blood = lower BP, people with high BP take blood thinners)
- Elasticity of vessel walls (more stretch = lower pressure)
Age (BP increases with age)
Activities to Lower BP
Regular Exercise, Helathy diet, no smoking, limit alcohol + caffeine, reduce stress, mdication
Posture during BP test
Calmly seated for 5 mins, back well supported, arm relaxed at heart level, legs uncrossed, feet flat on floor
For an Accurate BP reading
No caffeine, smoking, exercise for 30 mins, comfortable bladder, no talking
Vasodilators
Chemicals which expand/open the blood vessel lumen
examples of Vasodilators
Alcohol, nicotine, nitroglycerin
Result of vasodilators
Increase in blood flow, heat loss, heart activity
Decrease in BP
Vasoconstrictors
Chemicals which decrease diameter of blood vessels
Examples of vasoconstrictors
Caffeine, cold medications
Result of vasoconstrictors
Decrease in blood flow, heart activity
Increase in blood pressure
Lymphatic System
A system that runs parallel to the circulatory system and drains the fluid left in organs.
What composes the lymphatic system?
Organs, vessels, and a fluid called lymph (similar to interstital fluid)
Lymph capillaries
Closed ended tubes found in spaces between cells throughout body. Combine to form lymphatic vessels and rejoin circulatory system near heart.
Lymph nodes
All fluid passes through at least 1 lymph node, which are bean shaped organs up to 1 inch long that supply lymphocytes to bloodstream and remove foreign cells
How does metastasis through lymphatic system work?
Cancer cells travel through lymphatic system and secondary location can be predicted by direction of lymphatic flow from primary site.
Other parts of the lymphatic system
- Thymus Gland
- Spleen
- Tonsils
Aneurysm
Weakened artery wall where blood collects and pressure builds, forming bulge
Risk of bursting and person can bleed out
Embolism
Blood clot that has formed and travelled to another place in body
Clot could lodge in smaller arteries and block blood flow
Thrombosis
Blood clot forms in veins
Often in deep leg veins and is not as common in arteries
Could break off and become an embolism
Varicose vein
Occurs when valves in veins do not close properly and blood can backflow
Pooling in veins makes them swollen and twisted
Atherosclerosis
Fatty deposits build up in artery walls and cause the walls to narrow
This causes narrowing of blood vessel which causes decrease in blood flow, increase in blood pressure, and can eventually stop blood flow
Arteriosclerosis
General term for several conditions in which the walls of arteries thicken and lose elasticity. Common type is atherosclerosis
Angioplasty
A surgical procedure used to open up a clogged artery; treat arteriosclerosis
Tube is inserted into artery, at clogged site a balloon inflates and forced artery open
Stent
Permanent wire mesh tube inserted during an angioplasty
Coronary bypass
Surgical procedure where blood flow is rerouted around blocked arteries
Healthy artery from another body part is taken and used for new pathway
Angina
Heart pain that can be caused by arteriosclerosis
Stenosis
Narrowing in opening of the heart valves or arteries
Regurgitation
Heart valve does not close completely and blood flows backward instead of forward through the valve
Heart valve diseases
Stenosis
Regurgitation
Mitral valve prolapse
Arrhythmia
An irregularity in speed of rhythm of heartbeat
Pacemaker
A device that sends electrical impulses that control the rate of the heartbeat
Congenital heart defect
Heart defect present from birth
Common defect is a murmer
Heart murmur
Valve does not open or close properly
Types of stroke
Ischemic stroke
Hemorrhagic stroke
Ischemic stroke
Stroke caused by a clot in a blood vessel, blocking blood flow to the brain
Hemorrhagic stroke
A strike caused by the bursting of a blood vessel in the brain, which causes blood to leak into the surrounding brain tissue
Hemophilia
Inherited disorder in which the blood does not clot normally
Leukaemia
Cancer of the white blood cells
Two types of leukemia
Myeloid
Lymphoid
Myeloid leukemia
Characterized by prescience of too many leucocytes that are immature, unable to fight infection, and crowd out red blood cells.
Lymphoid leukemia
Cancer of lymphocytes, but is very similar to myeloid leukemia
Acute vs chronic leukemia
Acute appears suddenly with fast death, chronic can go undetected for months or years
Heart attack
Flow of blood to heart is stopped (ex by a clot) and heart no longer receives oxygen
Pericarditis
Swelling and inflammation of pericardium. Usually acute and improves on own.
Cardiomyopathy
Heart muscle disease. Any disease that affects the heart muscle.
Heart failure
Heart is no longer strong enough to pump blood efficiently. Caused by heart attacks or other disorders and can cause fluid buildup in lungs