Circulatory and Immune Systems Flashcards
(105 cards)
1
Q
What is the circulatory system?
A
One-way system of vessels that transport blood and the cells and substances suspended and dissolved in blood throughout the body
2
Q
What are the three main functions of the circulatory system?
A
- transport gases, nutrients, waste material
- regulates internal temperature to maintain homeostasis
- protects the body from invasion of pathogens
3
Q
What are the three main components of the circulatory system?
A
Heart- the pump
Blood- the trnasport medium
Blood vessels- the passageways
4
Q
What are the three main types of blood vessels?
A
- arteries
- veins
- capillaries
5
Q
What is the hierarchy of blood vessels?
A
veins, venules, capillaries, arterioles, arteries
6
Q
What do arteries do?
A
Usually carry oxyge-rich blood away from the heart (pulmonary artery carries deoxygenated blood)
7
Q
What do arteries look like?
A
- have thick elastic walls
- allows walls to expand and contract with the contration of ventricles (this and the pressure keeps blood flowing in the right direction)
8
Q
What do veins do?
A
Usually carry deoxygenatred blood toward the heart (pulmonary vein carries oxygenated)
9
Q
What do veins look like?
A
- have thinner, non-elastic walls than arteries and a larger inner circumferene
- cannot contract
- contraction of muscles keep blood moving toward heart
- one way valve also prevents blood flowing backwards
10
Q
What are capillaries?
A
Tiny vessels separating arteries and veins where nutrients, gases, etc are transferred to cells and waste material move material move into the blood
11
Q
What do capillaries look like?
A
- smallest of blood vessels; spread through the body in a fine network (about 8um; the size that the largest blood vessel can move in a single file line)
- the capillary wall is one cell layer thick for diffusion to occur
- blood flow through capillaries is slower than any other part of the circulatory system (diffusion can occur)
- cells of the body are constantly covered in extracellular fluid (ECF); all material exchanged between capillaries and cells must pass through it
- only 5-10% of capillaries have blood in them at any time
12
Q
What is vasodilation?
A
Increase blood flow near the skin, helping the body to release heat and decrease blood pressure
13
Q
What is vasoconstriction?
A
Decrease blood flow near the skin, which helps to conserve body heat and increase blood pressure
14
Q
What do vasodilation adn vasoconstriction allow?
A
Allows the body to maintain temp of 37 degree celsius and homeostasis (homeostatic regulation)
15
Q
What is the heart?
A
A muscular organ that is located slightly to the left of the middle of your chest and roughly the size of two fists
16
Q
What are the three main functions of the heart?
A
- pumping blood throughout the body
- ensuring blood flow only moves in one direction
- separating oxygen rich blood from oxygen poor blood
17
Q
What is the heart made of?
A
- made up of cardiac muscle, which contract rhythmical and involuntarily
- muscle cells relax completely in brief milliseconds between contractions to prevent fatigue
18
Q
How many chambers are in the heart?
A
mammalian and bird hearts have four chambers
19
Q
What are atria?
A
Two top chambers that fill with blood returning to the heart
20
Q
What are ventricles?
A
Two bottom chambers that recieve blood from the atria and pup it away from the heart
21
Q
What is the septum?
A
Thick muscular wall separating atria and ventricles
22
Q
What are the four valves that ensure blood flows right?
A
atrioventrical valves- separate atria and ventricles
include:
tricuspid valvue- valve on the right made of three flaps
bicuspid valve- valve on the left made of two flaps
pulmonary semilunar valve- valve separating the ventricles from the pulmonary arteries
aortic smilunar valve- valve separating ventricle from the aorta
23
Q
What are the steps of blood circulation in the heart?
A
- oxygen poor blood goes through the superior/inferior vena cava into the right atrium
- blood moves from the right atrium through the tricuspid valve into the right ventricle
- from the right ventricle it goes through the pulmonary valve and is pumped away from the heart to the lungs for gas exchange
- oxygen rich blood from lungs moves through pulmonary veins to teh left atrium
- blood moves from left atrium through the bicuspid valve to the left ventricle
- from the left ventricle it moves through the aortic valve and gets pumped away from the heart through the aorta and to the rest of the body
24
Q
What are the two main branches of the circulatory system?
A
Pulmonary- transports blood to alveoli in the lungs for oxygenation and CO2 removal (via right ventricle)
Systematic- delivers nutrients to and removes waste from cells throughout the body (via left ventricle)
25
What is the technical third branch of the circulatory system?
coronary pathway- dedicated to provide blood to cardiac muscle tissue (via coronary arteries)
26
How are heart beats controlled?
- rate/strength of the heartbeat is under the control of teh nervis system and is triggered by electrical signals from the heart iself
27
What is the sinoatrial (SA) node?
Bundle of specialized muscle tissues that stimulate the muscle cells in the atria to contract/relax rhythmically (also called the pacemaker)
28
What is the process of controlling the heartbeat?
- SA node generates electrical signals that spreads over two atria and makes them contract simultaneously
- the atria contract, signal reaches the atrioventricular (AV) nodes
- AV nod transmits signal through the atrioventricuylar bundle/bundle of His
- these fibres relay the signal to the purkinje fibers, which initiates the simultanous contraction of the ventricles
29
What are electrocardiographs?
Map the electrical impulses of teh heart by recording the electrical activity of the heart as it contracts and relaxes
30
Process of electrocardiograph?
- electrodes are placed on the body surface and record electrical impulses
- impulses are displayed on the electrocardiogram
- doctors analyze the graph for proper heart function
31
What is the "lub" and "dub" of teh lub dub sound of the heart?
lub- AV valves closing
dub- semilunar valves closing
32
What are heart murmurs?
- occur when valves (usually AV or bicuspid) don't close completely
- generally harmless, makes heart less efficient
- heart compensates by beating faster and eventually enlarging
33
What is blood pressure?
As blood passes through the vessels in the body it exerts pressure against the walls of blood vessels
34
What is systolic pressure?
The maximum pressure during ventricyular contraction
35
What is diastolic pressure?
The lowest pressure before ventricles contract again
36
What could change blood pressure?
- blood volume
- arterior resistance/size of blood vessel
- arteriolar elasticity
37
How is blodo pressure measured?
Measured as systolic over diastolic pressure (noraml pressure is roughly 120/80 mmHg)
38
What is hypertension?
High blood pressure
39
What is hyper tension caused by?
- inactive lifestyle
- stress
-obesity
- age
- alcohol use
- race
- sodium intake
- genetics
40
What does hyder tension cause?
- causes heart to work harder to pump blood (make heart enlarged and weaken)
- increases force on blood vessels (make them wekan and increase the risk of stroke or heart attack)
- can lead to heart attacks, strokes, kidney disease
41
What is stroke volume?
Amount of blood pumped with each beat of the heart (average 70mL)
42
What is heart rate?
Number of rimes heart beats per minute (average 60-100)
43
What is cardiac output?
Amount of blood that flows (average 4900mL/min)
44
How id cardiac output calculated?
Heart Rate * Stroke volume = cardiac output
45
What is arteriosclerosis?
General term describing several conditions where artery walls thick and lose elasticity (become harder)
46
What is atherosclerosis?
Condition where plaque builds up on the inside of the artery walls (blood flow is decreased, blood pressure increases)
47
What can atherosclerosis lead to?
- may lead to agina (chest pain), blood clots, shortness of breath, heart attack, heart failure
48
What are treatments of atherosclerosis?
Aspirin- prevents clots from forming at all
"clot busting" medicine- like vrokinase or T-PA; can break down existing clots
Angioplasty- involves inserting a tube into a clogged artery
49
What happens if a coronary artery is blocked?
A coronary bypass may be needed (segment of healthy artery or vein is taken from elsewhere and used to make a path around the blockage)
50
What are the components of blood?
55% plasma
1% buffy coat (leukocytes and platelets)
45% Erythrocytes (RBC)
51
What is plasma?
The fluid portion of the blood
52
What does plasma contain?
- blood proteins (fibrinogen, albumins, globulins)
- other organic substances (urea)
- inorganic ions (calcium, chlorine, magnesium, potassium, sodium, bicarbonate, carbonates, phosphates)
53
What are red blood cells?
Erythrocytes; specialized for oxygen transport
also take CO2 away from cells and back to the lungs
54
What is the red blood cell made up of?
- no nucleus
- 280 million iron-containing hemoglobin molecules (which cehmnically binds with oxygen and releases it by diffusion to cells that need it)
- has a biconcave shape to increase the surface area for oxygen bindng
55
Where are red blodo cells produced?
Produced in the bone marrow (and last about 120 days)
- change shape after losing the oxygen molecules, making them reflect "blue" light (color of deoxygenated blood in the veins)
56
What are white blodo cells?
Leukocytes; part of the body's response to infection
- has a nucleus
57
What are the three groups of WBC/Leukocytes?
- granulocytes
- mono cytes
- lymphocytes
58
What do granulocytes and monocytes do?
Engulf and destory foreign particles/pathogens
59
What do granulates consist of?
Neutrophils, basophils, eosinophils
60
What do monocytes become?
can leave the bloodstream and become further specialized as macrophages, which destroy bacteria
61
What do lymnphocytes do?
Produce antibodies that incapacitate pathogens and allow them to be easily detected and destroyed. Consist of B cells and T cells
62
What are platelets?
Platelets are fragments of cells that form when larger cells in the bone marrow break apart
- no nuclei
- have a key role in blood clotting
63
What is the process of blood clots?
- Injured blood vessels release a chemical messengers to attract platelets to the site
- The platelets rupture and combine with other blood components to produce an enzyme called thromboplastin
- As long as calcium ions are present, thromboplastin will react with prothrombin to produce thrombin
- Thrombin reacts with fibrinogen (a protein) to produce fibrin
- Fibrin is an insoluble material that forms a mesh of strands around the injured area. This mesh traps escaping blood cells and forms the clot
64
What is hemophilia?
Hemophilia is the result of insufficient clotting proteins in the blood. Individuals with the severe form (less than 1% of the clotting protein in the blood) are in constant danger of bleeding to death
65
What is leukemia?
Cancer of white blood cells
66
What is myeloid leukemia?
characterized by the presence of too many leukocytes. These leukocytes are immature and unable to fight infection. They crowd out RBCs, which causes anemia and fatigue
67
What is Lymphoid leukemia?
affects lymphocytes, with very similar symptoms
68
What are treatments of leukemia?
- blood transfusions (increaase RBC and healthy WBC counts)
- chemotherapy
- bone marrow transplant (healthy WBC can grow)
69
What is sickle cell anemia?
Sickle Cell Anemia is a genetic disorder that causes an irregular shaped RBC (thus causing less oxygen to be carried throughout the body)
70
What is carbon monoxide poisioning?
Carbon monoxide poisoning occurs because hemoglobin has a higher binding affinity to CO than to O2. As a result, CO will bind to hemoglobin in place of oxygen. This means that the tissues of the body won’t receive enough O2 and a person can suffocate to death
71
What is altitude sickness?
Altitude Sickness occurs when there is less oxygen at higher elevations and the body requires more RBCs to compensate
72
What is the lynmphatic system?
network of vessels, glands, nodes that collect a fluid (lymph)
73
How is lymph formed?
- is formed in close ended tubes in capillary beds
- as blood circulates, some plasma escapes from capillaries and becomes apart of interstitial fluid which is collected by the pymphatic system and returned to the nervous system
74
What are lymph nodes?
glands found throughout the lymphatic system, which house lymphocytes as they mature
- also contain macrophages which trap and destroy bacteria circulating within the body
75
What are the three lines of defence against pathogens?
- physical defence
- non specific defence
- specific defence
76
What is physcial defence?
Nose, sinuses, tonsils, eyelids, tears, eyelashes, hair, ear wax, mucus membranes and stomach acid
77
What is non specific defence?
Known as cell-mediated immunity. This involves three types of WBCs - macrophages, neutrophils and monocytes
- also includes natural killer cells which target the body cells that have become cancerous or infected by viruses
78
What is cell mediated immunity/inflammatory response?
ncreased blood flow occurs. This results in swelling, warmth, redness, more clotting proteins and more WBCs
79
What do monocytes and macrophages do?
Ingest and destroy invading bacterial pathogens via phagocytosis
80
What do neutrophils do?
Neutrophils engulf microbes and then enzymes digest both the neutrophils and microbes producing pus
81
What are specific defenses?
Known as antibody-mediated immunity
82
What are antibodies?
Proteins that recognize foreign material and act to neutralize them
83
What are antigens?
Markers on the surface of msot cells and pathogens
84
What do antibodies and antigens provide?
provide an identification system telling your body what belongs to it and what is a ‘foreign’ material
85
What do specialized pymphocytes (B anbd T cells) have?
have antigen receptors to allow them to recognize foreign antigens
86
What do antibodies have?
Antibodies have the same shape as the antigen receptors, so they can bind with and neutralize the antigen
87
What are T cells/T lymphocytes?
- mature in teh thymus gland
- have four main groups
88
What are the four main groups of T Cells?
Helper T Cells: Identify invaders by their antigens and signals other lymphocytes
Killer T Cells: Destroy infected cells
Suppressor T Cells: Calm immune system to prevent own-cell digestion
Memory T Cells: Recognize foreign cells in the future
89
What are B cells/B lymphocytes?
- mature in the bone marrow
- have two main groups
90
What are the two groups of lymphocytes?
Plasma B Cells: They produce antibodies that bind to foreign antigens and identifies them for T cells
Memory B Cells: Remain in the blood to recognize antigens in the future
91
What is the process of formation of antibodies?
- Macrophages engulf the pathogens
- Foreign antigens are not destroyed, but rather protrude through the cell membrane of the macrophage
- Helper T cells bind to the antigens surface on the macrophage. This causes the release of chemical messengers from both cells, causing T cells to multiply
- Helper T cells signal B cell which
split into plasma B cells which
produce massive quantities of antibodies which can then “attack and disarm,” the invaders directly and memory B cells which remain in the blood, ready to trigger another immune response when necessary
- Helper T cells also activate killer T cells which will destroy the macrophages and the pathogens inside of them. They also destroy infected cells by puncturing a hole in their cell membrane
- Suppressor T cells inhibit the immune response after the “war” has been won on the pathogen so that normal tissue doesn’t get destroyed
- Some T cells do not respond to the invading pathogens the first time they are exposed to them. Instead, these memory T cell remain in the body to create antibodies more quickly next time the pathogen is encountered
92
How do vaccines work?
inject dead, synthetic or weakened pathogens into the blood so that memory B cells and antibodies can be developed
93
What are the antigens on red blood cells?
Glycoprotein markers
- A, B, or Rh factor
94
What are the different blood types?
- A and B markers independently (Type A or B)
- In combination (Type AB)
- neither (type O)
95
What dpes the rheus factor marker do?
If the rhesus factor marker is present (Rh+), you are considered to have a positive blood type
If you do not have this marker (Rh-), you are considered to have a negative blood type
96
What do incompatible blood types result in?
will lead to the body’s immune system attacking it. This leads to a condition known as agglutination, cause the blood cells to clump
97
WHat is HDN(hemolytic disease of the newborn)?
- occurs when a Rh- pregnant mother, has a first baby that is Rh+
- During delivery, blood comes into contact and the mother begins to produce Rh+ antibodies
- During a second pregnancy (of another Rh+ fetus), there is a chance that antibodies can cross the placenta and attack the fetus’ blood cells causing brain damage, deafness or death
- This can be prevented by injecting Rh- women with an antibody preparation against the Rh factors within 72 hours after the birth of an Rh+ child
98
What are immune disorders?
Autoimmune disorders are when T cells or antibodies attack the body’s own cells as if they were foreign antigens
99
What is rheumatoid arthritis?
Example of autoimmune disorder; characterized by the inflammation of the lining of the joints
- The immune response starts at the joints but can continue to attack cartilage, bone, tendons and ligaments
100
What are treatments for rheumatoid arthritis?
Aspirin, anti-inflammatory drugs, steroids
101
What are allergies?
Hypersensitivity or an allergy is an exaggerated response by the immune system to a harmless material, such as pollen, mould or animal dander.
102
What are the two types of allergic reactions?
- Acute/immediate reactions
- Delayed reactions
103
What are Acute/immediate reactions?
occur within seconds and disappear within 30 minutes.
The body releases histamines, makings blood vessels more permeable (area becomes red and swollen)
Specialized antibodies also trigger the release of cellular fluids, which result in watery eyes and a runny nose
104
What are delayed reactions?
set off by T cells, are slower but last for a longer time (i.e. cosmetic and/or jewelry allergies)
105
What are AIDS?
Acquired Immune Deficiency Syndrome; an immunodeficiency disease
The virus that causes the disease (human immunodeficiency virus - HIV) destroys helper T cells, causing the person to fall victim to diseases that the immune system would normally prevent
The disease spreads through exchange of bodily fluids either by sexual contact, blood-to-blood contact or via contaminated needles
