Chapter 1 - Circulation & Immunity Flashcards
1
Q
What are the components of the circulatory system?
A
Heart, Blood Vessels, Blood
2
Q
What are the functions of the circulatory system?
A
- Transport - of gasses (from the respiratory system), nutrients (from the digestive system) and waste materials
- Regulation - of internal temperature
- Transportation - of hormones (reaction trggering chemicals produced by the endocrine system - example: estrogen, testosterone, adrenaline)
- Protection - against blood loss from injury and against disease causing microbes or toxic substances introduced into the body
3
Q
Amount of blood pumped by the heart is measured in what?
A
mL/minute
4
Q
What is cardiac output?
A
Cardiac output is the amount of blood pumped by the heart, measured in mL/minute
5
Q
What two factors affect cardiac output?
A
- Heart Rate - number of beats per minute
- Stroke Volume - amount of blood pushed out of the heart with each heartbeat
6
Q
What does “stroke volume” depend on?
A
- How easily the heart fills with blood; related to the volume of blood returning to the heart
- Distensibility (the stretchiness) - of the ventricles
- How readily the heart empties; related to the strength of ventricular contraction & pressure exerted by artery walls
7
Q
How is cardiac output calculated?
A
Cardiac Output = Stroke Volume x Heart Rate
eg. avg person stroke volume = 70ml and resting heart rate is approximately 70 beats per min, thus;
Cardiac Output = 70ml x 70 beats per min = 4900ml/min
8
Q
How much blood volume does the average person have in the body?
A
Average volume of blood a person has is 5 liters
9
Q
How often does the total volume of blood within the body, circulate through the heart?
A
Total volume of blood in the body circulates through the heart about - once per minute
10
Q
Name the functions of the heart
A
- Pumping - blood through the body
- Keeping oxygen RICH and oxygen POOR blood - separated
- Ensuring that blood ONLY FLOWS - in ONE directions through the body
11
Q
What type of muscle are the walls of the heart composed of?
A
Cardiac muscle - not found anywhere else within the body
12
Q
What makes contraction of cardiac muscle cells special?
A
Contraction of cardiac muscle is - rhythmic & involuntary
Cardiac muscle is - autorhythmic (it initiates it’s OWN contractions)
13
Q
Why do muscle cells of the heart relax between contractions?
A
To prevent fatigue
14
Q
How often does your heart need to beat per minute for your entire lifetime?
A
Approximately 70 beats per minute
15
Q
What does the heart require, in order to beat properly?
A
A reliable oxygen supply
16
Q
Through which vessel, does freshly oxygenated blood LEAVE the heart?
A
Through the aorta
17
Q
Name the arteries that supply the heart itself with blood?
A
Coronary arteries
18
Q
What do coronary arteries resemble?
A
A “crown” - wrapping around the heart
19
Q
What are the names of the veins/vessels, through which DEOXYGENATED blood flows back INTO the heart?
A
Superior vena cava
Inferior vena cava
20
Q
Which atrium receives the DEOXYGENATED blood?
A
Right atrium
21
Q
Where does blood flow, AFTER it leaves the right atrium?
A
Into the right ventricle
22
Q
Which artery takes DEOXYGENATED blood to the lungs?
A
Pulmonary artery - right and left sides
23
Q
How is OXYGEN RICH blood, returned to the heart from the lungs?
A
Via the - left & right pulmonary veins
24
Q
Which atrium receives OXYGEN RICH blood?
A
Left atrium
25
Where does blood flow, AFTER it leaves the left atrium?
Into the left ventricle
26
Which MAJOR vessel takes the freshly OXYGENATED blood from the heart to supply other parts of the body?
The aorta
27
What is the name of the "valve", located between the right atrium & right ventricle?
Right atrioventricular valve - AKA "Tricuspid valve"
28
What is the name of the "valve", located between the right ventricle & pulmonary artery?
Right semilunar valve - AKA "Pulmonary valve"
29
What is the name of the "valve", located between the left atrium & left ventricle?
Left atrioventricular valve - AKA "Bicuspid/Mitral Valve"
30
What is the name of the "valve", located between the left ventricle & aorta?
LEFT semilunar valve - AKA "Aortic Valve"
31
Describe the path of blood flow as it ENTERS the heart
Path of blood flow upon ENTERING the heart:
- DEOXYGENATED blood enters the heart thru the - superior & inferior vena cava
- DEOXYGENATED blood flows INTO the - right atrium
- The RIGHT atrioventricular valve (tricuspid valve) OPENS
- DEOXYGENATED blood flows FROM the right atrium THRU the right atrioventricular valve - INTO the right ventricle
- The RIGHT atrioventricular valve closes
- The RIGHT Semilunar valve (pulmonary valve) - OPENS
- DEOXYGENATED blood flows from the right ventricle THRU the RIGHT semilunar valve - INTO the pulmonary artery
- The pulmonary artery (left and and right) - takes the DEOXYGENATED blood towards the lungs to receive oxygen
- FRESHLY OXYGENATED blood returns TO the heart via - left & right pulmonary veins
- FROM the left & right pulmonary veins - FRESHLY OXYGENATED blood flows INTO - the left atrium
- The LEFT atrioventricular valve (bicuspid valve) - OPENS
- OXYGENATED blood flows FROM the left atrium THRU the left atrioventricular valve - INTO the left ventricle
- The LEFT atrioventricular valve closes
- The LEFT semilunar valve (aortic valve) - OPENS
- FRESHLY OXYGENATED blood flows FROM the left ventricle THRU the LEFT semilunar valve (aortic valve) to and THRU the aorta - to supply the body with oxygenated blood
32
What is diastole?
Diastole - phase of the heart's cycle, where a chamber of the heart (atrium or ventricle), RELAXES & FILLS with blood
33
What is systole?
Systole - phace of heart's cycle when the ventricles CONTRACT, to EJECT blood from within the chamber
34
What are the two sounds of the heart?
Dub & Lub
35
How is the "dub" sound of the heart made?
Dub sound - occurs when the semilunar valves are CLOSED
36
How is the "lub" sound of the heart made?
Lub sound - occurs when the atrioventricular (AV) valves are CLOSED
37
What occurs during ventricular systole (contraction)?
Ventricular systole (contraction) - the two ventricles CONTRACT & force blood OUT of the heart
THIS creates HIGH pressure - forcing the atrioventricular valves to CLOSE
Making the "lub" sound
And semilunar valves are forced OPEN by the high pressure of the blood leaving the ventricles
38
What occurs during atrial systole (contraction?
Atrial systole (contraction) - the atria (two atriums) CONTRACT & force blood OUT of the atria, INTO the ventricles
The atrioventricular valves are - OPEN during this time
The semilunar valves are - CLOSED
39
What occurs during atrial & ventricular diastole (relaxation)?
Atrial & ventricular diastole (relaxation) - the atria & ventricles RELAX & FILL with blood
Atrioventricular valves OPEN - due to lower pressure of blood within ventricles
Blood OUTSIDE the heart is under HIGHER pressure & semilunar valves are FORCED to CLOSE - this makes the "dub" sound
40
Does a person with a "fitter" heart have a higher or lower stroke volume?
Higher
41
Why does a "fitter" heart have a higher stroke volume?
To maintain the same cardiac output with FEWER beats than the heart of a LESS fit person, by working more efficiently.
42
A lower resting heart rate is a good indicator of what?
Cardiovascular fitness
43
Name some indicators of cardiovascular fitness
- Low resting heart rate
- How QUICKLY a individual returns to their resting heart rate after exercising (recovery time gets shorter as cardiovascular fitness increases/improves)
44
What happens to a persons MAXIMUM heart rate (the highest heart rate attained during all-out physical exercise) as they age?
It diminishes (decreases) - no relation to cardiovascular fitness
45
What effect(s) does regular cardiovascular exercise have on the heart?
Regular cardiovascular exercise -
- Enlarges the ventricular chambers
- Increases the distensibilty (stretchiness) of the ventricles
- Strengthens the venticle walls
This provides the heart with more POWER to push blood with each contraction
46
Name the 3 major types of vessels that carry blood within your body
- Arteries
- Veins
- Capillaries
47
What is the role of arteries?
Arteries -
- Carry blood AWAY from the heart
48
What is the role of veins?
Veins -
- Carry blood TOWARDS the heart
49
What is the role of capillaries?
Capillaries -
- JOIN with arteries and veins to allow for exchange of gases, nutrients & other materials
50
Are arterioles & venules - smaller or larger?
They are smaller
51
What is the role of arterioles & venules?
Arterioles & venules - are SMALLER arteries & veins, that carry lood into and out of - capillaries (where gax exchange occurs)
52
What is a thick-walled blood vessel carrying blood AWAY from the heart called?
Artery
53
What is a thin-walled blood vessel carrying blood TOWARD the heart called?
Vein
54
A tiny blood vessel connecting the smallest branch of an artery to the smallest branch of a vein?
Capillary
55
Largest veins in the body that carry DEOXYGENATED blood to the heart?
Vena Cavae - superior and inferior
56
A large blood vessel that carries DEOXYGENATED blood from the right ventricle to the lungs?
Pulmonary artery
57
A large blood vessel carrying OXYGENATED blood from the lungs to the left atrium?
Pulmonary vein
58
It is the largest artery in the body and carries OXYGENATED blood from the left ventricle?
Aorta
59
Define arteries
Arteries -
- Very strong
- Highly elastic with muscular walls
- Muscular walls allow the artery to EXPAND as blood flows through them - keeping blood flowing in the right direction & provides further "pumping" action
- Deal with HIGH pressure blood flow
60
Define veins
Veins -
- Thinner walls
- Larger inner circumference
- NOT as elastic
- Contain one-way valves to stop blood from flowing backwards & keep lower pressure
- Muscular contractions needed to help blood flow AGAINST gravity
61
Stretched and/or distended veins are referred to as what?
Varicose veins
62
Who is at risk for varicose veins?
- People who spend a lot of time on their feet
- Pregnant people
63
When the calf muscle is RELAXED, what occurs in the veins?
Valves in veins are - CLOSED
Blood is not moving
64
What happens when calf muscle CONTACTS?
Vein is squeezed & this pressure OPENS the TOP valve & blood moves
65
Define Capillaries
Capillaries -
- Smallest blood vessels
- 10 capillaries bundled together have same diameter as a human hair
- Walls are ONE cell thick (SUPER THIN) - allows for diffusion and facilitated diffusion across the cell membrane
- Sites of gas & nutrient exchange
- Present in networks or beds throughout body (most cells in body are located next to a capillary)
66
What is the function of an arteriovenous shunt?
Arteriovenous shunts - THRU the ACTION of sphincters, allow a capillary bed /network, to be bypassed, if the cells near the bed do not need "service" or blood is needed urgently elsewhere
67
Is capillary blood flow, fast or slow?
It is the slowest in the body
68
Why is capillary blood flow the slowest in the body?
To allow time for diffusion thru interstitial fluid & into and out of cells
69
Describe blood pressure in capillaries?
Capillary blood pressure -
LOWER than arteries
HIGHER than veins - to keep blood flowing in the proper direction
70
Name the 3 pathways blood travels thru when it LEAVES the heart?
- Pulmonary pathway
- Systemic pathway
- Coronary pathway
71
Function of the - Pulmonary pathway?
Transports DEOXYGENATED blood to the lungs for gas exchange & returns OXYGENATED blood to the heart
72
Function of the - Systemic pathway?
Carries OXYGEN RICH blood as it leaves the left ventricle & supplies it to body tissues - where gases, nutrients and wastes are exchanged
73
Function of - Coronary pathway?
- Provides blood to the heart ITSELF
- Consists of 2 coronary arteries
- The 2 coronary arteries SPLIT OFF FROM the aorta JUST as it is exiting from the left ventricle (IMMEDIATELY after the semilunar valve)
- The 2 coronary arteries SPLIT INTO smaller & smaller vessels & end in capillaries - which exchange gases with the heart muscle tissue
- The 2 coronary arteries eventually JOIN into coronary veins - entering the right ventricle
74
Define blood pressure
The pressure of blood pushing on the walls of the vessels as it flows thru the body
75
Where is blood pressure ususally measured?
In an artery in the arm.
Changes correspond to the phases of the heartbeat.
76
The maximum pressure in the blood vessels is known as what?
Systolic pressure
77
When does systolic pressure occur?
During ventricular contraction
78
The lowers pressure in blood vessels is known as what?
Disastolic pressure
79
When does diastolic pressure occur?
Between ventricular contractions
80
What is blood pressure measured in?
Millimetres of mercury (mmHg)
81
How is blood pressure measured?
Using a device called a - sphygmomanometer (blood pressure cuff)
82
What is considered a healthy blood pressure for a young healthy person?
Below 120mmHg and above 80mmHg
Represented as 120/80
83
What is "hypertension"?
High blood pressure
84
What is "hypotension"?
Low blood pressure
85
Define Hypertension
- Chonic, abnormally HIGH blood pressure
- Consistently HIGHER than 140/90
- Dangerous for the delicate blood vessels in the body (especially those of the brain, heart, kidneys and eyes)
86
What can cause a "higher blood pressure" reading?
Higher blood pressure readings can be due to -
- Individual traits
- Anxiety level
- Exercise
- Obesity
- Greater than normal amount of blood in the vessels
- Viscosity (thickness) of the blood
- Kidney disease
- Presence of chemicals in the blood - such as caffeine
- Narrowing of blood vessels due plaque buildup on artery walls
87
What are some effects of hypotension (low blood pressure)?
Dizziness, fainting
88
Functions of blood?
1. Transportation - of material & energy
- distributes signals (hormones) which coordinate & regulate the body
- removes waste - waste products & excess ions to the kidneys for excretion, CO2 to the lungs for release
2. Temperature Regulation
89
How does blood regulate the body's temperature?
1. Internal environment TOO WARM - blood vessels flowing to the skin DILATE (widen - vasodilation) - allowing more blood to flow to the skins surface to release heat.
2. Internal environment TOO COLD - blood vessels CONSTICT (narrow - vasoconstriction) - this keeps blood away from the skins surface, preventing heat loss.
- Shivering is initiated to product heat by - cellular metabolism
90
Blood is considered a what?
Tissue - it is a liquid connective tissue that links all of the cells & organs of the body
91
What is blood composed of?
Plasma & Formed portions (or formed elements)
92
What is plasma?
Fluid portion of blood
Consists (made up of) - water, dissolved gases, proteins, sugars, vitamins, minerals, hormones & waste products
93
What percentage of blood volume consists of plasma?
Plasma makes up roughly - 55% of blood volume
94
What is/are the formed portions (formed elements) of blood?
Red blood cells (RBCs)
White blood cells (WBCs)
Platelets
95
Where is the formed portion (formed elements) of blood produced?
ALL are produced in the - bone marrow
96
What percentage of blood volume consists of the formed portions (formed elements)?
Formed portion (formed elements) make up roughly - 45% of blood volume.
97
What is the blood volume breakdown by percentage?
Plasma - 55%
White blood cells & Platelets - 1%
Red blood cells - 44%
98
Another name for Red Blood Cells?
Erythrocytes
99
Describe/Define Red Blood Cells?
- Transportation for oxygen
- Bioconcave shape - allows for ease of flow through vessels
- NO nucleus
- Contain hemoglobin
- Made in red bone marrow
- Life span of 120 days
- Old RBCs are absorbed by the liver & broken down continually
100
Define hemoglobin?
- Iron containing molecule
- Has special properties allowing it to chemically BIND with (pick up) oxygen
- Can also bind with some CO2 waste
- Is a pigment giving the RBCs and whole blood it's "red" color
- Iron within hemoglobin interacts with oxygen present in the lungs
101
What is the name of the hemoglobin molecule that binds with oxygen and has a bright red color?
Oxyhemoglobin
102
Another name for White Blood Cells?
Leukocytes
103
Define/Describe White Blood Cells?
- Part of body's response to infection - protect body from pathogens & disease
- Make up roughly 1% of total blood volume
- Can double when body is fighting an infection
- Have nuclei
- Appear colorless
- Lifespan typically 13-20 days
104
How many types of white blood cells are there?
5
105
What are the names of the different types of white blood cells?
Neutrophils - (Never)
Lymphocytes - (Let)
Monocytes - (Monkeys)
Eosinophils - (Eat)
Basophils - (Bananas)
106
Define/describe Platelets?
- Fragments of cells - form when larger cells in the bone marrow break apart
- No nucleus
- Break down quickly in blood
- Key role in blood clotting
107
What is the function of blood clotting?
To prevent excessive blood loss after injury
108
Stages/Phases of blood clotting
Blood vessel injury triggers a cascade of events:
1.) Platelets - rupture when they come in contact with a rough surface. This triggers a complex series of chemical reactions.
2.) These chemical reactions cause the - dissolved fibrinogen protein - to CONVERT to its ACTIVE form - fibrin (thread-like protein).
3.) Fibrin threads - weave with each other, producing a mesh.
Mesh traps red blood cells.
More and more red blood cells get caught in the net of fibrin.
Combo of the fibrin fibres and blood cells, produces a thick, jellylike substance called a - clot.
4.) When the mesh of threads & red blood cells hardens and dries, it is called a - scab.
Skin under the scab heals and scab eventually falls off.
109
A diet high in fat does what to the walls of arteries?
Makes them rough, causing platelets to adhere to the walls, producing blood clots inside the vessel
110
What is the danger of a blood clot in an artery?
It can lead to cardiovascular issues such as heart attacks or strokes.
111
A condition where an individual lacks the ability to produce the necessary blood proteins that allow platelets to form a clot?
Hemophilia
112
Effects of hemophilia?
- Genetic disease
- Causes excessive bleeding
- Inability to clot properly
- Minor cuts & bruises take longer to heal
- Individuals often require transfusions of protein clotting factors & platelets
113
Define/Describe Plasma?
- Fluid portion of blood
- Consists of - water (92%)
blood proteins (7%)
organic substances (0.1%
inorganic ions (0.9%)
114
Functions of plasma?
Holds & transports substances such as:
- cells of blood (rbcs, wbcs, platelets)
- transports dissolved waste (carbon dioxide) from capillaries to lungs
- transports urea - waste product from the liver, filtered by the kidneys to become urine
- transports hormones from glands
- transports digested nutrients like - glucose, amino acids, vitamins, minerals
- holds & transports proteins like - fibrinogen - to aid in blood clotting
- contains antibodies (proteins) involved in immune response
115
What is a granulocyte?
A type of white blood cells that contains granules (small particles).
The granules (small particles) - are enzymes that are released during infections, allergic reactions and asthma.
116
What are the white blood cells that are considered granulocytes?
Neutrophils
Eosinophils
Basophils
117
What is the function of granulocytes and monocytes?
To engulf foreign particles.
118
What is the function of lymphocytes?
To play a role in the formation of antibodies (body's defense).
119
What is the function of platelets?
To play a role in the clotting of blood (defense function).
120
Where do granulocytes and monocytes form/originate?
Red bone marrow
121
Where do lymphocytes form/originate?
Red bone marrow & thymus
122
Where do platelets form?
Red bone marrow & lungs
123
Amount of cells present per mm(cubed) of blood?
Red Blood Cells - 5.5 million (males), 4.5 million (females)
Platelets - 250,000
Granulocytes & Monocytes - 6000
Lymphocytes - 2000
124
Size of cells (smallest to largest)?
- Platelets - 2 um (micrometres) - smallest
- RBCs - 8 um (micrometres) - small
- Lymphocytes - 10 um (micrometres) - large
- Granulocytes & Monocytes - up to 25 um (micrometres) - largest
125
Lifespan of cells, shortest to longest?
- Granulocytes & Monocytes - few hours to a few days
- Platelets - 2 to 8 days
- Red Blood Cells - 120 days
- Lymphocytes - unknown
126
What is the leading cause of death for Canadians?
Cardiovascular disease
127
Risk factors for cardiovascular disease?
- Lifestyle
- Smoking
- Obesity
- Lack of exercise
- Diabetes
- High cholesterol
- High blood pressure
- Poor diet
- Family history
128
Cardio refers to?
The heart
129
Vascular refers to?
Blood vessels
130
Cardiovascular disease affects what?
Heart & blood vessels
131
What does cardiovascular diease consist of?
Development of - plaque buildup in the arteries
Causing - reduced blood flow & higher blood pressure
132
What are the 2 types of dietary cholesterol?
High-density lipoprotein (HDL)
Low-density lipoprotein (LDL)
133
What is High-density lipoprotein (HDL)?
- Good cholesterol
- A blood protein that carries cholesterol in the bloodstream FROM body cells TO the liver
- High levesl of HDL in the blood mean it is less likely to form deposits on walls of arteries
134
What is Low-density lipoprotein (LDL)?
- Bad cholesterol
- A blood protein that carries cholesterol in the bloodstream FROM the liver to the REST of the body
- Too much LDL in blood, leads to deposits on walls of arteries.
135
How do arterial plaques form?
When there is:
NOT enough HDL (high-density lipoprotein)
OR
TOO MUCH LDL (low-density lipoprotein)
LDL builds up as plaque deposits in your arteries.
136
What are ways to REDUCE your risk of cardiovascular diesase in relation to your diet?
INCREASE intake of HDL (good cholesterol)
LIMIT intake of LDL (bad cholesterol)
137
How much of your cholesterol is made in your liver?
About 75%
138
Arteriosclerosis is?
Hardening of the arteries.
Walls of arteries become "thicker" & loose some of their elasticity.
This causes REDUCED blood flow & higher blood pressure.
139
What is the most common type of arteriosclerosis?
Atherosclerosis
140
Define atherosclerosis
Buildup of plaque on the inside walls of arteries, which narrows the arteries, restricts blood flow, and raises blood pressure.
141
What does plaque consist of?
Fatty deposits
Calcium
Fibrous tissue
142
What conditions can be caused in the body as a result of atheroscleorsis?
Angina (chest paint)
Blood clots
Shortness of breath
Heart attack
Heart failure
depending on where the plaque is located in the body
143
Treatments for atherosclerosis include?
- Medicine such as - Aspirin, which prevents platelets from forming and sticking together, reducing clot formation
- Special clot-busting medicines
- Surgical treatment such as - angioplasty, which can occur WITH or WITHOUT a stent
144
How does coronary artery disease occur?
When atherosclerosis affects the coronary arteries tha supply the heart with blood.
145
What is the effect of coronary artery diesase?
The body is not able to supply the heart with sufficient oxygen, leading to a buildup of toxic wastes.
This causes a - cramping pain, known as - angina.
146
Where is angina felt within the body?
May begin behind breastbone and radiate out toward neck and arms.
147
What is a the treatment for coronary arteries blocked by atheroscelrosis?
Coronary bypass surgery
148
Process of coronary bypass surgery?
- Segment of a healthy artery or vein is taken from elsewhere in the body & used to bypass the blocked coronary artery
- One end of new segment is attached to the aorta
- Other end is attached a point PAST the blockage
149
A blocked artery in the brain results in a what?
Stroke & cut off of blood supply to that part of the brain
150
A blocked artery occuring in the coronary arteries leads to what?
Heart attack, which cuts off blood supply and damages the heart muscle
151
Name some symptoms of a heart attack
- Chest pain - pressure, tightness, pain, squeezing or aching
- Pain or discomfort that spreads to the - shoulder, arm, back, neck, jaw, teeth
- Cold sweat
- Fatigue
- Nausea
- Lightheadedness, dizziness
- Shortness of breath
152
Name some symptoms of a stroke
- Weakness or numbness of the - Face, Arm, or Leg (usually on one side of the body)
- Trouble speaking or understanding
- Muscle weakness
- Vision problems
- Dizziness, lack of coordination or balance
- Drooping of one side of the face or body
153
Describe saturated fats
"FULL" of hydrogens
NO double bonds
Molecules are PACKED TIGHTLY together
Have a straight shape
Often solid at room temp
Raise
154
Describe unsaturated fats
Missing 2 or more hydrogens
Have double bonds between carbons
Have a bent shape
Help lower LDL (the bad cholesterol)
Raise HDL (good cholesterol)
Location of bonds determines the name.
Eg. Oleic acid - an omega 9 fatty acid - has its double bond on the 9th carbon FROM the omega at the end of the molecule
155
Why do you need a balance of healthy fats in your diet?
Healthy fats in your diet help -
- Form health cell membranes
- Help properly develop the brain and nervous system
- Produce hormone like substances that regulate body functions (eg.blood pressure)
156
What are the two important omega fatty acids in your diet?
Omega-3
Omega-6
157
Why do you need to consume omega-3 & omega-6 in your diet?
Omega-3 & omega-6 CANNOT be produced by the body.
You must obtain them from the foods you eat.
158
Sources of omega-6 fatty acids?
Sunflower, safflower, soy, sesame and corn oils
159
Sources of omega-3 fatty acids?
Fish such as - salmon, tuna, mackerel
Nuts and seeds
160
Protective effects of omega-3 fatty acids on the cardiovascular system?
- Prevents chaotic beating of the heart
- Reduces clotting of blood
- Protects against progression of atherosclerosis by reducing plaque
- Reduces inflammation
- Makes arteries more supple & elastic
- Causes slight reductions in blood pressure
161
A stretched weakness in a blood vessel is called a what?
Aneurysm
162
Where do aneurysms most often occur?
In the aorta where blood pressure is the highest.
163
Why are aneurysms dangerous?
Causes weak vessel walls that could easily burst, causing internal bleeding.
164
If an aneursym ruptures, what could occur?
Stroke or death
165
Possible causes of aneurysms?
- Hypertension
- Atherosclerosis
- Sometimes present at birth
166
How are aneurysms reparied?
Thru surgery, if the person lives long enough.
167
What is the purpose of the valves in the heart?
The valves are used to control the direction of blood
168
What can occur if the hearts valves do not function properly or they are too narrow?
Valves not closing properly causes - blood to backwash AGAINST the direction of blood flow.
Narrow valves causes - an insufficient amount of blood to be passed between the chambers, making the heart work harder to circulate the required amount of blood.
169
Replacement heart valves can be made of what types of material?
Artificial heart valves can be made from -
- plastic
- metal
- human tissue
- animal tissue
170
Which replacement heart valve material lasts longer?
Plastic or metal - but they may cause blood clots. Receipients usually take blood thinners.
171
How do most pathogens spread?
- Droplet transmission via sneeze or cough
Most colds, flus, and tuberculosis is spread this way.
172
Contaminated food, water or materials can also spread what?
- Viruses
- Bacteria
- Parasites
173
Some viral & bacterial pathogens are also spread how?
Via bodily fluids
Eg. HIV (virus that causes AIDS) is a virus that spreads thru blood and other bodily fluids
AND
Hepatitis C
174
Name 4 types of pathogens
- Viruses
- Bacteria
- Fungi
- Parasites
175
Describe/Define Viruses
- Consist of a protein "coat"
- Contain their OWN genetic material
- NOT usually considered to be alive
- Invade/Infect & use the reproductive machinery insides the "host" (living) cell, in order to reproduce
- Do not grow themselves
- Do not feed or respire (breath) - not considered cells (maybe not even considered living)
176
Describe/Define Bacteria
- Small, single-celled organism
- Contain cell wall & cytoplasm
- Genetic material "floats" in the cytoplam (is not contained in a nucleus)
- Can by sprial shape, rod shaped, or round
- Can have a whip-like tail (flagellum)
- Reproduce by SPLITTING in two (cell division)
- Able to grow exponentially
- Many, many types of bacteria
- Can be beneficial
- Can also cause illness
177
Describe/Define Fungi
- Many live on human skin, in our reproductive tracts & in our digestive tracts
- Overgrowth or invasion - of pathogenic fungi can cause illness or infection
- Organism that absorbs food in solution, directly thru their cell walls
- DO NOT conduct photosynthesis
- Reproduce thru spores
Eg. Mold, mushrooms, yeast
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Describe/Define Parasites
- Small living organisms
- Can be microscopic protozoans like - Malaria pathogen or Plasmodium vivax
- Others are large - like a tapeworm
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Name the 3 ways the body defends itself against pathogens
- Prevents pathogens from entering the body
- Macrophages & other immune cells kill "non-self" invaders (general - non specific)
- B-Cells, T-Cells & antibodies work against recognized pathogens (specific defense)
180
Name some of the physical & chemical barriers of the body that protect against pathogens
- Eyelashes
- Cilia in the respiratory tract
- Tears
- Stomach acid
- Skin
181
What is the largest barrier that protects the human body?
The skin
182
Why is the skin considered a "hostile environment" for pathogens, fungi or bacteria?
- It's dry outer layer is tough, fairly indigestible
- Keratin on the outer layer INHIBITS bacterial growth
- Oil on the skin contain bactericides
- Perspiration (sweating) - forms an acidic layer, INHIBITING microbial growth
- Clotting occurs quickly, limiting the ability of pathogens able to gain entry
183
Name 2 ways you can obtain an infectious illness
Thru -
- Food poisoning
- Contaminated water
184
How does food poisoning occur?
- Thru contaminated food or water via bacteria.
- Improperly stored food
- Improperly cooked food.
185
How long does it take for food poisoning symptoms to appear?
Anywhere from several hours, up to a day.
186
This is a disease caused by a type of bacteria often found in dirty and untreated water?
Cholera
187
What can happen if cholera bacteria are not killed?
If stomachs low pH does not kill the bacteria, they can multiply in the intestine and infect the blood supply OR they can release toxins that harm the body.
188
What is a way to prevent cholera in areas that are at high risk?
Oral cholera vaccines
189
This illness is known as "beaver fever", occuring from drinking untreated water.
Giardia
190
Name viruses which mosquitoes can spread
- Dengue
- Zika
191
What can occur to the baby if a pregnant woman contracts Zika?
It can cause - microcephaly (small head)
192
Define the term "vector"
Vector -
- organism that carries pathogens from one person to another
Eg. mosquitoes, fleas
193
What type of bacterium was spread by fleas carried on rodents?
Bubonic Plague
194
What is a protozoan?
- Microscopic Single-celled organism
- Can live as a parasite
- Requires a "host" in order to reproducew
195
What is an antibiotic?
Drug that fights bacterial infections
196
What is virome?
The viruses that live on and in us.
197
What is microbiome?
Our helpful bacteria within/on us.
198
What are antivirals?
Drugs that attempt to stop the infection of cells by viruses.
199
Process of how a "virus" inects a cell
1.) Virus attaches to host cell
2.) Genetic material (from virus) - is injected into host cell & attacks hosts nucleus
3.) The host cell is used to make new virus parts
4.) New viruses are assembled
5.) Host cell BURSTS OPEN - new viruses free to infect other cells.
200
A complex molecule located on the surface of an invading pathogen, it triggers an immune response. Short for antibody generator.
Antigen
201
Describe macrophage
- Type of white blood cell
- Engulf dead cells, cell debris & foreign cells
- Presents pathogenic antigens to T-cells in immune response
202
A type of WBC that matures in the thymus gland, can recognize & destroy invaders, ability to release chemical messengers to coordinate the immune response?
Helper T-Cell
203
What is a B-Cell?
- Type of white blood cell
- Produces antibody molecules when stimulated by Helper T-Cells
204
This is a protein molecule, produced by a B-Cell, designed to bind to a specific antigen to facilitate its destruction?
Antibody
205
What do Killer T-Cells do?
- Type of T-Cell
- Recognizes & destroys body cells by releasing proteins that create LARGE holes in target cells membrane
206
What is the role of Memory-B Cells & Memory T-Cells?
"Specialized" white blood cells
They persist in the bloodstream, providing further immunity to invaders that bear a specific antigen.
207
This is a type of T-cell that sends chemical messengers to STOP the immune response to an antigen?
Suppressor T-Cell
208
Describe the Immune Response Pathway -Step 1 thru 6
1.) Pathogens breaks the skin barrier
2.) Macrophaages (large WBCs) engulf pathogen, killing it
3.) Macrophages display - antigen markers (proteins) on their surface, which notifies the rest of the immune system that there is an invader
4.) Helper T-cells BIND to foreign antigen on surface of macrophage
5.) Helper T-Cells release - chemical signals, activating other immune cells
6.) B-cells receive message & multiply. B-cells BIND with Helper T-cell & antigen, begin making antibodies to fight against the antigen the macrophage is displaying.
209
Describe the Immune Response Pathway - Step 7 thru 12
7.) Antibodies circulate in blood & bind with any other antigens they find
8.) Antibodies INHIBIT pathogen, stopping it from invading cells, sometimes causing clumping, which makes it easier for other immune cells to find them and neutralize them.
9.) Antibody neutralized pathogens are destroyed by macrophages.
10.) Helper T-cells stimulate Killer T-Cells, to search for & kill any infected body cells.
11.) Memory B & T cells are created, to help react quickly and neutralize the pathogen for the next time.
12.) Suppressor T-Cells calm the immune response once threat is passed, to stop unnecessary damage from being done.
210
What is a vaccine/vaccination?
An injection the exposes the body to the antigens from a disease-causing pathogen.
Allows the body to make antibodies and memory b & T cells AGAINST that pathogen, without actually getting sick.
211
What may be contained in a vaccine?
- Killed/dead versions of the original pathogen
- Weakened versions of the pathogen
- A viral vector - that delivers the instruction code for making a particular protein in the pathogen, prompts cells to make the protein
- An mRNA vaccine - delivers instructions for making a certain protein from the pathogen, prompts cells to make that protein
212
What is the goal of a vaccine?
To provide your body with the innate immunity against pathogens & aid the body in eliminating a pathogen without making you sick.
213
Steps of how a vaccination works
1.) Dead or harmless forms of pathgen are injected
2.) The immune system responds by producing antibodies
3.) Memory cells ensure the antigen is "remembered"
4.) Future infections are stopped with a rapid immune response
214
What does a second exposure to an antigen that you have been vaccinated against do to the body?
Causes body to produce enormous amounts of antibodies, which neutralizes the pathogen before it can make you sick.
215
A highly contagious disease caused by the variola virus?
Smallpox
216
How was smallpox spread?
Thru coughing & sneezing, killing approx.30% of the people it infected.
217
What is the name of the person who created the smallpox vaccine?
Edward Jenner
218
What is the difference between vaccinations and inoculations?
- Vaccination - performed thru injections of antigens UNDER the skin
- Inoculation - introduce the antigen thru a cut in the skin
219
Define autoimmune disease
When the body's immune system mistakenly attacks healthy cells and tissues, thinking they are foreign invaders.
Can cause inflammatoin and affect many parts of the body.
220
Name 3 types of autoimmune diseases
- Rheumatoid arthritis
- Diabetes mellitus (Type 1 diabetes)
- Multiple Sclerosis
221
Autoimmune disease that attacks the body's joints?
Rheumatoid arthritis
222
This autoimmune disease attacks the cells in the pancreas that produce insulin?
Diabetes Mellitus
223
An autoimmune disease that attacks nerve cells?
Multiple Sclerosis
224
Ways in which autoimmune disorders can be treated?
- Immune suppressing drugs
- Treating the symptoms (such as with Diabetes Mellitus)
