Download Chapter 1- Circulation and Immunity

SCIENCE 30
UNIT A: MAINTAINING HEALTH
Chapter 1- Circulation and Immunity
Mrs. Steinbrenner
Name:
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1.1) Circulatory System
Descending aorta
• 4 main roles of the circulatory system:
– _____________ (gases, nutrients, wastes).
chordae tendinae
– Regulation (by hormones).
(a.k.a. aortic valve)
– Protection/Defense (immunity and injury).
(a.k.a pulmonary valve)
– Distributes ________________.
(a.k.a bicuspid or mitral valve)
(a.k.a tricuspid)
• Divided into 2 parts:
– 1. ______________________ (heart, blood
septum
apex
vessels).
– 2. Lymphatic system ( lymph vessels and
nodes).
Ideas about the heart
• Historical ideas:
–
________: Greek physician (2nd century)
•
Believed that heart sucked blood from veins, blood flowed like the tides.
–
___________________: 15th century
•
Complete and realistic sketches of the heart.
–
William Harvey: 17th century
•
Discovered __________ in heart and veins, 1 way movement of blood.
•
Calculated cardiac output.
•
Aided by ___________ discovery of capillaries.
A. Cardiac Output
• The ___________________ that flows from each side of the heart per minute.
• Two factors affect this output:
1. _____________: quantity of blood pumped with each beat of the heart (~ 70mL).
2. Heart rate: # of times heart beats/minute.
Cardiac output = ______________________
Applications of Cardiac Output
Provides comparison for fitness levels:
- ______ heart rate = high stroke volume.
- High heart rate = ______ stroke volume.
B. The heart
• There are 4 chambers in the heart:
– Left and Right _________ (receive blood from lungs and body).
– Left and Right _______________ (pump blood to lungs and body).
• Double sided pump: Left and Right sides of the heart are separated by a muscular wall
called the ________________.
• The sac that encloses the heart = ______________________. Fluid inside is called the
pericardial fluid.
1) The Heart Pumps
• There are 2 pumps that work simultaneously; these are synchronized.
• Left pump = ____________ blood received.
• Right pump = _________________ blood
received.
2) Blood Flow- Low oxygen
• Blood low in oxygen (from the body)
enters the ______________ and is pumped
Descending aorta
to the right ventricle.
• The right ventricle pumps deoxygenated
chordae tendinae
blood to the ______________________
(a.k.a. aortic valve)
(a.k.a pulmonary valve)
(a.k.a tricuspid)
(a.k.a bicuspid or mitral valve)
2
septum
apex
and then to the lungs. This blood is then oxygenated.
Blood flow- high oxygen
• Blood high in oxygen (from the lungs) enters
__________________ to the left atrium.
• The ________________ pumps blood to the left ventricle,
pumped to the aorta, to the arteries and then to the body.
• Arteries divide into arterioles and then into capillaries. All
gas, nutrient and waste exchange happens using the
__________.
Blood flow
• Capillaries branch into venules,
becoming veins, then the
_______________ and blood
enters the right atrium.
• Why is the left ventricle (8-10mm) thicker than the right ( 2-3
mm)? ________________
Vena Cava
The largest vein in the body. There are 2 branches of the vena cava:
1. _____________ Vena Cava (receives blood from the diaphragm
up).
2. ___________ Vena Cava (receives blood from below the
diaphragm).
3) Heart Valves
• Valves open and close to let the blood flow through the heart.
• 2 types:
– ________________ (AV) valves: between atria and ventricles.
• Open when atria contract, close when ventricles contract.
–
__________: between ventricles and arteries.
• Open when ventricles contract, close when atria contract.
4) Heartbeat
• “lub-dub” sound caused by closing of heart valves.
• “lub”= ___valves close (ventricles contract)
• “dub”= _____________ valves close (atria contract).
• “gurgle” = heart murmur (valves do not close properly).
• _________ = ventricular relaxation (“dub”).
• ________ = Ventricular contraction (“lub”).
5) Factors affecting heart rate
• Many factors affect heart rate including:
– ______________________.
– Temperature change (↑ temp = ↑ HR).
– Cardiovascular exercise (running, swimming, cycling) can decrease heart rate.
• A stronger heart is ______ a larger heart but a more elastic/efficient one!
6) Target Heart rate
• Once your body reaches 85% of its max. HR, lactic acid is made and pain increases.
• To calculate target HR, use: _____________ = target HR
Target Heart Rates
Health goal
% of maximum HR
Maintain fitness level
50 -60%
Increase fat burning
60-70%
Increase cardio
70-80%
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1.2) Blood Vessels
• 3 types of blood vessels in the body:
1. Artery: take blood _______ from the heart.
1. Thick elastic walls that can stretch.
2. Vein: takes blood ____ the heart.
1. Thin walled with valves for 1 way flow.
3. Capillaries: connect arteries and veins.
1. 1 cell thick to allow ___________ into cells.
1)Blood pathway in vessels
• Heart --- arteries ---- arterioles ---- capillaries ---- venules ---- veins ---- vena cava --heart.
• Arterioles and venules are just smaller versions of arteries and veins.
• Arteries always carry _______________ blood (except for pulmonary artery).
• Veins always carry ________________ blood (except for pulmonary vein).
• Pressure ___________ as you get to the capillaries; builds going back to the heart.
2) Varicose veins
• Raised veins due to damaged valves and stretched walls.
• Blood _____________________ veins.
• Prolonged standing can cause this.
3) Blood Pressure (BP)
• The force of blood against the artery walls during ventricular contraction (systole) and
during atrial contraction ( diastole).
Heart rate = ______________________
_________= 120/80 (average)
• ____________ is most important because it determines the pressure on arteries when
ventricles are relaxed.
• Measured using a sphygmomanometer.
a) Factors that affect BP
1. Heart rate (HR): High HR = high BP.
2. Blood vessel size: _________ = high BP.
3. Blood volume: High volume = high BP.
4. Stroke volume: High volume = high BP.
b) Regulation of Blood Pressure (BP)
• ___________ = difficulty transporting blood to tissues (especially head).
• ____________ = weaken artery, ruptures blood vessels.
• __________________ (in aorta and carotid arteries) detect changes in BP. Brain receives
message and either speeds up (sympathetic) or slows down (parasympathetic) impulses.
c) Hypertension: The Silent Killer
 High blood pressure
 Caused by increased resistance to blood flow
 Blood vessels weaken and may rupture
 Body compensates by increasing support provided by connective tissues
 Arteries become _____________
 During systole, blood pressure increases even more; Further stress and
weakening
Causes of Hypertension
1. Hereditary
2. _________
 Excess salt
 High fat
 Silent killer: Symptoms not noticeable until a heart attack or stroke results
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d) Pressure and Blood flow
• As the area that blood flows through increases, the pressure ___________ (because
velocity does too).
• Blood travels the slowest through the capillaries; allows for all nutrients to be picked up!
• Velocity of blood _____________ from arteries --- capillaries --- veins.
•
1.3) Blood
• Average 70kg person has ____ of blood.
• 55% of blood is fluid,45% is blood cells.
• __________ = fluid; 90% water and 10% proteins, vitamins, glucose...
• There are 3 groups of proteins in plasma:
1. Albumins: draws water back into capillaries
2. Globulins: produces antibodies
3. Fibrinogens: used to clot blood.
A. Red Blood cells (_________________)
• Make up ________ of blood cells.
• Main function = transport __________ (each rbc can have 4 oxygen molecules).
• Respiratory pigment hemoglobin allows rbc’s to carry oxygen ( 70x more than without
hemoglobin)- gives red color!
• Without hemoglobin, life can be maintained for _____; with = 5 minutes.
• ______________ shape to maximize SA for gas exchange.
• Enucleated = ________________ when mature, allows for more oxygen to be carried.
Bone marrow produces rbc’s, can not reproduce without a nucleus.
Bone marrow
• Erythropoiesis = _________ production ( occurs in bone marrow).
• Rbc’s begin as stem cells, divide and shrink- losing nucleus.
•
Age of rbc’s is monitored by wbc’s; when rbc is _________ days, it releases hemoglobin
and is transported from the cell.
• Iron (globin) is recycled and used in new rbc’s; heme is converted into _______ pigments
(bilirubin).
B. White blood cells (__________)
• Around ____ of blood.
• Responsible for: housekeeping/ defence.
• Have a nucleus.
• Made in bone barrow; last _____________ days.
• Destroy invaders by:
– __________________: move towards microbe. Enzymes released digest
leukocyte and microbe; fragments = pus.
C. Platelets (thrombocytes)
• Have no nucleus.
• Produced in bone marrow; last ____ days.
• Irregularly shaped, very _________ and responsible for blood-clotting reactions.
D. Blood Clotting
• Maintains homeostasis.
• Platelets ___________ when striking a sharp object .
• Fibrinogen breaks up into fibrin threads. These seal the cut: prevent bacteria from
entering and create framework for ___________ to patch up cut.
• A _____________ is a blood clot that seals the vessel = blocks vessel and prevents gas
exchange.
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•
•
•
•
•
2 types:
Cerebral: clot in brain, causes a __________
Coronary: clot in artery, causes ___________________.
Embolus = dislodged blood clot, travels to other organs; life threatening
Hemophilia: The ability to produce fibrinogen to form a clot is hindered.
• Czar Nicholas II son had hemophilia.
1.4 Cardiovascular diseases and disorders
• There are many diseases that affect the heart and blood vessels:
– Atherosclerosis ( hardening of arteries due to plaque).
– Coronary Heart disease ( ________________ _________ to artery(s) of the
heart).
– Heart Attack ( no blood flow to coronary artery).
– Stroke (no blood flow to brain).
– _______________ ( bulging of artery or vein).
– Septal Defect ( septum is not completely closed- “___________________”).
a) Plaque and cholesterol
• Cholesterol that is deposited on the artery is called ___________.
• ________ fats are “bad” because they build up in the artery (found in saturated fats).
• _________’s are “good” because they take LDL’s away to the liver (found in fish, etc).
b) Atherosclerosis
c) Problems with the heart
• _____________= chest pains that occur when too little oxygen from the coronary arteries
reach the heart.
• Treatment:
– Drugs to reduce plaque in arteries.
– Coronary __________ surgery (used in severe cases, grafts a new vein to the
heart around the blockage). Heart must be stopped to do this!
1.5 Immune system
• Pathogens (an agent that causes disease) enter the body in many ways:
– Protozoans (______________): example – malaria.
– Fungi ( mold, etc): example – athlete’s foot.
– Bacteria (rapidly reproduce; stopped by antibodies): example – __________.
– Viruses (infect host cell and reproduce DNA): example- __________, cold virus.
1) Immune response
• 2 lines of defence:
– 1st line = primarily _________ (skin, mucous).
– 2nd line = within the body (______________ produced).
• 1st line: Non-specific Immunity
– Barriers: skin mucous, cilia.
– ____________: wbc’s engulf the foreign invader (packman)- releases pus.
– Fever: raises body temperature to 40° destroy bacteria (at _____ all cells die).
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a. 1st line : Physical
 Mainly physical
 ___________ – protective
o Acidic secretions (pH of 3 – 5)
 Respiratory tract (windpipe) – mucus and cilia sweep foreign material away from lung
 ________________ – acids and protein digesting enzymes destroy microbes
 Tears, saliva, mucous secretions – ____________ (enzyme) destroys bacterial cell walls
b) 2nd line: specific Immunity
• Lymphocytes: produced in bone marrow and seed in _________________.
• When a foreign antigen (protein) is present, immune system responds. Foreign cell has
different antigen markers than body cells; this ______________________.
• Complement proteins (in plasma) activated by foreign microbes, _________ to invader
and help phagocytes.
• 2 Types: ____________________.
1. B cells
• Formed and mature in the ____________.
• Each b cell produces a single type of antibody.
• Plasma cells can produce up to 2000 antibody molecules/second.
• Recognize the foreign antigen and start dividing into 2 groups:
1. ____________: provide life-time immunity.
2. _______________: produce antibodies that stick to antigen and disable the
invader.
2. T cells
• Formed in bone marrow, mature in ________________________.
• Recognize foreign protein on cell membrane and divides into 4 types:
1. Memory cells: Provide lifetime immunity.
2. ___________ cells: secrete cytokines that activate B cells and Killer T-cells.
3. Killer T cells: cytotoxic cells = _________ any infected body cells; destroy
mutated cells. Responsible for rejection of organs (transplantation).
4. __________________ T cells: shuts down immune response.
c. Antibodies
• ______ shaped proteins that target foreign invaders.
• Specific to the antigen on the invader.
• Each antibody has a complementary shape to it’s antigen; each antibody will only attach
to a _______________.
• Larger molecule is then engulfed by macrophage (phagocytotic wbc’s).
• Invaders can’t access the cells and can’t pass through cell membrane- await death.
• Body contains ____________ different antibodies
Immune response
• Bacteria enters----macrophage attacks ----helper T cells release lymphokine ---____________ activated--- antibodies released --- released into circulatory system.
• B cells also activate ____________ cells ---- puncture cell membrane or attack cell
membrane of infected cell (by virus)--- kill cells.
• Once foreign cells destroyed _______________ T-cell stops immune response---- body
maintains antibodies to kill antigen--- ________________ clean debris and tissues repair.
2) Vaccinations
• Memory T cells can provide immunity to viruses; you never get sick from the same 1
twice.
• Vaccinations are a __________________ ______________ of the virus injected,
antibodies are produced and immunity is created.
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3) Autoimmune Disorders
 Immune system mistakenly attacks body cells
o Renegade lymphocytes treat body’s cells as foreign and attack cells (Usually held
in check)
o Mutated _____________________.
o Theory: suppressors secrete a substance that tells macrophage to engulf renegade
cells
o Examples: Lupus,_____, Type 1 diabetes, AIDS.
Causes
 Weakening of suppressor T cells:
 Drugs or serious infections
 Decline with age
 Some people are born with defective suppressor T cells
 Treatment
 ___________________________ drugs
Reduce intensity of renegade cells.
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