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Respiration: involves
1. Breathing
2. transport of gases
3. exchange of gases: O2 for cellular respiration and removal of waste CO2
RESPIRATORY SYSTEM
1. Breathing: active pumping of air in and out– Inhalation- muscular contraction causes chest cavity to expand– Exhalation- ribs and diaphragm return to their original position
• human breath: moves 0.5 L of air-tidal volume• extra amount forced into and out of the lung, 4.5 L in men and
3.1 L in women- vital capacity• air remaining in the lung, 1.2 L-residual volume or dead
volume
2. Transport of gases
- air inhaled through the nostrils
- Passes through the pharynx and larynx
- into the trachea, bronchi, and bronchioles
• Lungs: air inhaled mixes with old air already in the lung
• inner surface many small chambers called alveoli
-
(Heart)
Diaphragm
Bronchiole
Bronchus
Right lung
Trachea
Larynx(Esophagus)
Pharynx
Nasalcavity
Left lung
3. The bronchioles end in clusters of tiny sacs called alveoli: Where gas exchange occurs
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Blood transports respiratory gases:
• The heart pumps oxygen-poor blood to the lungs>>>> picks up O2 and drops off CO2
• Then the heart pumps the oxygen-rich blood to body cells>>> drops off O2 and picks up CO2
Exhaled air Inhaled air
Air spacesAlveolarepithelialcells
CO2 O2
CO 2 O2
CO2-rich,O2-poorblood
O2-rich,CO2-poorblood
HeartTissue
capillariesCO2
O 2
Interstitialfluid
CO2 O2
Tissue cellsthroughout body
Alveolarcapillaries of lung
• Hemoglobin, in red blood cells, carries O2 and helps transport CO2 and buffer the blood
0
Iron atom
Heme group
O2 loadedin lungs
O2 unloadedin tissues
Polypeptide chain
Smoking
342,000 Americans
die of lung disease
90% lung cancer cases due
to smoking
Other cancers: mouth, throat,
bladder, pancreas, other organs
Smoking
Lung and air sacs are very delicate!!!
Particles easily produce damage
Healthy Lung Diseased LungSmoker’s Emphysema
DeoxygenatedBlood
OxygenatedBlood
OxygenatedBlood
DeoxygenatedBlood
Circulation and Respiration
functions
1) Transports O2 and CO2
2) Distributes nutrients
3) Transports waste products/toxic substances
4) Distributes hormones
5) Regulates body temperature
6) Clots blood
7) Protects body (immune system)
CIRCULATORY SYSTEM
circulatory system (cardiovascular system) parts:– heart—a muscular
pump that pushes blood through the body
– blood—fluid that circulates through the vessels
– blood vessels—a network of tubes through which the blood moves
heart• contraction of the
muscle • Parts: 2 top
atria, 2 bottom ventricles
• Valves: heart flaps that maintain direction of blood flow
Right Atrium
Right Ventricle
Left Atrium
LeftVentricle
RIGHT
ATRIUMLEFT
ATRIUM
RIGHT
VENTRICLE
LEFT
VENTRICLE
Blood Vessels
Artery Artery
Vein Vein
Blood
• Blood plasma • metabolites and wastes:
glucose, vitamins, hormones• salts and ions: sodium, chloride,
and bicarbonate• Proteins: help osmotic balance,
antibodies, fibrinogen for blood clotting
Blood – Red Blood Cells (RBC)
Function: carries O2 in blood
99% cells
Hemoglobin
Blood – White Blood Cells
Function: Protection from foreign invasion
Blood - Platelets
Function: Blood clotting
Blood Vessels
Network of channels where blood flows through
Arteries = carry blood away from heart
Veins = carry blood towards heart
Capillaries = thin vessels
Molecule exchange
The structure of blood vessels
- Artery- layers of the arterial wall are elastic to expand with the pressure caused by contraction of the heart- Veins- return blood to the heart, walls are thin, have unidirectional valves that prevent the flow of blood backwards- Arterioles and venules- small in diameter
-Capillaries-where oxygen and food molecules are transferred from the blood to the body’s cells-narrow and thin walls>> slow blood flow, one cell at a time
Cardiovascular Diseases
Disease of heart and blood vessels: Leading cause of death in US (871,500 in 2004)
• Hypertension – high blood pressure• heart attacks- insufficient blood reaching heart• Strokes- interference in blood to the brain• Atherosclerosis- accumulation within the
arteries that cause a reduction in blood flow
Atherosclerosis – hardening of arteriesPlaques form and clot the blood flow
IMMUNOLOGY
• Innate defenses against infections>> include the skin and mucous membranes, phagocytic cells, and antimicrobial proteins
>> present and effective long before exposure to pathogens
• world’s 7 deadliest diseases
Viral Diseases
• Infect-kill many more people
• Ex: – Influenza: biggest killer virus worldwide– West Nile– SARS – hepatitis – HIV
DEFENSES
• Physical defense:– Skin
• chemical defense: – oil glands make the skin surface very acidic– sweat contains enzyme lysozyme, which attacks and digests the
cell walls of many bacteria– Eyes: tears contain lysozyme to fight bacteria– digestive tract: stomach acid and digestive enzymes provide
protection in the digestive tract– respiratory tracts: sticky mucus traps most microrganisms in the
respiratory tract
• Lymphatic system
SKIN:– epidermis:
• 10 to 30 cells thick• cells are shed
continuously
– dermis:• 20 times thicker• structural support • fat-rich cells for shock
absorbers and insulation
LYMPAHTIC SYSTEM
- crucial battleground during infection
- is a network of:- lymphatic vessels - organs
- Major functions:1. central storage and distribution
of white cells2. returns proteins to circulation,
if remain in the tissues causes swelling or edema
3. transports fats absorbed from the intestine
Adenoid
Tonsil
Lymph nodes
Right lymphatic duct, entering vein
Thymus
Appendix
Thoracic duct
Bone marrow
Lymphatic vessels
Spleen
Thoracic duct, entering vein
Lymph node
Masses of lymphocytes and macrophages
Valve
Lymphatic vessel
Blood capillary
Tissue cells
Interstitial fluid
Lymphatic capillary
- vessels collect fluid from body tissues>>> return it as lymph to the blood- Lymph organs, spleen and lymph nodes, are packed with white blood cells that fight infections
•The immune response – The immune system encounters foreign
molecules called antigens
– The immune system reacts to antigens and “remembers” an invader
• The temperature response: fever:– body’s thermostat rises above the normal
37°C – human pathogenic bacteria do not grow
well at high temperatures– fever curbs microbial growth but it can be
dangerous because it might inactivate critical cellular enzymes
• The inflammatory response mobilizes nonspecific defense forces– Tissue damage releases signals, such as prostaglandins and
histamine– causes the blood flow to increase and capillaries stretch– phagocyte cells migrate to the site of infection and attack the invaders– many of these cells die and form the pus of the curing infection or
wound
White blood cells : to kill invading microbes:– Macrophages: ingest
bacteria– natural killer cells:
attack body cells that are infected by puncturing the membranes and allows water to rush in burst the cell (CANCEL CELLS)
White blood cells: LYMPHOCYTES– T cell :
– origin bone marrow,maturation in thymus
– Attack cells infected with pathogens
– B cell: • Origin+maturation in bone marrow• produce antibodies that attack
antigens
– Memory cells: derivatives from B/T cells after an exposure to an antigen
Bone marrow Thymus
Stem cell
Immature lymphocyte
B cellHumoral immunity
Via blood
Antigenreceptors
Via blood
T cellCell-mediated
immunity
Lymph nodes, spleen, and other lymphatic
organs Final maturation of B and T cells in lymphatic organ
Other parts of the lymphatic system
Antibodies– proteins in the immunoglobulin (Ig) family: IgA, IgD,
IgE, IgG, IgM; 109 diff Ab– promote agglutination, external secretions, release of
histamine
HIV• 2nd biggest killer virus:
people infected 42 mill• Drugs help live longer
• destroys T cells, compromising the body’s defenses opening the way for opportunistic infection>> Kaposi’s sarcoma
Vaccination
1. introduction of a dead or disabled pathogen
2. triggers immune response against the pathogen
3. body response by making: Ab and memory cells so second infection is halted much earlier
flu epidemic (1918) killed 20 million people
in 18 months
The house dust mite
Allergies are overreactions to certain environmental antigens due to abnormal sensitivities to antigens (allergens) in the surroundings
An allergic reaction
Resistance to Antibiotics
• Rabidly producing infectious bacteria are becoming genetically resistant to antibiotics due to:– Genetic resistance: Spread of bacteria
around the globe by humans, overuse of pesticides which produce pesticide resistant insects that carry bacteria.
– Overuse of antibiotics
• EX: Global Threat from Tuberculosis
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