Transcript lect11-6cut

Respiratory System
Respiratory System
• Sucking chest wound
– Pleural cavity __________________
– Lung collapses as air pressure difference between
pleural cavity and outside kept constant by wound
(air flows in and out of wound)
Respiratory System
• Boa constrictors
Respiratory System
• Gas transport: overall plan
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1) Heart pumps low oxygen blood to lungs
2) Oxygen in, carbon dioxide out (external respiration)
3) Blood returns to heart and is pumped to body
4) Oxygen out of blood, carbon dioxide in (internal
respiration)
Respiratory System
• Gas transport
– Oxygen non-polar: not very soluble in __________
– Hemoglobin: protein that binds with oxygen.
Contains Fe in each chain, which binds oxygen.
Respiratory System
• Red blood cell or rbc (ethrythrocyte) contains
300 million hemoglobin molecules. Each
molecule binds to 4 oxygen molecules. 1200
million oxygen molecules on 1 rbc!
Respiratory System
• Carbon dioxide transported in 3 ways:
– 1) Dissolved in plasma (67% of CO2) as bicarbonate
(HCO3-).
– CO2 + H2O forms H2CO3 which forms H+ and HCO3– This also affects pH of blood. More CO2 means lower
blood pH.
Respiratory System
• Carbon dioxide transported in 3 ways:
– 2) Bound to hemoglobin (25%). Binds to amino acids,
not to _______.
– 3) Dissolved in plasma as CO2 (8%).
Respiratory System
• Control of breathing:
– Brain stem center monitors blood pH
– If pH drops, then too ___________ CO2 in blood
– Breathing rate increased in response.
Circulatory System
Circulatory System
• Functions:
– 1. Transport of materials
(gases, nutrients, wastes)
– 2. Temperature regulation
– 3. Carries ______________
hormones
– 4. Protection (immune
defense, blood clotting)
Circulatory System
• Types in animals:
– None! Phylum Platyhelminthes, Nematoda,
Echinodermata, etc. Circulation can occur (ex,
nematodes) due to body movements.
Circulatory System
• Types in animals:
– Open. Phylum Arthropoda, Mollusca. No
capillaries: have sinuses into which blood flows
from vessels.
Circulatory System
• Types in animals:
– Closed. Phylum Annelida, Chordata. Blood
always stays in vessels as it circulates.
• Vessels:
Circulatory System
– Arteries (carry blood away from heart): large
diameter
– Thick elastic muscular walls. Can handle high
blood pressure
– Connective tissue sheath outside, _____________
inside.
Circulatory System
• Vessels:
– Arterioles (carry blood away from heart): small
diameter (microscopic)
– Smooth muscle controls blood flow.
Vasoconstriction is contraction to cut flow down
– Vasodilation is relaxation to increase flow.
Circulatory System
• Vessels:
– Precapillary sphincters: __________ muscle valves on
some arterioles near capillaries. Can cut off blood flow
– Important: most capillaries not open simultaneously
(blood pressure would drop critically). Parts take
turns.
Circulatory System
• Vessels:
– Capillaries: very small diameter (8 micrometers:
rbc only 5-7 micrometers wide). Where most
exchange of materials takes place
– Every cell in body within _______ micrometers
of a capillary!
– 250,000 capillaries in area size of little fingernail.
Circulatory System
• Vessels:
– Capillaries connect arteriole to _______________
– No smooth muscle, just endothelium (note
diagram in error: capillary on upper right).
• Vessels:
Circulatory System
– Venules (carry blood toward heart): small diameter
(microscopic)
– Smooth muscle thin. Pressure low (________% of
arteries). Connective tissue sheath outside,
endothelium inside
– Veins (carry blood toward heart): large diameter
Note: labels for vein and
capillary are reversed in
diagram
Circulatory System
• Vessels:
– Veins often have one-way valves. Muscle
contractions can help move blood through valves.
Circulatory System
• Vessels:
– Varicose veins: weakened valves in legs allow
backflow. Small veins bulge with venous blood.
Circulatory System
• Lymphatic system: open
circulatory system
Circulatory System
• Blood plasma in tissues (_________________ fluid)
bathes tissues. Not all returns to capillaries
• Lymphatic capillaries, vessels, nodes, organs (nodes)
• Capillaries collect fluid (lymph) and pass to larger
lymph vessels
Circulatory System
• Lymphatic system vessels: little smooth muscle in
walls
• Have series of one-way valves. Fluid moves mainly
due to contraction of nearby __________________.
Fluid moves
left to right
here
Circulatory System
• Lymph system functions
• 1) Drain excess fluid
from tissues (recall
elephantiasis, where
nematodes clog system)
Circulatory System
• Lymph system functions
• 2) Involved in fat absorption from intestine
(covered).
Circulatory System
• Lymph system functions
• 3) Fights infection at lymph
nodes (about 100 in human
body)
– Bean shaped, various places.
Circulatory System
• Lymph system functions
• 3) Nodes produce B- and T-lymphocytes. These produce
antibodies that detect foreign materials (ex, bacteria)
– Nodes become swollen in areas downstream of infection as
lymphocytes attack invaders
Heart
• Major organ of circulatory system
• Enclosed in membrane called
____________________
• Pumps blood into arteries.
Heart
• Humans have 4 chambered heart
that functions in 2 sets of 2
chambers (form 2 myocardia)
• Chambers called atria receive
blood, pump it into more muscular
chambers called ventricles, which
send blood away from heart.
Heart
• One set receives deoxygenated blood and sends it to lungs
(pulmonary circulation)
– Right atrium (receives deoxygenated blood) from superior (from
head) and inferior (from lower body) vena cava
– Right ventricle (pumps it to lungs) via pulmonary artery.
Heart
• Second set receives oxygenated blood from lungs and
sends it to body (systemic circulation)
– Pulmonary vein brings oxygenated blood to left atrium
– Left ventricle pumps oxygenated blood to body via _______.
Heart
• Note valves: prevent backflow of blood when
chamber contracts
• Tricuspid valve: between right atrium and ventricle
• Bicuspid valve: between left atrium and ventricle.
Heart
• Note valves: prevent backflow of blood when
chamber contracts
• Semilunar valves (aortic and pulmonary): between
ventricles and arteries that receive blood from them.
Heart
• Chordae tendinae and papillary muscles keep
bicuspid and tricuspid valves taught.
Heart
• Beating controlled by special groups of cardiac muscle
cells (called nodes) that generate impulse
• Other cells then transmit impulse to one another via
intercalated discs.
Heart
• SA node (right atrium) originates __________
• Causes atria to contract (ventricle relaxed at this time).
Heart
• AV node receives stimulus
• Sends to ventricle cells through specialized cardiac
muscle cells called Purkinje fibers
• Ventricle cells then contract (after atria relax).
Heart
• Heart sound: Lub-dub
• Lub: biscuspid and tricuspid valves closing as
ventricles contract
• Dub: aortic and pulmonary semilunar valves closing
as _________________ re-fill.
Heart
• Autonomic nervous system influences
heartbeat rate
– Sympathetic nerves: accelerate rate
– Parasympathetic nerves: slow rate
– Some hormones (ephinephrine = adrenalin):
accelerate rate.
Blood
• Connective tissue: cells in matrix
• Matrix: plasma.
Blood
• Plasma components:
– 1. Water (92%)
– 2. Salts (Ca, K, Na)
– 3. Proteins
• globulins: large immunoglobins (antibodies)
• albumins: osmoregulation (most abundant blood protein)
• fibrinogen: helps clotting. Serum is plasma minus fibrinogen
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4. Glucose (regulated by glucagon and insulin)
5. Glycerol and fatty acids
6. Hormones
7. ____________ (nitrogenous waste)
8. Carbon dioxide and bicarbonate
Blood
• Cells (called formed elements)
– Erythrocytes (red blood cells: rbcs): no nucleus,
biconcave disc shape, flexible. Origin: ___________ bone
marrow.
Blood
• Cells (called formed elements)
– Leukocytes (white blood cells: wbcs): have nucleus. <1%
of blood cells.
Blood
• Cells (called formed elements)
– Granular leukocytes (granulocytes)
• Lobed nucleus and look grainy
• Phagocytic cells. Fight infection, produced by ___________
marrow
• Types: neutrophils (stain well with neutral pH dye), basophils
or mast cells (stain well with basic pH dye), eosinophils (stain
well with eosin).
Blood
• Cells (called formed elements)
– Agranular leukocytes
• Large nucleus, no granules present
• Formed in lymph nodes
• Types: Monocytes (become macrophages in tissues, largest
phagocytic cells, nucleus kidney bean shaped), Tlymphocytes (phagocytes), B-lymphocytes (make
___________________)
Blood
• Cells (called formed elements)
– Thrombocytes (platelets)
• No _____________. Fragments of red bone marrow cells
• Function in clotting of blood.
Blood Summary
• Cells (called formed elements)
– Thrombocytes (platelets)
• No nucleus. Fragments of red bone marrow cells
• Function in clotting of blood
Blood Clotting
• Blood vessel wall
broken
• Platelets stick to each
other and to break.
Release clotting
factors.
Blood Clotting
• Protein called
prothrombin
converted to
thrombin, which
causes fibrinogen in
plasma to become
fibrin (protein
threads)
• These threads bind
together platelets and
blood cells to make
____________.
How Phagocytic WBCs work
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Damage to tissues
Mast cells release histamine
Causes blood vessels to dilate
Increases permeability of capillaries.
How Phagocytic WBCs work
• Neutrophils and _____________ stick to lining of
capillary
• Squeeze through wall into tissue
• Locate and digest invading cells.