Download Circulatory System - La Salle Elementary School

Circulatory System
Chapter 4
4-1
The Body’s Transportation System
• Main job of circulatory system
– Delivers food & Oxygen to cells
– Carries Carbon Dioxide & other waste
products away from cells
• Powered by Heart
• Blood vessels are main passage
– Extremely extensive (large, complex)
• Oxygen & food = Energy
– Energy needed for cell life
– 1st to die w/o Oxygen – Brain Cells
• Important tasks of Circulatory System
– Delivery of Oxygen to body cells
– Removal of Carbon Dioxide
– Supplies body with defenses (chemicals)
against Bacteria/Viruses
– Carries chemical messengers for
communication
4-2
Circulation in the Body
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Heart → Lungs → Heart
Blood→ Body Cells→ Heart
Heart = muscle (only rest btwn beats)
Anatomy of Heart
– Left chest
– Fist or grapefruit
– Heartbeat = rhythm
– Pacemaker – area of nerve tissues that
regulate the heart’s pace (upper right side of
heart)
• Regulates muscle contractions of heart
Right Side
• 2 pumps in Heart
– right & left sides
– Septum (thick tissue wall) separates the 2 sides of heart
– 2 chambers on each side
• Right Atrium
– Collecting chamber
– Dark red, Oxygen-poor blood
– Receiving blood from body carrying waste Carbon Dioxide
• Right Ventricle
– Valve divides the 2 chambers
– Pumping chambers
– Leaves heart through large vessel
– Pumps blood to Lungs
To the Lungs and Back
• Right ventricle pumps blood to lungs
– RBC drop off carbon dioxide (exhaled)
– RBC pick up oxygen (inhaled)
– RBC carry oxygen to body cells
– Hemoglobin + Oxygen = Oxygen-rich
blood (bright red)
– Oxygen-rich blood enters back into heart
• Left Atrium
Left Side
• Left Atrium – collecting chamber
– Oxygen-rich blood flows through valve
– Enters left ventricle
• Pumps blood throughout body
• Left side works abt 6x harder than right
side
Arteries: Pipeline from the Heart
• Carry blood away from the heat
• Aorta – largest blood vessel in the body
– Arteries branch out sending oxygen-rich blood
throughout the body and some back to the heart
– 3 layers
• Smooth inner layer (easy flow)
• Elastic middle layer (smooth muscle tissue)
contract/relax to move blood
• Outer layer (flexible connective tissue) stretch
and return to normal size with heartbeat
• Blood is sent to body location according to priority
– Eating, exercising, waste removal, repair
• Blood always goes to the brain
Capillaries: The Unseen Pipelines
• Thin walled vessels (RBC in single file)
• Blood’s work occurs here
– Remove oxygen and pick up waste
– Pass in and out of capillaries thin walls
– Blood becomes dark red (no oxygen)
Veins: Pipelines to the Heart
• Blood trickles capillaries →veins → heart
• Veins thicker that capillaries but thinner that
arteries
– One-way valves to prevent blood from
back-flowing
Blood – The River of Life
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Blood – tiny particles floating in a fluid
Fluid tissue (1 of 2 in body: Lymph)
4 Components of Blood:
Floating particles:
– Red blood cells
– White blood cells
– Platelets
• Fluid portion:
– Plasma
Plasma
• 90% water
• 10% - sugars, fats, salts, gases, plasma
proteins
– 3 Groups of Plasma Proteins
• Regulate amt of water entering & leaving
blood
• Antibodies – special proteins to help fight
of diseases
• Blood clotting
• Plasma carries digested food, hormones and
waste products
Red Blood Cells
• Most numerous in body
– Look like tine berets
– Centers very thin, enabling them to bend in
order to move through capillaries
• Produced in bone marrow
• Contains a nucleus in early stages but then
shrinks as cell ages
– Very delicate & only live for abt 120 days
– Die at a rate of 2million/sec
– New rbc form at abt the same rate
– Old/dying rbc broken down in liver & spleen
• Spleen: aka “cemetery” of rbc
• Hemoglobin – iron-containing protein found
in rbc
– Build-up of hemoglobin forces out nucleus
– Oxygen binds with hemoglobin to be
carried throughout body
– Binds with carbon dioxide also
White Blood Cells
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Larger than rbc and live longer (mths or yrs)
Developed in bone marrow
Keep nucleus
Main function to protect body from disease,
bacteria, viruses, etc
– Surround and digest invaders
– Make antibodies
– Produce special chemicals to fight
diseases
Platelets
• Aid in the clotting of blood
• Platelets burst open when a cut occurs
producing the chemical Fibrin
– Act as a net, weaving a fiber across a cut
trapping plasma and cells
– Hardens and then clots (scab)
• Fragments of cells
– No nucleus, no color
– Break off from larger cells produced in
bone marrow
Blood Groups
• Transfusion – transferring of blood from 1
person to another
• Clumping chemicals – proteins on the outer
coats of rbc that react with different proteins
• A and B: proteins in red blood cells
• anti A and anti B: proteins in the plasma
– Named for their reaction to A & B
• 4 Basic Blood Groups
–A
–B
– AB
–O
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A people contain A protein
B people contain B protein
AB people contain A & B proteins
O people contain neither A or B proteins
Transfusions must be compatible
– Donor – person giving blood
– Recipient – person receiving blood
– Both tested to find out blood type
• anti A & anti B chemicals needed when wrong
blood type is not used or available in a
transfusion
• O blood type contains A& B anti chemicals
– anti A causes rbc containing protein A to
clump together
– anti B causes rbc containing protein B to
clump together
• A blood receive A or O
• B blood receive B or O
• O blood only receive O
• AB blood receive A, B, AB & O
• Rh Blood Group
– 18 other proteins found on the surface of
rbc
– Found on rhesus monkeys
– Rh+: contain any 1 of the 18 proteins
– Rh-: do not contain any of the 18 proteins