Chapter 15. The Cardiorespiratory System Includes function of the heart, blood vessels, circulation,...
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The Circulatory System Chapter 15
Chapter 15. The Cardiorespiratory System Includes function of the heart, blood vessels, circulation, and gas exchange, between the blood and atmosphere
The Cardiorespiratory System Includes function of the heart,
blood vessels, circulation, and gas exchange, between the blood and
atmosphere. Heart pumps blood through the body through pathways
(arteries, veins, and capillaries) Blood is enriched with oxygen
when it passes through the lungs As oxygen enters the bloodstream,
carbon dioxide leaves it (respiration)
Slide 3
The Circulatory System Course taken by blood through the
arteries, capillaries, and veins & back to heart Uses blood to
transport dissolved materials throughout body Oxygen, carbon
dioxide, nutrients, waste Picks up waste products of cell
metabolism & takes to lungs and kidneys (to be expelled from
body)
Slide 4
The Heart Two major circulations Each has its own pump Both
pumps are incorporated into the heart Location Middle of chest,
behind sternum, within ribcage Pericardial cavity Above diaphragm
Structure Primarily a shell with four chambers inside
Slide 5
Blood Flow Two sides of heart are anatomically and functionally
separate pumping units Right side pumps blood through pulmonary
circulation Left side pumps blood through systemic circulation
Slide 6
Heart Facts Adult human heart approx size of closed fist About
5 inches long and 3 inches wide Weighs just less than 1 pound Beats
about 100,000 times each day Pump about 8,000 gallons of blood
through 12,000 miles of vessels each day Contracts and relaxes
70-80 bpm
Slide 7
Structure of Heart Four cavities Atria Form curved top of heart
Ventricles Meet at bottom of heart to form pointed base Points
toward left side of chest
Slide 8
Structure of Heart Left Side Right Side One ventricle One
atrium Mitral valveconnects left atrium to left ventricle One
ventricle One atrium Tricuspid valveconnects right atrium to right
ventricle Wall, septum, separates right and left sides
Slide 9
Aorta hearts main artery carries blood away from heart to bodys
cells Pulmonary artery artery that connects heart to lungs Two
largest veins: Superior vena cava Inferior vena cava
Slide 10
Circulation As heart contracts, it pushes blood though chambers
and into the vessels Nerves connected to the heart regulate the
speed of contractions Greater the activity, faster the heart will
pump; faster heart pumps, more oxygen and nutrient are carried
throughout body
Blood Only tissue that flows throughout body Carries oxygen
& nutrients to all parts of body and transports waste products
back to lungs, kidneys, and liver for disposal Essential part of
immune system Crucial for fluid and temperature balance Hydraulic
fluid for certain functions Highway for hormonal messages Composed
of plasma and billions of cells
Slide 13
Plasma The yellowish, liquid part of blood River in which blood
cells travel Makes up 55% of total volume Carries blood cells +
Nutrients (sugars, amino acids, fats, salts, minerals) Waste
products (CO2, lactic acid, urea) Antibodies Clotting proteins
(called clotting factors) Chemical messengers (hormones) Proteins
that help maintain bodys fluid balance
Slide 14
BloodRBCs & Hemoglobin Red Blood Cells (erythrocytes)
Highly specialized cells that have been stripped of everything,
including nucleus Major job: transporting oxygen Percentage of RBCs
in total blood volume called hematocrit Hemoglobin Special
red-colored molecule that fills RBCs Picks up oxygen in areas where
O2 is abundant and releases O2 in tissues where O2 concentration
lowest
Slide 15
BloodWhite Blood Cells 5 distinct kinds Neutrophils, monocytes,
lymphocytes, eosinophils, basophils Able to change according to
need and situation in body Can leave blood stream, sliding out
through vessel walls & attacking invaders at site of
infections
Slide 16
BloodPlatelets Fragments of much larger cell (megakaryocyte)
which stays in bone marrow after it differentiates and matures from
stem cell Platelets leave bone marrow & circulate throughout
the body When stimulated by substance from damaged tissue,
platelets release substance to help clot blood
Slide 17
Blood Vessels Hollow tubes running throughout the body 5 types
Arteries Arterioles Veins Venules Capillaries Provide 2
measurements: Pulse Blood pressure
Slide 18
Arteries Blood vessels that carry blood from the heart to
organs & cells Muscular walls that allow them to dilate or
constrict Arterioles: very small arteries Largest artery=aorta Runs
from chest into abdomen Receives blood directly from left
ventricle
Slide 19
Veins Blood vessels that carry blood back to heart Thinner wall
Contain numerous one-way valves (keep blood moving toward heart)
Deep veins in LE surrounded by large muscle groups; compress the
deep veins when muscles contract Contractions in extremities helps
propel blood toward heart; increase venous return
Slide 20
Veins Largest vein=superior & inferior vena cava Bring
blood from upper and lower body into right atrium Venules: smallest
veins
Slide 21
Slide 22
Capillaries Tiny, microscopic blood vessels that connect
arteries to veins Responsible for transferring oxygen and nutrients
to cells Wall so thin that O2 passes from arterial blood through
them into cells in organs/tissues Waste products (CO2) pass into
capillaries to be carried back by veins to heart/lungs
Slide 23
Coronary Arteries The hearts own system of blood vessels
Located around heart muscle to provide blood and oxygen to all
parts of heart Two primary coronary arteries branch off into
smaller vessels Right coronary artery: feeds right atrium &
ventricle and bottom of left ventricle Left main coronary artery:
supplies blood to rest of heart Left anterior descending
Circumflex
Slide 24
Hearts Conduction System Hearts electrical system Consisting of
specialized cells within heart muscle that carry an electrical
signal Regulates pumping of heart
Slide 25
Blood Pressure Heart pumps blood into arteries; surge of blood
filling vessels creates pressure against vessel walls Pressure
measured by 2 numbers: Systolic: highest pressure in heart
Correlates to ventricular ctx Average 120 mm/Hg Diastolic: lowest
pressure in heart Relates to ventricular ctx Average 80 mm/Hg Pulse
pressure: difference between diastolic and systolic pressures
Slide 26
Pulse Rhythmical beating of heart Created by alternating
expansion and contraction of artery as blood flows through 7 areas
where pulse can be felt Brachial artery Common carotid artery
Femoral artery Dorsalis pedis artery Popliteal artery Radial artery
Temporal artery
Slide 27
Target Heart Rate Percentage of the maximum heart rate that is
safe to reach during exercise AHA recommends 50-75% for average
healthy person Calculated 220-age THR is sliding scale that
decreases with age Tool for measuring cardiovascular exercise
Maintain THR for 15-30 min daily health benefits
Slide 28
Flow of Blood through Heart Superior/inferior vena cava Right
atrium Tricuspid valve Right ventricle Semi-lunar valve Pulmonary
artery Lungs http://www.nhlbi.nih.gov/health/dci/Disease
s/hhw/hhw_pumping.html
Slide 29
Flow of Blood through Heart Back to heart via pulmonary vein
Left atrium Bicuspid valve Left ventricle Semi-lunar valve Aorta
Organs in the body