animals: circulation - university of texas at austin circulation blood is the transport medium of...
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Animals: Circulation
Blood is the transport medium of the circulatory system
Outline
1. Key Concepts
2. Circulatory system basics
3. Types of circulatory systems
4. Components of blood
5. Human circulatory system
6. Lymphatic system
7. Conclusions
Key Concepts:1.All cells survive by exchanging
substances with their surroundings
2.Blood is the transport medium of the circulatory system
3.There are two types of circulatory systems (open and closed)
4.The lymphatic system has three functions1. Drainage 2.Absorption 3.Delivery of pathogens
Circulatory, Respiratory, and Digestive Systems
circulatory system basics
1. A fluid-blood: as a medium of transport
2. A system of channels – blood vessels: conduct the blood throughout the body
3. A pump – the heart: keep the blood circulation
Types of circulatory systems
1. Open circulatory systems- blood not always in vessels- insects, spiders
2. Closed circulatory systems- blood always in vessels- earthworm, vertebrates
Flow Through an Open Circulatory System
Grasshopper
Flow Through a Closed Circulatory System
Earthworm
Closed Circulatory Systems of Vertebrates
Fish Amphibian
Closed Circulatory Systems of Vertebrates
Birds and Mammals
Components of bloodPlasma > 50%
Water 91-92 %
Protein 7-8 %
Ions, sugars, amino acids, hormones, vitamins, and gases 1-2 %
Cellular portion (Blood Cells) 40-50%Red blood cells 5.4 million/ul
White blood cells 5,000 - 10,000
Platelets 250,000 - 300,000
The Cellular Componentsof Blood
Red Blood Cells
The Cellular Componentsof Blood
plasma
cells,platelets
Components Relative Amounts Functions
Plasma Portion (50%–60% of total volume):
1. water
2. Plasma proteins (albumin, globulins,Fibrinogens, etc.)
3. Ions, sugars, lipids, amino acids,hormones, vitamins, dissolved gases
91%–92% ofplasma volume
7%–8%
1%–2%
Solvent
Defense, clotting, lipid transport,roles in extracellular fluid volume, etc.
Roles in extracellular fluid volume, pH, etc.
Cellular Portion (40%–50% of total volume):
1. Red blood cells
2. White blood cells:NeutrophilsLymphocytesMonocytes (macrophages)EosinophilsBasophils
3. Platelets
4,800,000–5,400,000per microliter
3,000–6,7501,000–2,700150–720100–36025–90
250,000–300,000
Oxygen, carbon dioxide transport
Phagocytosis during inflammationImmune responsesPhagocytosis in all defense responsesDefense against parasitic wormsSecrete substances for inflammatoryresponse and for fat removal from blood
Roles in clotting
blood
Bone Marrow
Aging
Human circulatory system
I. FunctionsII. Blood VesselsIII. The HeartIV. Heart SoundsV. Blood PressureVI. Human Blood types
Human circulatory system
Human circulatory systemFunctions
1. Transport of O2 and CO22. Distribution of nutrients3. Transport of waste ( liver kidney excretion)4. Distribution of hormones5. Regulation of body temperature6. Protection of the body against
blood loss and disease
Human circulatory system (Blood Vessels)
Arteries and Arteriolesa. Thick walls, smooth muscle with elastic tissue to
withstand high pressureb. Carry blood away from the heart
Capillariesa. Tiniest vessels; thin, single-cell thick for easy diffusionb. Exchange of materials between blood and body cells
Venules and Veinsa. One-way valves in thin-walled vessels surrounded by
thin layer of smooth muscle giving low resistance to blood flow, which is assisted by skeletal muscle
b. Returns blood to the heart
Structure of Blood Vessels
Arteries Veins
Veins
VeinsLarge diameter
Low resistance
Valves
One-way flow
Blood Reservoir
50-60% or total
blood volume
Human circulatory system (The Heart)
1. Two types of chambersA. Atria (Atrium) – receiving chambersB. Ventricles – pumping chambers arteries
2. Mammals and birds – 2 halves of heart (separated)- each half = atrium + ventricle
One circuit (pulmonary circuit) –pick up O2 R V lungs L A L V
2nd circuit (Systemic circuit) – deliver nutrients, O2, etc.L V body tissue R A R V
Human pulmonary circuit
2 circuitsPulmonary
Systemic
Systemic Circuit for Blood Flow
The Human Heart
Human circulatory system (The Heart)
Pacemaker – a region of cells that generate electrical signals, heart contracts. = Sinoatrial node (SA node)
SA node sends signal to walls of atria (to contract) it also sends signal to another node AV node (atrioventricular node). Then AV node sends signal to ventricle muscles ventricles contract.
Cardiac Conducting System
SA nodePacemaker
AV node
AV bundle
Human circulatory system(Heart Sounds)
Cardiac output = 5-6 l /min (sports 30-35 l / min)60-80 contraction/min
First sound “Lubb” = closing of valves between atria and ventricles.
Second sound “Dubb” = closing of valves between ventricles and arteries.
Systole = period of contraction of heart ventricles, begins with “Lubb’ sound.
Diastole = period of relaxation of heart ventricles, begins with “Dubb” sound.
Cardiac Cycle
Systole
Diastole
Closure/Opening of valves
Contraction of ventricles is the
force for blood flow
Human circulatory system(B.P.)Pressure = force/unit areaBlood pressure (B. P.) = pressure of blood on
walls of vessels.Young adult: Systolic B. P. 120 mmHgYoung adult: Diastolic B. P. 80 mmHg
(millimeters of mercury)50,000 miles of human capillaries, only 30-50%
capillaries open. No closure of capillaries to brain & heart.wt. in kg x 8% = # l blood, 1 lb = 0.45 kg165 lb = 75 kg x 8% = 6 l blood
Blood Pressure
Systolic
Diastolic
Blood Pressure
Systolic
Diastolic
Fig. 39.21, p. 682
narrowedlumen ofartery
cholesteroland fatdeposits
endothelium
lumen of artery
Blood TypingHuman Blood types
a single gene located on chromosome 9(4 types: A, B, AB, O)
Based on markers on red blood cells
[Blood Type]
1. A (AA, Ao) anti B antibodies
2. B (BB, Bo) anti A antibodies
3. AB (AB) none
4. O (oo) anti A and anti B antibodies
Lymphatic SystemLymphatic System - supplement to vertebrate circulatory
system. It runs parallel to venous half of circulatory system.
1. Structurea. complex network of thin-walled vessels and two
organs (thymus and spleen both produce lymphocytes)
b. in proximity to the capillary networkc. composed of cells with openings between them that
act as one-way valves2. Components of lymphatic fluid (lymph):
a. water b. white blood cells c. foreign matter
Lymphatic System3. Lymph flow comes from the contraction of
nearby muscles (walking, breathing, etc.)4. Functions
a. Remove of excess body tissue fluidsb. Transport of fats from the small intestine to blood (absorption)c. Defense of the body by exposing viruses, bacteria, and cancer cells to white blood cells
(sites = lymphatic nodes)
Lymphatic System
1. Lymph vessels and capillaries
2. Functions1. Drainage
2. Absorption
3. Delivery of pathogens
Lymphatic System
Lymphatic System
In Conclusion
1. Circulatory systems consist of a heart, blood vessels, and blood
2. Blood helps maintain favorable conditions for cells
3. The human heart is a double pump
4. The heart’s partition separates blood flow into two circuits, the pulmonary and the other systemic
In Conclusion
5. Ventricular contraction drives the blood through both circuits
6. The cardiac conduction system serves as the basis for the heart’s rhythmic, spontaneous contractions
7. The lymphatic system has three functions