Chapter Five Flashcards
The circulatory system transports materials throughout the body
Functions of the blood
- Transport
- Regulation
- Protection
Transport
Transports nutrients and oxygen to the tissues and removes waste such as carbon dioxide
Regulation
Assists in maintaining the body’s pH level and temperature
Protection
- Prevent blood loss if blood vessels are damaged
- Protects the body against pathogens and toxins
Red blood cells
- Life span of 120 days
- No nucleus to save space for carrying oxygen and going through narrow spaces (capillaries)
- Haemoglobin is present to attach to oxygen
White blood cells
- Fights infections and foreign substances by engulfing and destroying them
- Contains a nucleus
-Shape varies to squeeze between cells in tissues
Platelets
Irregular shape to help in clotting blood to stop bleeding
Blood plasma
A clear pale yellow liquid which comprises of 46-63% of the whole blood
What does blood plasma consist of
- Water (92%)
- Dissolved molecules (1%)
- Dissolved plasma proteins (7%)
Oxygen transport
- 3% dissolved in plasma as a solution
- 97% combined with haemoglobin in RBCs
What colour is oxyhaemoglobin
Bright red
Carbon dioxide transport
- 8% dissolved in plasma as a solution
- 22% combined with haemoglobin as carbaminohaemoglobin
- 70% in plasma as bicarbonate ions
Blood clotting steps
- Vasoconstriction
- Platelet plug
- Coagulation
Blood clotting
The events that take place to minimise blood loss and prevent entry of infecting micro organisms
Vasoconstriction
Muscles in the walls of the small arteries that are injured/broken constrict to reduce blood flow and therefore blood loss
Platelet plug
- Walls of arteries are normally smooth but become rough with injury that allow platelets to stick
- Platelets build up at the sight to form a plug
- Reduces blood loss
- Platelets release substances that act as vasoconstrictors and prolong constriction of the damaged vessels
Coagulation
- Complex process involving a large number of chemical substances present in the blood plasma
- Formation of threads occur called fibrin which form mesh that traps blood cells, platelets and plasma
- This mesh with its trapped material holds the clot in position
Clot retraction
- Network of threads become denser and stronger pulling damaged blood vessels together
- As clot retraction occurs, fluid (serum) is squeezed out
- The clot dries forming a scab preventing infection
Common name for Thrombocytes
Platelets
Common name for Leucocytes
White blood cells
Common name for Erythrocytes
Red blood cells
Coagulation is
Blood clotting
Arteries
- Thick walled
- Muscular
- Carry blood away from heart to the organs and tissues
- Oxygenated blood
- No valves
Veins
- Thin walled
- Carry blood back to the heart away from the organs and tissues
- Deoxygenated blood
- Valves
Capillaries
- Very thin walls (one cell thick)
- Allows materials to pass from blood to cells and cells to blood
What are blood vessels importance
- Facilitate the transport of materials to and from exchange surfaces
- Provides efficient distribution and collection of the blood in the body
Valves
- Control the direction of blood flow (no backwards flow of blood)
- Held in position by strong tendons
Arterioles
Subunits of arteries in the tissues
Venules
Subunits of veins in the tissues
Sinoatrial node
- On the outside walls on the right side of the heart
- Peace maker (sets rhythm)
- Can be overridden in the brain
Diseases effecting circulatory system
- Heart attack
- Hypertension
- Angina
- Artenosclerosis
- Stroke
- Peripheral vascular disease
Blood clumping is the result of
Mixing blood types
What is the difference between blood groups
The presence or absence of certain protein molecules called antibodies and antigens
Where are antibodies found
In the blood plasma
where are antigens found
On the surface of the red blood cells
The four different blood types are
- A
- B
- AB
- O
Blood group A
- A antigens on the surface of the RBCs
- B antibodies in the blood plasma
Blood group B
- B antigens on the surface of the RBCs
- A antibodies in the blood plasma
Blood group AB
- Both A and B antigens on the surface of the RBCs
- No antibodies in blood plasma
Blood group O
- Neither A nor B antigens on the surface of RBCs
- Both A and B antibodies in blood plasma
Rhesus factor
- Rh antigen
- If antigens are present blood is Rh+, if absent Rh-
What is agglutination
When RBCs carrying one or both antigens are exposed to the corresponding antibodies and the blood clumps
Which blood type is known as the universal donor
O
Which blood type is known as the universal reciever
AB
Blood transfusion types
- Whole blood
- Platelet concentrations
- Red cell concentration
- Cryoprecipitate
- Autologous transfusion
- Immunoglobins
Whole blood transfusion
- Blood is taken from a donor with a chemical added to prevent blood clotting
- Used for severe blood loss
Red cell concentration
- Blood is spun, heavier cells sink to the bottom leaving the plasma on top, WBCs and platelets may or may not be removed
- Used for patients suffering from heart disease or anemia
Platelet concentration
Given to patients with abnormal platelets or a reduced number of them
Cryoprecipitate
- Plasma is frozen and thawed slowly, plasma is a liquid but cryoprecipitate remains solid
- Treats forms of haemophilia
Autologous transfusion
- Patient’s own blood is used
- Blood is collected prior to operation
- Eliminated risk of transmission of diseases
Immunoglobins
- Groups of proteins that act as antibodies
- Extracted from the blood
- Used for those who are deficient in antibodies
Lymphatic system
- Aids the immune system in removing and destroying waste, debris, dead blood cells, pathogens, toxins and cancer cells
- Absorbs fat and fat soluble vitamins from the digestive system and delivers the nutrients to the cells
- Removes excess fluid and waste products from the interstitial spaces between cells
Interstitial fluid
Delivers nourishing products to the cells and when it leaves it removes waste, afterwards 90% is taken back to the circulatory system as venous blood and the other 10% stays behind as lymph in the tissues
Lymph
- Moved through the body through its own vessels
- One-way from the interstitial spaces to the veins at the base of the neck
- Depends on the motions of the muscles and joint pumps
Lymph nodes
- Large particles are trapped in the network of fibres
- Large phagocytes called macrophages engulf and destroy these particles
- when infections occur more lymphocytes and macrophages are formed and lymph nodes become swollen
Flow of blood through the right side of the heart
- Superior and inferior vena cava
- Right atrium
- Tricuspid atrioventricular valve
- Right ventricle
- Pulmonic semilunar valve
- Pulmonary artery
Flow of blood through the left side of the heart
- Pulmonary Veins
- Left atrium
- Bicuspid atrioventricular valve
- Left ventricle
- Aortic semilunar valve
- Aorta
Cardiac cycle
The events that occur in one complete beat of the heart
Systole
The phase of the cardiac cycle when the heart muscle contracts
Diastole
The filling phase of the cardiac cycle
Atrioventricular valves
Valves within the heart that ensure that blood flows through it in one direction only
Atria
The top chambers of the heart, single: atrium
Cardiac muscle
The muscle that forms the walls of the heart
Double circulation system
A circulatory system in which the blood passes through the heart twice and has two different circuits
Inflammation
A condition where a part of the body become reddened, swollen, hot and often painful, normally a reaction to injury or infection
Lumen
The central cavity of a tubular or other hollow structure in an organism or cell
Ventricle
The lower chambers of the heart
Carbaminohaemoglobin
A molecule resulting from a combination of carbon dioxideand haemoglobin
Fibrinogen
A solublle protein present in the bloods plasma
Haemorrhage
The escape of blood from a ruptures blood vessel
Why is blood considered a connective tissue
It has a matrix
Pulmonary Veins
Veins that carry oxygenated blood towards the heart
Pulmonary artery
The artery that carries deoxygenated blood away from the heart
What are the tendons in the heart called
Chordae tendineae
What are ABO antigens
Sugars
What are rhesus antigens
Proteins
How is lymph moved through the body
As a result of smooth muscle, skeletal muscle and valves, the smooth layer of muscles surrounding the vessels are able to contract providing additional force
Lymph capillaries
- Slightly larger than blood capillaries
- More permeable
- Have valves
Lymph nodes
- Bean shaped in length from 1mm-25mm
- Within the framework masses of lymphoid tissue, containing cells known as lymphocytes, macrophages and plasma cells
