The Circulatory System Flashcards
What is the function of the circulatory system (transport system)
Carry nutrients to cells / waste away
Transport hormones/enzymes from cells in one part of body to another
Allow transport of immune cells throughout body
What makes up the circulatory system
Blood vessel
Heart (brain of the system)
Blood
Open circulatory system
Blood carrying oxygen/nutrients is pumped into the body cavities where it baths the cells directly
Low pressure system
Closed circulatory system
Blood carrying oxygen/nutrients is always contained within blood vessels
High pressure system
How many liters of blood does the average person contain ?
70kg contains 5L of blood
In those 5L, 55% is plasma and 45% is formed solid cells
Erythrocytes (RBC)
Transport oxygen and contain hemoglobin (respiratory pigment molecule that increases RBC ability to carry oxygen)
280M hemoglobin found in 1 RBC
Hemoglobin contains a Heme group ( _____ containing pigment that actually binds to oxygen) and a globin (a _______ protein structure)
Hemoglobin contains a Heme group (iron containing pigment that actually binds to oxygen) and a globin (a globular protein structure)
How many iron molecules can attach to 1 hemoglobin molecule
4 iron molecules can attach to 1 haemoglobin molecule
Each iron molecule can carry 1 oxygen molecule
1 hemoglobin molecule can carry how many oxygen molecules?
4 oxygen molecules
Describe the difficulty of the first oxygen molecule binding when no binding sites are occupied by oxygen and how it changes after the first heme group is occupied.
When no binding sites are occupied by oxygen, it is difficult for the first oxygen molecule to bind. However, after the first heme group is occupied, subsequent oxygen binding becomes easier.
Life span of RBC
Is 120 days
Is the blood of elderly people older then the blood of younger people?
No, since blood cells are constantly replenished, so blood age remains relatively consistent regardless of a person’s age.
When the RBC is mature, it does not contain a nucleus. WHY?
To make more space for oxygen-carrying hemoglobin molecules
Where are RBC produced
Red bone marrow
Leukocytes (white blood cells)
Contain a nucleus
Produced in red bone marrow
The life span is 7-10 days
What is the function of leukocytes
kill invading microbes by phagocytosis (eat) . Once the microbe has been engulfed, the leukocyte releases
enzymes that digest the microbe and the leukocyte itself
Platelets
Don’t contain nucleus
Produced in red bone marrow
They aren’t cells, there are fragments of cell that were created when larger cells in the bon marrow broke apart
Function and life span of platelets
Break down easily in blood (life span 7-10 days)
Function in blood clotting = prevent excessive blood loss
Your blood does not clot until a blood vessel is broken, which indicates that the first step is triggered by injury
Formation on blood clot (detailed)
- Blood does not clot until the blood vessel is broken = indicates that the first step is triggered by injury
- Substances are released from the broken blood vessel (chemicals called PF3’s)
- The chemicals (PF3’s) attract platelets to the site
- As the platelets collect, they rupture and release other chemicals called thromboplastin
- Thromboplastin reacts with prothrombin (protein produced by the liver) with the help of Calcium ions which catalyze the reaction
- Thromboplastin + Prothrombin ➡️CA2
Thrombin - Thrombin reacts with fibrinogen (plasma protein) = fibrin
- Fibrin is an insoluble material that forms a mesh of strands around the area of injury
9.This mesh prevents the loss of blood and eventually solidifies to form a clot
Formation of blood clot (simple)
- Blood vessel ruptures and releases chemical called PF3’s
- PF3’s attract platelets to the site
- Platelets release thromboplastin
- Thromboplastin react with Prothrombin to produce Thrombin. This reaction is catalyzed by Calcium ions
- Thrombin reacts with Fibrinogen to produce Fibrin
- Fibrin forms a mesh that prevents blood loss
What are the 4 major blood groups
A, B, AB, O
Each blood group is characterized by the presence/absence of particular protein markers on the walls of RBC
The four blood groups results from different combinations of two protein markers (___and ___)
The four blood groups results from different combinations of two protein markers (A and B)
What are the proteins that stimulate the formation of antibodies
Antigens are proteins that stimulates the formation of antibodies
what are the proteins in blood plasma that react with antigens?
Antibodies (proteins in blood plasma that react with antigens)
People who have Type A blood have the ___ antigen attach to their RBC membrane and have Antibody ___ in plasma
People who have Type A blood have the A antigen attache to their RBC membrane and have Antibody B in plasma
People with Type B blood have the ___ antigens attached to their RBC membrane and have Antibody ___ in plasma
People with Type B blood have the B antigens attached to their RBC membrane and have Antibody A in plasma
People with AB blood have ___ antigens attached to their RBC membrane and have neither Antibody ___ or ___
People with AB blood have AB antigens attached to their RBC membrane and have neither Antibody A or B
People with O blood have ____ antigens attached to their RBC membrane, but have Antibody ___ and ___.
People with O blood have NO antigens attached to their RBC membrane, but have Antibody A and B.
Can only accept blood from O type donor.
How does the body react when different markers (antigens) enter the blood and what is the role of white blood cells in this process?
When markers (antigens) that are different enter the blood, the body identifies them as though they are invading microbes. The body‛s white blood cells will destroy the invading antigens
The transport vessels (3 main types of blood vessels)
Arteries
Veins
Capillaries
Arteries
Carry blood AWAY from the heart
Have thick walls
1. Connective tissue (outer most layer)
2. Smooth muscle(thickest/middle layer)
3. Smooth epithelial cells (1 cell thick, reduce friction from blood, inner layer)
Strong walls make arteries capable of withstanding great __________.
Every time your heart contracts, blood surges from your heart and enters the arteries, forcing the arteries to _______. When the heart relaxes, the arteries _________.
Strong walls make arteries capable of withstanding great pressure
Every time your heart contracts, blood surges from your heart and enters the arteries, forcing the arteries to stretch. When the heart relaxes, the arteries recoil
What is a pulse?
Change in diameter of arteries after heart contacts blood surges through the arteries
Aorta (parts)
- Ascending aorta
- Aortic arch
- Thoracic aorta
- Abdominal aorta
Descending aorta = 3+4
Artery disorders
Atherosclerosis
Carotid Artery Disease
Aneurysms
Raynaud’s Syndrome
Atherosclerosis = fat in arteries
Plaque (fat) blockage in arteries anywhere in body
Build up takes a while
Narrows diameter of artery causing INCREASE in blood pressure
Carotid artery disease
Blockage in carotid artery
Artery in neck (supply blood to brain) becomes clogged and may cause stroke
Atherosclerosis treatments
- Angioplasty (inflated balloon squeezing fat build up) - non permanent
- Stenting ( mesh stent that opens up/expands the artery)
- Endarterectomy ( surgically removing the build up from artery)