human form and function (01) Flashcards
What are respiratory pigments?
Respiratory pigments are organic compounds which can combine with oxygen where the partial pressure of oxygen is high, and release oxygen where the partial pressure of oxygen is low
What is the function of respiratory pigments
They can combine with oxygen where the partial pressure of oxygen is high, and release oxygen where the partial pressure of oxygen is low
Why has the transportation of blood become a problem for complex animals?
Since oxygen is less soluble in watery mediums including blood, transportation of oxygen from the respiratory surface to the tissues/organs is a problem
How have complex animals overcome the problem of transportation of blood?
By evolving respiratory pigments
Write examples for different respiratory pigments that can be seen in the animal kingdom
Haemoglobin
Haemocyanin
Chlorocruorin
Haemoerythrin
Myogoblin
Write the location of haemoglobin
It is present in the blood of humans, vertebrates and annelids
Write the location of haemocyanin
It’s present in the hemolymph of arthropods and molluscs
Write the location of chlorocruorin
It’s present in the blood of many annelids
Write the location of haemoerythrin
It’s present in the blood of marine invertebrates (some annelids)
Write the location of myoglobin
present in vertebrae muscle tissues
Write the functions of hemoglobin, hemocyanin, chlorocruorin, and haemoerythrin
Transportation of oxygen from the respiratory surfaces to the tissues/organs while transporting carbon dioxide from tissues/organs to the respiratory surface for elimination
Write the function of myoglobin
Oxygen storage
What molecules is responsible for the transport of oxygen around the body?
Haemoglobin molecule
Describe the nature of a hemoglobin molecule
Hemoglobin is composed of 4 subunits
Each subunit is composed of a globin protein and the haem group
A ferrous (iron) atom is located within each haem group and each of these can combine reversibly with one molecule of oxygen to form oxyhemoglobin
So, each hemoglobin molecule can carry upto 4 oxygen molecules
What are haem groups responsible for?
The characteristic red colour of the blood
What is the function of the ferrous (iron) atom within each haem group?
Each of these can combine reversibly with one molecule of oxygen
How many oxygen molecules can each hemoglobin molecule carry?
4
Write the chemical equations for the combination of oxygen with hemoglobin to form oxyhemoglobin
Hb + 4O2 ————-> HbO8
(Hemoglobin molecules) <———— Oxyhemoglobin
What are the ways CO2 is transported?
As HCO3- ions in the plasma
As carbaminohemoglobin
Dissolved in the plasma
What % of CO2 is transported as HCO3- ions in the plasma?
about 70%
What % of CO2 is transported as carbaminohemoglobin?
about 23%
What % of CO2 is transported dissolved in the plasma?
about 7%
Describe how carbon dioxide ions transport as HCO3- ions in the plasma
When CO2 diffuses into red blood cells, the enzyme carbonic anhydrase catalyzed the combination of CO2 with water to form HCO3- and H+ ions
What is the function of the enzyme carbonic anhydrase in transporting HCO3- ions in the plasma
When CO2 diffuses into red blood cells, the enzyme carbonic anhydrase catalyzed the combination of CO2 with water to form HCO3- and H+ ions
How does the HCO3- ions move out?
The HCO3- moves out of the erythrocytes into the plasma
How does CO2 transport as carbaminohemoglobin?
CO2 combines with the protein group of hemoglobin and forms carbaminohemoglobin
Why does CO2 not compete with the oxygen binding sites in hemoglobin?
Because CO2 combines with the protein group of hemoglobin to form carbaminohemoglobin
How is CO2 transported while dissolved in plasma?
as free gas
What is blood?
Blood is a connective tissue composed of cells and plasma
What is blood composed of?
cells
plasma
Where are red blood cells, leukocytes and platelets developed from?
From the bone marrow in the bones such as
ribs
pelvis
sternum
vertebrae
Where is erythropoietin hormone from?
the kidneys
What does erythropoietin hormone stimulate?
It stimulates the generation of red blood cells
What are the 3 types of cellular components of blood
Red Blood Cells
White Blood Cells
Platelets
Write the features of a red blood cell
Small
Bi-concave
Disk-like cells
What organelles do RBC lack
Mature erythrocytes lack nuclei
Mitochondria
Why do mature erythrocytes lack nuclei?
This character helps transport more hemoglobin molecules within the cell.
Why do RBC lack mitochondria?
Because they lack mitochondria, they produce ATP via anaerobic respiration.
If they produce ATP via aerobic respiration, that will reduce the oxygen transport efficiency
What is the life span of a red blood cell?
120 days
How many RBCs are found in a microliter of blood
4-6 million RBC (this figure can vary depending on the gender and health status)
Write the main functions of RBC
Transportation of oxygen and carbon dioxide molecules
What are the 5 types of leukocytes?
Monocytes
Lymphocytes
Neutrophils
Eosinophils
Basophils
Write the functions of WBC
Body defense
Phagocytic engulfing
Digesting microorganisms
They develop into T cells and B cells which increase the immune response against foreign substances
Write the reason WBC develop into T cells and B cells?
to increase the immune response against foreign substances
Where are platelets derived from?
Bone marrow cells
What feature don’t platelets have?
Nuclei
Write the major function of platelets
Blood clotting
What does blood plasma consist of?
Water
Nutrients
Hormones
Metabolic Wastes
Respiratory Gases
Inorganic ions in dissolved forms
Plasma Proteins (such as Albumin)
Antibodies and fibrinogen
What is the pH of human blood
Around 7.4
What is the protein concentration of plasma higher than?
Interstitial fluid
Write the functions of the components of blood plasma
The dissolved ions in the plasma buffers and maintains the osmotic balance of blood
Albumin in the plasma buffers the blood
Antibodies are involved in defense
Fibrinogen in plasma aids in blood clotting
Write the function of the dissolved ions in the plasma
The dissolved ions in the plasma buffers and maintains the osmotic balance of blood
Write the function of the albumin in the plasma
Buffers the blood
Write the function of the antibodies in the plasma
They’re involved in defense
Write the function of fibrinogen in plasma
Aids in blood clotting
What is serum?
When clotting factors are removed from the plasma, it is called serum.
When clotting factors are removed from the plasma, what is it called?
Serum
Write the major functions of blood
Defense against foreign invasions
Aids in osmoregulation
Transporting nutrients
Transporting oxygen to organs and removing carbon dioxide from tissues and organs
Transporting soluble excretory materials to organs of excretion
Transporting hormones from the glands where they are produced to target organs
What is a blood clot?
When a tissue is damaged, blood flows from it ad coagulates to form a blood clot
Write the functions of a blood clot
This prevents further blood loss
Prevents the entry of pathogenic microorganisms which is of clear survival value
Describe the reactions that take place in order for coagulation to occur
A highly complex series of reactions take place
A cascade reaction
Describe how a blood clot is formed.
When the blood vessel is damaged, the connective tissues of the vessel wall is exposed.
So, the platelets in blood adhere to the collagen fibers of the connective tissue and release substances that make the nearby platelets sticky
This platelet plug provides instant protection against blood loss
Then, platelets release clotting factors.
Clotting factors trigger the formation of thrombin.
Thrombin converts fibrinogen to fibrin
Next, this fibrin aggregates into threads that forms a network of the clot
The activated thrombin is also involved in forming more thrombin which completes the formation of the blood clot.
How is a platelet plug formed?
When the blood vessel is damaged, the connective tissues of the vessel wall is exposed.
So, the platelets in blood adhere to the collagen fibers of the connective tissue and release substances that make the nearby platelets sticky
Write the functions of a platelet plug
This platelet plug provides instant protection against blood loss
Write the function of clotting factors
Clotting factors trigger the formation of thrombin.
Write the function of thrombin
Thrombin converts fibrinogen to fibrin
The activated thrombin is also involved in forming more thrombin which completes the formation of the blood clot.
Write the function of fibrin
fibrin aggregates into threads that forms a network of the clot
Where can clotting factors be found?
Platelets
Damaged Cells
Plasma
Give examples for clotting factors
Calcium
Vitamin K
Why does the blood in undamaged vessels not clot?
Because the vessel’s lining is very smooth and does not promote platelet aggregation or cell rupture
Some substances like heparin prevents clotting.
Heparin prevents the conversion of prothrombin into thrombin and fibrinogen into fibrin and is widely used as an anticoagulant clinically.
Write the function of heparin
Some substances like heparin prevents clotting.
Heparin prevents the conversion of prothrombin into thrombin and fibrinogen into fibrin and is widely used as an anticoagulant clinically.
Where is heparin used?
It is widely used clinically as an anticoagulant
What are agglutinogen?
The surface of blood contains antigens called agglutinogens
What are the 2 antigens/agglutinogens
Antigen A
Antigen B
What are the 2 antibodies?
Anti- A / Antibody a
Anti-B / Antibody b
How is the ABO blood group system originated?
The surface of blood cells carries antigens called agglutinogens. In addition, individuals have antibodies in the plasma.
A person with a specific antigen in red cells do no possess the corresponding antibody in the plasma
ex: anyone with antigen A in the blood cell membrane has no anti-A antibody in the plasma.
This concept is used to originate the ABO blood grouping system
According to the ABO blood group system, what are the 4 blood groups?
A
B
AB
O
How is blood group A defined?
If the red blood cells of a person has antigen A and plasma has antibodies b (Anti-B) then that person’s blood group is A
How is blood group B defined?
If the red blood cells of a person has antigen B and the plasma has antibodies a (Anti-A), then that person’s blood group is B
How is blood group AB defined?
If the red blood cells of a person has both antigen A and B and the plasma has no anti-A or anti-B, then that person’s blood group is AB
How is blood group O defined?
If the red blood cells of a person has neither antigen A or B but the plasma has both antibodies a and b (Anti-A and Anti-B) then that person’s blood group is O
What are the conditions in blood transfusion?
In blood transfusion, it is vital that they receive blood that is compatible with their own
It is important to know the blood groups of the donor and recipient
Prior to transfusion, cross-matching is still required to ensure that there is no reaction between donor and recipient blood.
Write a vital factor in blood transfusion
In blood transfusion, it is vital that they receive blood that is compatible with their own
Why is it vital that they receive blood that is compatible with their own in blood transfusion?
If its incompatible a type of immune response occurs.
This is because the donor’s RBC membranes possess a glycoprotein which act as antigens and react with antibodies (agglutinin) in the recipient’s plasma
The result is that the donor’s cells are agglutinated
Why does a type of immune response occur when people receive blood that is compatible with their own in blood transfusion?
This is because the donor’s RBC membranes possess a glycoprotein which act as antigens and react with antibodies (agglutinin) in the recipient’s plasma
The result is that the donor’s cells are agglutinated
When a blood transfusion occurs, why is it important to know the blood groups of the donor and recipient?
If its incompatible a type of immune response occurs.
This is because the donor’s RBC membranes possess a glycoprotein which act as antigens and react with antibodies (agglutinin) in the recipient’s plasma
The result is that the donor’s cells are agglutinated
Why are people with blood group AB called “universal recipients”?
People with blood group AB make neither anti-A or anti-B antibodies.
Transfusion of type A,B,AB, and O blood into these individuals is likely to be safe since there are no antibodies to react with them.
So, they’re called universal recipients.
Why are people with blood group O called “universal donors”?
An individual with blood group O has neither antigen A or antigen B in the plasma membrane of red blood cells. But they do have both antibodies (anti-A and anti-B) in their plasma
So individuals having blood group O can donate blood to people with any blood group
So, they’re called universal donors.
What must be required prior to blood transfusion?
Prior to transfusion, cross-matching is still required to ensure that there is no reaction between donor and recipient blood.
