Blood and Blood Group Questions in English

(C) Arnold $J$. Quick was an American physician and chemist who is best known for his work on blood coagulation. He developed the 'Quick's test' for prothrombin time. His research significantly contributed to the understanding of the role of Vitamin $K$ in the synthesis of prothrombin in the liver,which is essential for blood clotting.

(D) Vitamin $K$ is a fat-soluble vitamin that plays a crucial role in the process of blood coagulation.
It acts as a cofactor for the enzyme gamma-glutamyl carboxylase,which is responsible for the carboxylation of specific glutamic acid residues in several clotting factors,including prothrombin (Factor $II$),Factor $VII$,Factor $IX$,and Factor $X$.
Therefore,a deficiency of vitamin $K$ leads to an impaired synthesis of these clotting factors,most notably resulting in a significant reduction in the levels of functional prothrombin in the blood,which increases the time required for blood to clot.

(C) Vitamin $K$ is a fat-soluble vitamin that plays a crucial role in the synthesis of proteins required for blood coagulation (clotting).
Specifically,it acts as a cofactor for the enzyme gamma-glutamyl carboxylase,which modifies clotting factors $II$ (prothrombin),$VII$,$IX$,and $X$ in the liver.
Without vitamin $K$,the blood would not be able to clot properly,leading to excessive bleeding.

(C) The correct answer is $C$.
Vitamin $B_{12}$,also known as cyanocobalamin,is an essential water-soluble vitamin.
It plays a critical role in $DNA$ synthesis and the maturation of erythrocytes (red blood cells) in the bone marrow.
$A$ deficiency of Vitamin $B_{12}$ leads to megaloblastic anemia,where immature,large,and dysfunctional red blood cells are produced.

(B) Blood clotting (coagulation) is a complex process involving a cascade of clotting factors.
$1$. Vitamin $K$ is essential for the synthesis of several clotting factors in the liver,such as factors $II$ (prothrombin),$VII$,$IX$,and $X$.
$2$. Calcium ions $(Ca^{++})$ act as a crucial cofactor in multiple steps of the coagulation cascade,including the conversion of prothrombin to thrombin and the polymerization of fibrinogen into fibrin.
Therefore,both $Ca^{++}$ and Vitamin $K$ are necessary for the blood-clotting process.

(A) Cyanocobalamine is also known as Vitamin $B_{12}$.
It acts as a coenzyme in the synthesis of $DNA$ and is crucial for the maturation of red blood cells $(RBCs)$.
$A$ deficiency of Vitamin $B_{12}$ leads to pernicious anemia,which is characterized by the production of immature and abnormally large red blood cells.

(B) The correct answer is $B$.
Immature nucleated $RBCs$ (erythroblasts) in the blood indicate a failure in the maturation process of erythrocytes.
Vitamin $B_{12}$ (cyanocobalamin) and folic acid are essential co-factors for $DNA$ synthesis and cell division during erythropoiesis in the bone marrow.
$A$ deficiency in these vitamins leads to megaloblastic anaemia,where $RBCs$ remain immature and nucleated.
Therefore,supplementation with vitamin $B_{12}$ and folic acid is necessary to promote the maturation of these cells.

(C) Vitamin $K$ is essential for the synthesis of clotting factors in the liver,such as prothrombin and factors $VII, IX,$ and $X$.
These factors are necessary for the blood coagulation process.
Therefore,a deficiency of Vitamin $K$ prevents the blood from clotting effectively,leading to prolonged or continuous bleeding from an injured part of the body.

(D) The liver is responsible for synthesizing most plasma proteins,including fibrinogen,albumin,and prothrombin,which are essential for blood clotting and maintaining osmotic pressure.
Gamma globulins (immunoglobulins) are antibodies produced by plasma cells,which are derived from $B$-lymphocytes found in the lymph nodes,spleen,and other lymphoid tissues. Therefore,the liver does not synthesize gamma globulins.

(D) buffer system consists of a weak acid and its conjugate base,which helps maintain the $pH$ of the blood within a narrow range $(7.35-7.45)$.
In human blood,the bicarbonate buffer system is the most significant.
It consists of carbonic acid $(H_2CO_3)$ and its conjugate base,the bicarbonate ion $(HCO_3^-)$,often represented as a system involving sodium bicarbonate $(NaHCO_3)$ and carbonic acid $(H_2CO_3)$.
This system effectively neutralizes excess acids or bases to prevent drastic changes in blood $pH$.

(A) The $pH$ of human blood is maintained in a narrow range between $7.35$ and $7.45$.
This range is considered slightly alkaline (basic).
This specific $pH$ level is crucial for the optimal functioning of hemoglobin in binding and releasing $O_2$ and for the efficient transport of $CO_2$ in the form of bicarbonate ions $(HCO_3^-)$ within the plasma.

(A) Haemoglobin is an iron-containing red pigment found in red blood cells.
It acts as the primary respiratory pigment in human blood.
It is responsible for the transport of $O_2$ from the lungs to the tissues and assists in the transport of $CO_2$ from the tissues back to the lungs.
Therefore,the correct option is $A$.

(D) Serotonin $(5-HT)$ is a neurotransmitter that also acts as a potent vaso-constrictor. When released from platelets during blood vessel injury,it causes the smooth muscles of the blood vessels to contract,thereby reducing blood flow to the site of injury. Therefore,the correct option is $D$.

(B) Blood pressure and osmotic balance in the blood are primarily maintained by plasma proteins.
Albumin is the most abundant plasma protein,accounting for about $54\%$ of the total plasma proteins.
Its primary function is to maintain the colloid osmotic pressure (also known as oncotic pressure) of the blood,which prevents fluid from leaking out of the blood vessels into the surrounding tissues.
Haemoglobin is a respiratory pigment,Fibrinogen is involved in blood clotting,and Heparin is an anticoagulant.
Therefore,the correct answer is Albumin.

(A) The blood consists of a fluid matrix called plasma and formed elements. After the digestion of carbohydrates,proteins,and fats,the resulting nutrients such as glucose,amino acids,fatty acids,and glycerol are absorbed into the blood plasma from the alimentary tract. Therefore,glucose is transported in the blood plasma.

(C) The blood maintains a stable $pH$ (approximately $7.4$) through various buffer systems.
These buffer systems primarily involve bicarbonate ions $(HCO_3^-)$ and carbonic acid $(H_2CO_3)$,as well as plasma proteins and hemoglobin.
The cations associated with these buffer salts in the blood plasma are primarily $Sodium$ $(Na^+)$ and $Potassium$ $(K^+)$,which help maintain the ionic balance and acid-base homeostasis.
Therefore,both sodium and potassium salts play a crucial role in the buffering capacity of the blood.

(C) The average count of $RBC$ (Red Blood Cells) in a healthy adult human is approximately $5,000,000$ ($5$ million) cells per $mm^3$ of blood.
The average count of $WBC$ (White Blood Cells) in a healthy adult human is approximately $6,000$ to $8,000$ cells per $mm^3$ of blood.
Taking the average $WBC$ count as $8,000$ per $mm^3$,the ratio is calculated as $5,000,000 : 8,000 = 625 : 1$.
Rounding this to the nearest standard biological approximation,the ratio is $600 : 1$.

(C) The $pH$ of human blood is slightly alkaline and typically ranges between $7.35$ and $7.45$.
This narrow range is essential for the proper functioning of enzymes and metabolic processes in the body.
Therefore,the correct option is $C$.

(A) The $pH$ of healthy human blood typically ranges from $7.35$ to $7.45$,with an average value of $7.4$.
Since the $pH$ value is greater than $7$,human blood is slightly alkaline in nature.

(B) Haemoglobin is a conjugated protein consisting of a protein part called $Globin$ and a prosthetic group called $Haem$.
$Haem$ is an iron-containing porphyrin ring.
When the iron $(Fe^{2+})$ is removed from the $Haem$ group,the remaining porphyrin structure is known as $Haematin$ (or more specifically,the iron-free derivative is often referred to as $Protoporphyrin$ $IX$).
Among the given options,$Globin$ is the protein component,while $Haematin$ represents the iron-containing or iron-derived pigment structure associated with the breakdown of haemoglobin.

(D) The correct answer is $D$. Rouleaux are columns of $RBCs$ (red blood cells) stacked one above the other like a pile of coins. This phenomenon typically occurs in blood vessels with low flow rates or in conditions where plasma protein concentrations are elevated.

(D) Heparin is a natural anticoagulant produced by the liver and mast cells.
It prevents the clotting of blood inside the blood vessels by inhibiting the formation of thrombin from prothrombin.
Therefore,it keeps the blood in a fluid state within the circulatory system.

(B) The $pH$ of human blood plasma typically ranges from $7.35$ to $7.45$,with an average value of $7.4$.
Since the $pH$ is greater than $7$,the medium is slightly alkaline or basic.

(B) The $pH$ of human blood is strictly maintained between $7.35$ and $7.45$.
This is primarily achieved through the bicarbonate buffer system in the blood.
The equilibrium reaction is represented as: $CO_2 + H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^-$.
The ratio of bicarbonate ions $(HCO_3^-)$ to carbonic acid $(H_2CO_3)$ is critical for buffering excess acids or bases.
Therefore, the balance between sodium bicarbonate $(NaHCO_3)$ and carbonic acid $(H_2CO_3)$ acts as the primary buffer system to maintain blood $pH$.

(D) In a healthy adult human male,the normal concentration of haemoglobin in the blood is typically in the range of $14.0$ to $16.0 \ gms$ per $100 \ ml$ of blood.
Haemoglobin is a red pigment-containing iron found in red blood cells $(RBCs)$ that is responsible for the transport of oxygen throughout the body.
Variations may occur based on age,health status,and altitude,but the standard physiological range for a healthy male is $14-16 \ gms/100 \ ml$.

(B) The process by which leucocytes (white blood cells) squeeze through the pores of the capillary endothelium to reach the site of infection or inflammation is known as diapedesis. This movement is facilitated by the formation of pseudopodia,allowing the cells to exit the blood circulation and enter the surrounding tissues to combat foreign agents.

(C) When a substance like glucose is injected into the bloodstream,it must be isotonic with the blood plasma.
This means the solution must have the same osmotic potential as the blood to prevent the shrinking or bursting of red blood cells (RBCs).
If the solution is hypertonic,cells will shrink; if it is hypotonic,cells will swell and burst.
Therefore,matching the osmotic potential is critical for maintaining cellular homeostasis.

(B) In human blood,the substance responsible for carrying oxygen is $Haemoglobin$.
$Haemoglobin$ is a red-colored iron-containing pigment present in the $RBCs$ (Red Blood Cells).
Each molecule of $Haemoglobin$ can bind with four molecules of $O_2$ to form $Oxyhaemoglobin$,which facilitates the transport of oxygen from the lungs to the tissues.

(C) $RBCs$ (Red Blood Cells) contain the pigment haemoglobin,which binds with oxygen to form oxyhaemoglobin. This process allows the blood to transport oxygen from the lungs to the body tissues.

(C) The correct answer is $C$.
Blood coagulation requires calcium ions $(Ca^{2+})$ as a cofactor for the activation of clotting factors.
Potassium or sodium citrate acts as an anticoagulant by chelating (binding) the calcium ions present in the blood plasma.
By removing free calcium ions,the coagulation cascade is inhibited,thereby preventing the blood from clotting while stored in a blood bank.

(B) In mammalian red blood cells $(RBCs)$,haemoglobin is the primary component of the cytoplasm.
It accounts for approximately $34\%$ of the total weight or biomass of the cell.
This high concentration of haemoglobin is essential for the efficient transport of oxygen throughout the body.

(A) Haemoglobin is a conjugated protein consisting of a protein part called globin and a non-protein prosthetic group called haem.
The globin protein constitutes approximately $95\%$ of the total weight of the haemoglobin molecule.
The remaining $5\%$ is composed of the haem group (iron-containing porphyrin ring),which is responsible for the red colour and oxygen-binding capacity of the blood.
Therefore,the correct composition is $95\%$ globin and $5\%$ haematin (haem).

(B) The spleen is a bean-shaped organ that acts as a filter for the blood.
Old and damaged $RBCs$ are removed from the circulation and destroyed by macrophages through the process of phagocytosis.
Because of this function, the spleen is commonly referred to as the "Graveyard of $RBCs$".

(C) The $Spleen$ is known as the 'graveyard of $RBCs$'.
It acts as a filter for the blood by removing old,damaged,or worn-out red blood cells $(RBCs)$ from the circulation.
Macrophages present in the spleen engulf these aged cells and break them down.

(D) The spleen acts as a reservoir for blood in the human body. It stores red blood cells and platelets,which can be released into the circulation during times of need,such as hemorrhage or physical stress. Therefore,it plays a significant role in regulating blood volume. Thus,the correct option is $D$.

(B) The $ABO$ blood grouping system is based on the presence or absence of two surface antigens,$A$ and $B$,on the surface of red blood cells.
In blood group $A$,the red blood cells possess antigen $A$ on their surface,and the plasma contains antibody $b$ (anti-$B$).
In blood group $B$,the red blood cells possess antigen $B$ on their surface,and the plasma contains antibody $a$ (anti-$A$).
In blood group $AB$,the red blood cells possess both antigens $A$ and $B$,and the plasma contains no antibodies.
In blood group $O$,the red blood cells possess no antigens,and the plasma contains both antibodies $a$ and $b$.
Therefore,antigen $A$ and antibody $b$ are present in blood group $A$.

(B) Antigens are substances that can induce an immune response. In the context of blood groups,antigens (such as $A$ and $B$ antigens) are present on the surface of red blood cells (erythrocytes). These antigens are recognized by the immune system,which produces specific antibodies that react with them.

(B) The biconcave shape of mammalian $RBCs$ (erythrocytes) increases the surface area-to-volume ratio.
This structural adaptation allows for a more rapid diffusion and exchange of respiratory gases,specifically ${O_2}$ and $CO_2$,across the cell membrane.
Therefore,the correct option is $B$.

(C) Blood is a specialized connective tissue.
Connective tissues are derived from the mesoderm during embryonic development.
Therefore,blood is mesodermal in origin.

(B) The clumping of $RBCs$ is known as agglutination.
This occurs when the antibodies present in the serum of one person react with the specific antigens present on the surface of the $RBCs$ of another person.
This is a classic example of an antigen-antibody reaction,which is the basis for blood typing and cross-matching before blood transfusions.
Therefore,the correct option is $B$.

(A) The spleen acts as a filter for the blood. Macrophages present in the spleen engulf and destroy worn-out blood corpuscles,dead and live pathogens,cell debris,pigment granules,and other useless particulate materials. Thus,it regularly cleans the blood of its impurities.

(D) The process by which various types of blood cells are formed is called haemopoiesis or haematopoiesis.
$A$. Haemagglutination is the clumping of red blood cells.
$B$. Haemolysis is the destruction of red blood cells.
$C$. Haemophilia is a genetic disorder that impairs the body's ability to make blood clots.
$D$. Haemopoiesis is the correct term for the production of blood cells.

(C) In vertebrates,the process of yolk formation is known as vitellogenesis.
This process typically occurs in the liver of the female organism.
The synthesized yolk proteins (such as vitellogenin) are then transported through the bloodstream to the developing oocytes (ovum) in the ovary,where they are deposited.

(A) Blood stored in blood banks for transfusion is typically kept at a temperature range of $1^{\circ}C$ to $6^{\circ}C$,with $4^{\circ}C$ being the standard storage temperature. This temperature range is critical to slow down the metabolic activity of red blood cells,minimize the growth of any potential bacteria,and preserve the viability and function of the blood components.

(D) Stored blood is typically preserved using anticoagulants such as sodium citrate,double oxalate (sodium and ammonium),dicumarol,and $EDTA$.
Under standard blood banking conditions,whole blood can be stored for a maximum period of $21$ days before it must be transfused to ensure safety and efficacy.

(B) The correct answer is $B$.
Blood banks use anticoagulants to prevent blood samples from clotting.
Common anticoagulants include Citrate-Phosphate Dextrose $(C.P.D.)$,Acid Citrate Dextrose $(A.C.D.)$,Ethylene Diamine Tetraacetic Acid $(E.D.T.A.)$,and oxalates or citrates.
These substances function by chelating or immobilizing the calcium ions $(Ca^{2+})$ present in the blood,which are essential for the coagulation cascade.

(A) Individuals with blood group $B$ possess $B$ antigens on the surface of their red blood cells and anti-$A$ antibodies in their plasma.
During a blood transfusion,the recipient must not receive antigens that their immune system would recognize as foreign.
Therefore,a patient with blood group $B$ can receive blood from donors with blood group $B$ (same antigen) or blood group $O$ (which lacks both $A$ and $B$ antigens and is considered the universal donor).
Thus,the correct options are $O$ and $B$.

(C) person with blood group $A$ has $A$ antigens on the surface of their red blood cells and anti-$B$ antibodies in their plasma.
Therefore,they can receive blood from individuals who do not have $B$ antigens,which includes blood groups $A$ and $O$.
Blood group $O$ is considered the universal donor because it lacks both $A$ and $B$ antigens,making it compatible with all blood types.

(D) The $Rh$ blood group system is determined by the presence or absence of the $Rh$ antigen (also known as the $D$ antigen) on the surface of red blood cells.
To detect the $Rh$ factor,an antisera containing antibodies against the $D$ antigen,known as Anti-$D$,is used.
If agglutination occurs when Anti-$D$ is added to a blood sample,the individual is $Rh$-positive $(Rh^+)$.
If no agglutination occurs,the individual is $Rh$-negative $(Rh^-)$.