Blood and Blood Group Questions in English

(C) The respiratory pigment responsible for the transport of oxygen in the blood of vertebrates,including frogs,is $Haemoglobin$.
$Haemoglobin$ is an iron-containing metalloprotein found in red blood cells that binds to oxygen to form $Oxyhaemoglobin$,facilitating its transport from the respiratory organs to the tissues.

(D) In adults, red bone marrow $(myeloid \text{ tissue})$ is the primary site for hematopoiesis. It is responsible for the production of red blood cells $(RBCs)$, granular leucocytes, and platelets.

(B) In mammals,bone marrow is the primary site of haematopoiesis,which is the process of blood cell formation. It contains stem cells that differentiate into red blood cells,white blood cells,and platelets. Therefore,it acts as a haemopoietic tissue.

(B) The correct answer is $B$.
Polycythemia is a condition characterized by an abnormal increase in the number of red blood cells $(R.B.C.)$ in the blood.
Anaemia refers to a decrease in the number of $R.B.C.$ or hemoglobin.
Leukemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase in white blood cells $(W.B.C.)$.

(C) The average life span of human $RBCs$ (erythrocytes) is approximately $120$ days.
After this period,they are destroyed in the spleen,which is often referred to as the 'graveyard of $RBCs$'.
In contrast,the life span of $RBCs$ in a frog is $100$ days,and in a rabbit,it is $80$ days.

(A) The term $Leukopenia$ is used when the count of white blood cells $(W.B.C.)$ decreases below the normal range,typically below $5,000$ cells per cubic millimeter of blood.
$Leukemia$ refers to a cancer of blood-forming tissues,often characterized by an abnormally high count of immature $W.B.C.s$.
$Anaemia$ refers to a deficiency in the number of red blood cells or hemoglobin in the blood.
Therefore,the correct answer is $Leukopenia$.

(A) Monocytes are the largest leucocytes,typically ranging from $12-15 \ \mu m$ in size.
They constitute approximately $2-8\%$ of the total $W.B.C.$ count.
Among the given options,$5.3\%$ falls within the standard physiological range for monocytes.

(A) In adults,the process of formation of blood cells,known as hematopoiesis,occurs primarily in the red bone marrow.
Specifically,the red bone marrow found in the epiphyses of long bones,as well as in the ribs,sternum,vertebrae,and pelvis,is responsible for the production of red blood corpuscles $(R.B.C.)$,white blood corpuscles $(W.B.C.)$,and platelets.
Therefore,the correct option is $A$.

(B) Most mammals have circular,biconcave,and non-nucleated $RBCs$ (erythrocytes) to maximize surface area for oxygen transport.
However,camels (members of the family $Camelidae$) are an exception.
Their erythrocytes are oval in shape and contain a nucleus,which is a unique adaptation for these animals.

(B) White blood cells $(WBCs)$,also known as leukocytes,are characterized by having a nucleus that is irregular in shape.
Specifically,granulocytes (neutrophils,eosinophils,and basophils) possess lobed nuclei,which are considered irregular.
Even in agranulocytes,the nuclei are often kidney-shaped or indented,rather than perfectly spherical or oval.
Therefore,the most accurate general description for the nucleus of $WBCs$ is irregular.

(A) The $pH$ of human blood is slightly alkaline,typically ranging between $7.35$ and $7.45$.
Among the given options,$7.4$ is the standard value representing the physiological $pH$ of human blood.

(A) Sodium oxalate,sodium citrate,and $EDTA$ (Ethylene diamine tetra acetic acid) are used as anticoagulants in laboratories and blood banks.
These substances function by binding to $Ca^{++}$ ions,which are essential for the blood coagulation cascade.
By removing free $Ca^{++}$ ions from the blood,they prevent the conversion of prothrombin to thrombin,thereby inhibiting clotting.
These compounds are known as chelating agents.

(B) Distilled water is a hypotonic solution compared to the cytoplasm of red blood cells $(RBCs)$.
When $RBCs$ are placed in distilled water,water enters the cells through the process of endosmosis.
As water enters,the volume of the $RBCs$ increases.
Since animal cells lack a cell wall to provide structural support,the membrane eventually ruptures,causing the cells to burst.

(B) The red pigment in vertebrate blood is $Hemoglobin$.
$Hemoglobin$ is a conjugated protein consisting of a protein part called $Globin$ and a prosthetic group called $Heme$.
$Heme$ is an iron-porphyrin complex, which means it contains an $Iron$ $(Fe^{2+})$ ion at its center.
This $Iron$ ion is responsible for the binding of $Oxygen$ and gives blood its characteristic red color.

(B) Blood is a fluid connective tissue,which consists of blood corpuscles ($RBCs$,$WBCs$,and platelets) and plasma. Therefore,the correct composition includes plasma,red blood cells,white blood cells,and platelets.

(B) The rate of $RBC$ (Red Blood Cell) formation,also known as erythropoiesis,is regulated by the oxygen demand of the body.
During sleep,the metabolic rate of the body decreases,leading to a lower consumption of oxygen compared to the active state.
Since the oxygen requirement is reduced,the stimulus for erythropoietin production (the hormone that stimulates $RBC$ production) decreases.
Therefore,the rate of $RBC$ formation decreases during sleep.

(B) The rate of erythropoiesis (the process of red blood cell formation) is primarily regulated by a hormone called erythropoietin.
This hormone is synthesized and released into the bloodstream mainly by the kidneys in response to low oxygen levels in the blood (hypoxia).
Therefore,the correct option is $(b)$.

(C) Blood is a special type of connective tissue that consists of a fluid matrix,plasma,and formed elements. The formed elements include erythrocytes $(RBCs)$,leucocytes $(WBCs)$,and platelets. Therefore,vascular tissue or fluid tissue is composed of all these components.

(A) Leucocytes are considered as true cells because they possess a nucleus and other cell organelles like mitochondria,Golgi apparatus,and centrioles,which are characteristic of a complete cell.
In contrast,mature mammalian erythrocytes (RBCs) lack a nucleus and most organelles,which is why they are not considered 'true' cells in the strict biological sense.

(B) Reticulocytes are the precursor cells of mature $RBCs$ (erythrocytes).
During the process of erythropoiesis in the bone marrow,the cell loses its nucleus and other organelles to become a reticulocyte.
These cells are released into the bloodstream,where they mature into fully functional $RBCs$ within $1-2$ days.
Therefore,reticulocytes are essentially immature erythrocytes.

(C) The correct answer is $C$.
$RBC$ (Red Blood Cells) contain a respiratory pigment called haemoglobin.
Haemoglobin is a conjugated protein that contains iron as its prosthetic group (haem).
Therefore,the highest concentration of iron in the blood is found within the $RBC$s.

(B) The lifespan of $RBC$ (Red blood corpuscles) in humans is approximately $120$ days.
In contrast,white blood cells $(WBC)$ have much shorter lifespans,typically ranging from a few hours to a few days.
Therefore,$RBC$ have the longest lifespan among the given options.

(A) Neutrophils are the most abundant white blood cells,comprising approximately $60-65\%$ of the total white blood cell count in human blood.
Eosinophils account for $2-3\%$,Basophils account for $0.5-1\%$,and Lymphocytes account for $20-25\%$ of the total white blood cells.
Therefore,Neutrophils occur in the greatest proportion.

(C) Monocytes are the largest white blood cells (leukocytes) in mammalian blood. They are agranulocytes and are phagocytic in nature,meaning they engulf and digest cellular debris and pathogens.

(A) The liver produces an anticoagulant,a hetero-polysaccharide known as heparin.
This substance prevents the coagulation of blood within the blood vessels by inhibiting the action of thrombin and other clotting factors.

(A) Agranulocytes are leukocytes that lack granules in the cytoplasm.
Lymphocytes and monocytes are the two main types of agranulocytes.
Since lymphocytes do not have granules in their cytoplasm,they are classified as agranulocytes.
In contrast,eosinophils,basophils,and neutrophils are granulocytes because they contain granules in their cytoplasm.

(A) The life span of human $WBC$s (leukocytes) varies significantly depending on the type of cell.
Granulocytes (neutrophils,eosinophils,and basophils) typically have a short life span,circulating in the blood for $4-8$ hours and residing in tissues for $4-5$ days.
Monocytes have a life span of $10-20$ hours in the blood before migrating into tissues to become macrophages.
Lymphocytes can live for days,months,or even years depending on the immunological memory requirements.
However,in the context of standard multiple-choice questions regarding the average short-lived $WBC$s,the most appropriate answer is less than $10$ days.

(B) White blood cells are categorized into two main types based on the presence or absence of granules in their cytoplasm:
$1$. Granulocytes: These contain granules in their cytoplasm and include Neutrophils,Eosinophils (Acidophils),and Basophils.
$2$. Agranulocytes: These lack granules in their cytoplasm and include Lymphocytes and Monocytes.
Therefore,Monocytes are agranulocytes,not granulocytes.

(B) In the embryonic stage,$RBCs$ (red blood cells) are produced in the liver and spleen. This process is known as erythropoiesis. In adults,the primary site for $RBC$ production is the bone marrow. The liver also plays a role in adults by storing inorganic salts of iron,copper,and vitamin $B_{12}$,which are essential for the formation of red blood cells and hemoglobin.

(C) The chief difference between $RBCs$ of humans and frogs is that human $RBCs$ are enucleated (without a nucleus) at maturity,whereas frog $RBCs$ are nucleated.
The absence of a nucleus in mammalian $RBCs$ allows for more space to accommodate haemoglobin,which increases the oxygen-carrying capacity and respiratory efficiency of the cells.

(A) Basophils are a type of white blood cell that play a key role in inflammatory responses.
Their cytoplasmic granules contain chemical mediators such as heparin (an anticoagulant),histamine (a vasodilator),and serotonin.

(A) Vitamin $K$,also known as the anti-haemorrhagic factor,is a fat-soluble vitamin.
It is essential for the synthesis of prothrombin (clotting factor $II$) in the liver.
Prothrombin is a precursor protein that is later converted into thrombin during the blood coagulation cascade.

(A) Phagocytes are cells that protect the body by ingesting harmful foreign particles,bacteria,and dead or dying cells.
Among the given options,$WBCs$ (White Blood Cells),specifically neutrophils and monocytes,act as phagocytes.
$RBCs$ are involved in oxygen transport,while enzymes and hormones are biochemical substances,not cells.

(C) Serum is the clear,yellowish,watery fluid that remains after blood has clotted.
During the process of blood coagulation,the protein fibrinogen is converted into fibrin threads,which form the clot.
Therefore,serum is essentially blood plasma from which the clotting factors (specifically fibrinogen) and blood cells (corpuscles) have been removed.

(C) Blood is a connective tissue that contains plasma,$RBCs$ (erythrocytes),$WBCs$ (leukocytes),and platelets.
Lymph is a fluid connective tissue that is essentially filtered blood plasma.
Lymph lacks $RBCs$ and platelets but contains lymphocytes $(WBCs)$ which are responsible for immune responses.
Therefore,blood contains both $RBCs$ and $WBCs$,while lymph contains only $WBCs$ (specifically lymphocytes) and lacks $RBCs$.

(B) Blood coagulation is a complex process involving various clotting factors.
$1$. Vitamin $K$ is essential for the synthesis of clotting factors like $II$,$VII$,$IX$,and $X$ in the liver.
$2$. Calcium ions $(Ca^{2+})$ play a critical role in the activation of several clotting factors and the conversion of prothrombin to thrombin.
$3$. Fibrinogen is a soluble plasma protein that is converted into insoluble fibrin threads to form a blood clot.
$4$. Vitamin $D$ is primarily involved in calcium homeostasis and bone health,and it does not have a direct role in the blood coagulation cascade.

(D) . Monocytes are the largest leucocytes,with a size of $12-20 \ \mu m$. Their lifespan is variable,ranging from a few to several days. They possess a bean-shaped nucleus and exhibit a phagocytic nature,helping to engulf pathogens and cellular debris.

(B) Hematology is the branch of medicine and biology concerned with the study of blood,blood-forming organs,and blood diseases. The term is derived from the Greek word 'haima' meaning blood and 'logos' meaning study.

(B) $G-6-P$ dehydrogenase (Glucose$-6-$phosphate dehydrogenase) is an enzyme that plays a crucial role in the pentose phosphate pathway within cells.
In $RBCs$ (Red Blood Cells),this enzyme is essential for producing $NADPH$,which helps maintain the levels of reduced glutathione.
Reduced glutathione protects $RBCs$ from oxidative damage caused by reactive oxygen species.
When $G-6-P$ dehydrogenase is deficient,$RBCs$ become susceptible to oxidative stress,leading to their premature destruction,a process known as haemolysis.

(B) The correct answer is $(b)$. The spleen is a secondary lymphoid organ that acts as a filter for the blood. It is responsible for removing old, damaged, or malformed red blood cells $(RBCs)$ from circulation. Due to this function of destroying worn-out $RBCs$, the spleen is commonly referred to as the "Graveyard of $RBCs$".

(A) The process of formation of blood corpuscles (red blood cells,white blood cells,and platelets) is known as $Haemopoiesis$ (or $Hematopoiesis$).
$Haemolysis$ refers to the destruction of red blood cells.
$Haemozoin$ is a toxic byproduct produced by the malaria parasite $Plasmodium$ during its life cycle in human red blood cells.
Therefore,the correct option is $A$.

(D) $Monocytes$,$Lymphocytes$,and $Neutrophils$ are types of $Leukocytes$ (White Blood Cells),which are involved in the immune response of the body.
$Erythrocytes$ (Red Blood Cells) are responsible for the transport of respiratory gases like $O_2$ and $CO_2$.
Therefore,$Erythrocytes$ is the odd one out as it is not a type of white blood cell.

(D) Vitamin $K$ is essential for the process of blood clotting (coagulation). It acts as a cofactor for the synthesis of clotting factors in the liver,such as factors $II$,$VII$,$IX$,and $X$. Without sufficient Vitamin $K$,the body cannot produce these proteins effectively,leading to prolonged bleeding.

(A) Blood clotting (coagulation) is a complex process involving a cascade of clotting factors. Factor $XII$ (Hageman factor) is a serine protease that plays a critical role in the intrinsic pathway of blood coagulation. When it comes into contact with negatively charged surfaces (like collagen exposed in damaged blood vessels),it undergoes a conformational change (modification) and becomes activated,initiating the clotting cascade that leads to spontaneous blood clotting.

(B) Both $Folic \, acid$ (Vitamin $B_9$) and $Cobalamine$ (Vitamin $B_{12}$) are crucial for the synthesis of $DNA$ and the maturation of erythrocytes (red blood cells). Deficiency in either leads to megaloblastic anemia. However, in many standard biological contexts, $Cobalamine$ is specifically highlighted as the maturation factor for erythrocytes. Given the options, both $A$ and $B$ are biologically correct, but $Cobalamine$ is the classic answer for the 'erythrocyte maturation factor'.

(C) The blood clotting factor $IV$ is calcium ions $(Ca^{2+})$.
Calcium ions are essential for the coagulation process but are not synthesized by the liver.
Factors $I$ (fibrinogen),$II$ (prothrombin),and $VIII$ (antihemophilic factor) are proteins synthesized by the liver.

(C) Vitamin $K$ is essential for the synthesis of several clotting factors in the liver,including prothrombin (factor $II$),factor $VII$,factor $IX$,and factor $X$.
These factors are crucial for the blood coagulation cascade.
Therefore,vitamin $K$ plays a vital role in the normal clotting process of blood.

(A) Vitamin $K$ is essential for the synthesis of prothrombin in the liver,which is required for the normal clotting of blood.
Therefore,a deficiency of vitamin $K$ leads to a failure of blood clotting,which can result in hemorrhage and excessive bleeding from wounds.

(D) The liver acts as a storage organ for vitamin $B_{12}$ (cobalamin) in the body. Vitamin $B_{12}$ is essential for the maturation of $RBCs$ (erythropoiesis). $A$ deficiency of vitamin $B_{12}$ leads to pernicious anaemia. Therefore,liver extracts or tonics are rich in vitamin $B_{12}$ and are effective in treating anaemias caused by its deficiency.

(C) Vitamin $B_{12}$ (cyanocobalamin) is essential for the maturation of red blood cells.
It acts on the bone marrow to stimulate the production of $RBCs$ and platelets.
It promotes haemopoiesis (the formation of blood cellular components).