Blood and Blood Group Questions in English

(A) Blood plasma is a straw-colored,viscous fluid constituting the matrix of the blood.
It consists of $90-92\, \%$ water and proteins contribute $6-8\, \%$ of the plasma.
The major proteins present in plasma are fibrinogen,globulins,and albumins.
Therefore,the correct composition is $90-92\, \%$ water and $6-8\, \%$ proteins.

(C) The plasma proteins are essential for various physiological functions:
$1$. $P$. Fibrinogen: These are blood clotting factors that are converted into fibrin during the process of blood coagulation. Thus, $P-I$.
$2$. $Q$. Globulins: These are primarily involved in the defense mechanisms of the body (e.g., antibodies are immunoglobulins). Thus, $Q-III$.
$3$. $R$. Albumins: These are plasma proteins that help in maintaining the osmotic balance of the blood. Thus, $R-II$.
Therefore, the correct matching is $(P-I), (Q-III), (R-II)$.

(D) Blood plasma is the straw-colored, viscous fluid constituting the matrix of the blood.
When blood is allowed to clot, the fluid that remains is called serum.
During the process of blood coagulation, clotting factors (like fibrinogen) are consumed or removed from the plasma.
Therefore, serum is defined as plasma from which the clotting factors have been removed.
Thus, $Serum = \text{Plasma} - \text{Clotting factors}$.

(A) The average count of blood cells per $mm^3$ of blood is as follows:
$1$. Erythrocytes (RBCs): Healthy adult men have on average $5$ to $5.5$ million RBCs per $mm^3$ of blood $(P-III)$.
$2$. Leukocytes (WBCs): The average count of WBCs is $6,000$ to $8,000$ per $mm^3$ of blood $(Q-II)$.
$3$. Thrombocytes (Platelets): The number of platelets in the blood ranges from $1.5$ to $3.5$ lakh per $mm^3$ of blood $(R-I)$.
Therefore,the correct matching is $(P-III), (Q-II), (R-I)$.

(A) In a healthy human adult,the average concentration of hemoglobin is approximately $12 - 16 \text{ grams}$ per $100 \text{ mL}$ of blood.
This protein is essential for the transport of oxygen throughout the body.
Therefore,the correct option is $A$.

(C) Erythrocytes (Red Blood Cells) are the most abundant cells in the blood. In humans,they are produced in the red bone marrow. They possess a biconcave shape to increase surface area for gas exchange. However,the statement that 'erythrocytes are enucleated in all mammals' is incorrect. While most mammals have enucleated RBCs,members of the family Camelidae (such as camels and llamas) possess nucleated erythrocytes.

(C) The $Spleen$ is a bean-shaped organ located in the upper-left part of the abdomen.
It acts as a filter for the blood and is responsible for removing old, damaged, or worn-out red blood cells $(RBCs)$ from the circulation.
Because it destroys these aged cells, it is commonly referred to as the 'graveyard of red blood cells'.

(B) White blood cells $(WBCs)$ are classified into two main categories based on the presence or absence of granules in their cytoplasm:
$1$. Granulocytes: These contain granules in their cytoplasm. They include Neutrophils,Eosinophils,and Basophils.
$2$. Agranulocytes: These lack granules in their cytoplasm. They include Lymphocytes and Monocytes.
Therefore,the correct classification is: Granulocytes $(Eosinophils, Basophils, Neutrophils)$ and Agranulocytes $(Lymphocytes, Monocytes)$.

(C) The percentage of different types of white blood cells (WBCs) in human blood is as follows:
$1$. Neutrophils: $60-65\%$ $(P-IV)$
$2$. Eosinophils: $2-3\%$ $(Q-III)$
$3$. Basophils: $0.5-1.0\%$ $(R-I)$
$4$. Monocytes: $6-8\%$ $(S-II)$
$5$. Lymphocytes: $20-25\%$ $(T-V)$
Therefore,the correct matching is $(P-IV), (Q-III), (R-I), (S-II), (T-V)$.

(D) The white blood cell shown in the image has a large,kidney-shaped or bean-shaped nucleus,which is characteristic of a monocyte.
Monocytes are agranulocytes and constitute approximately $6-8\%$ of the total white blood cells (WBCs) in the blood.
Therefore,the correct percentage is $6-8\%$.

(D) Based on the provided image:
$P$ represents an Eosinophil,which is involved in allergic reactions and parasitic infections.
$Q$ represents a Neutrophil,which is a polymorphonuclear leukocyte and acts as a primary phagocytic cell.
$R$ represents a Monocyte,which differentiates into macrophages and acts as a major phagocytic cell.
Both Neutrophils $(Q)$ and Monocytes $(R)$ are phagocytic in nature.
Therefore,the correct option is $Q$ and $R$.

(A) The image shows biconcave,disc-shaped cells without a nucleus. These are characteristic features of erythrocytes (Red Blood Cells or RBCs).
Erythrocytes are responsible for the transport of respiratory gases like $O_2$ and $CO_2$ in the blood.

(D) Phagocytosis is a process by which cells engulf and digest cellular debris,foreign substances,or pathogens.
Among the given white blood cells (leukocytes):
$1$. Neutrophils $(I)$ are the most abundant leukocytes and are highly active phagocytic cells that destroy foreign organisms entering the body.
$2$. Monocytes $(II)$ are large leukocytes that differentiate into macrophages in tissues,which are professional phagocytes.
$3$. Lymphocytes $(III)$ are primarily involved in immune responses ($B$-cells and $T$-cells) and are not phagocytic.
$4$. Eosinophils $(IV)$ are mainly involved in allergic reactions and parasitic infections.
$5$. Basophils $(V)$ are involved in inflammatory reactions and release histamine,serotonin,and heparin.
Therefore,Neutrophils and Monocytes are the primary phagocytic cells.

(C) Basophils are a type of granulocyte white blood cell.
They contain granules that store various chemical mediators.
These cells are responsible for secreting substances such as histamine (a vasodilator),serotonin (a neurotransmitter),and heparin (an anticoagulant).
Therefore,the correct option is $C$.

(C) Basophils are a type of white blood cell that play a crucial role in inflammatory reactions.
They secrete chemicals such as histamine,serotonin,and heparin.
Histamine is a vasodilator that increases blood flow to the site of injury or infection,which is a key component of the inflammatory response.
Neutrophils and monocytes are primarily involved in phagocytosis (engulfing pathogens).
Eosinophils are primarily associated with allergic reactions and parasitic infections.

(B) The image shows a basophil,which is a type of white blood cell (leukocyte).
Basophils are characterized by their coarse,dark-staining granules in the cytoplasm and a lobed nucleus.
They secrete chemicals like histamine,serotonin,and heparin.
These chemicals are involved in inflammatory reactions and are also associated with allergic reactions.

(B) Thrombocytes,or blood platelets,are cell fragments produced from special cells in the bone marrow called megakaryocytes ($I, II, III$ are correct).
They are essential for the process of blood coagulation or clotting ($V$ is correct).
The normal count of platelets in a healthy human individual is $1,50,000$ to $3,50,000$ per $mm^3$. Therefore,statement $IV$ is incorrect because the range provided in the option is higher than the standard physiological range.
Thus,the correct statements are $I, II, III,$ and $V$.

(B) The universal donor is the blood group that can be given to individuals of any blood type without causing an immune reaction.
$O^{-}$ blood type lacks both $A$ and $B$ antigens on the surface of red blood cells and also lacks the $Rh$ factor.
Because it does not have these antigens,it does not trigger an immune response in the recipient's body,making $O^{-}$ the universal donor.

(C) The $AB^{+}$ blood group is considered the universal recipient.
This is because individuals with $AB^{+}$ blood have both $A$ and $B$ antigens on the surface of their red blood cells and possess the $Rh$ factor.
Consequently,their immune system does not produce antibodies against $A$,$B$,or $Rh$ antigens,allowing them to receive blood from any $ABO$ or $Rh$ blood group type without an adverse immune reaction.

(A) person with $A^+$ blood group has $A$ antigens and $Rh$ antigens on their red blood cells.
They can donate blood to individuals who have both $A$ and $Rh$ antigens,which means they can donate to $A^+$ and $AB^+$ blood groups.
$A^+$ individuals can receive blood from $A^+, A^-, O^+, O^-$,but they can only donate to those who possess the $Rh$ factor and the $A$ antigen.

(D) In the $ABO$ blood grouping system,the presence or absence of antigens on the surface of red blood cells determines the blood group.
Blood group $O$ individuals possess neither $A$ nor $B$ antigens on their red blood cells.
However,their plasma contains both anti-$A$ and anti-$B$ antibodies.
Therefore,individuals with blood group $O$ are considered universal donors because their red blood cells lack antigens that could trigger an immune response in recipients.

(C) In the $ABO$ blood grouping system, the presence or absence of surface antigens on red blood cells determines the blood type.
$1$. Blood group $A$ has antigen $A$ on RBCs and antibody $b$ (anti-$A$) in plasma.
$2$. Blood group $B$ has antigen $B$ on RBCs and antibody $a$ (anti-$B$) in plasma.
$3$. Blood group $AB$ has both antigens $A$ and $B$ on RBCs and no antibodies in plasma.
$4$. Blood group $O$ has no antigens on RBCs and both antibodies $a$ and $b$ in plasma.
Therefore, the correct matching is:
$P$ (Blood group $A$) matches with $III$ (antibody $b$).
$Q$ (Blood group $B$) matches with $II$ (antibody $a$).
$R$ (Blood group $AB$) matches with $I$ (absent).
$S$ (Blood group $O$) matches with $IV$ (antibodies $a, b$).
Thus, the correct sequence is $P-III, Q-II, R-I, S-IV$.

(B) The compatibility of blood groups for donation is based on the presence of antigens on the surface of red blood cells and antibodies in the plasma.
$1$. Blood group $A$ has antigen $A$ and can donate to $A$ and $AB$ $(P-IV)$.
$2$. Blood group $B$ has antigen $B$ and can donate to $B$ and $AB$ $(Q-II)$.
$3$. Blood group $AB$ has both antigens $A$ and $B$ and can donate only to $AB$ $(R-I)$.
$4$. Blood group $O$ has no antigens and is the universal donor, meaning it can donate to $A, B, AB,$ and $O$ $(S-III)$.
Therefore, the correct matching is $P-IV, Q-II, R-I, S-III$.

(C) The $ABO$ blood grouping system is based on the presence or absence of two surface antigens,$A$ and $B$,on the red blood cells.
Individuals with blood group $A$ have antigen $A$ on their red blood cells.
Individuals with blood group $B$ have antigen $B$ on their red blood cells.
Individuals with blood group $AB$ possess both antigen $A$ and antigen $B$ on their red blood cells.
Individuals with blood group $O$ do not have either antigen $A$ or antigen $B$ on their red blood cells.
Therefore,the correct answer is blood group $AB$.

(D) Erythroblastosis fetalis is a hemolytic disease of the newborn caused by an $Rh$ incompatibility between the mother and the fetus.
This condition occurs when the mother is $Rh$-negative $(Rh^{-ve})$ and the father is $Rh$-positive $(Rh^{+ve})$.
If the fetus inherits the $Rh$ antigen from the father,the fetus becomes $Rh$-positive.
During the first delivery,the mother's blood is exposed to the $Rh$ antigen of the fetus,leading to the formation of anti-$Rh$ antibodies in the mother's blood.
In subsequent pregnancies,if the fetus is again $Rh$-positive,these maternal anti-$Rh$ antibodies can cross the placenta and destroy the fetal red blood cells,leading to severe anemia and jaundice.

(A) The $Rh$ antigen is a protein found on the surface of red blood cells.
It is named after the Rhesus monkey,in which it was first discovered.
In the human population,approximately $80 \%$ of individuals are $Rh$-positive $(Rh^+)$,meaning they possess the $Rh$ antigen on their red blood cells.
The remaining $20 \%$ are $Rh$-negative $(Rh^-)$,meaning they lack this antigen.
Therefore,the correct percentage of the population that possesses the $Rh$ antigen is $80 \%$.

(B) The $Rh$ factor is an inherited protein found on the surface of red blood cells. It was first discovered by Karl Landsteiner and Alexander $S$. Wiener in $1940$. They identified this antigen on the surface of red blood cells of the Rhesus monkey (Macaca mulatta). Hence,it is named '$Rh$' factor after the Rhesus monkey.

(D) The process of blood clotting involves a cascade of enzymatic reactions.
Prothrombin is an inactive plasma protein that is converted into its active form,thrombin,by the enzyme complex known as prothrombinase or thrombokinase (Factor $X_a$).
This reaction is strictly dependent on the presence of calcium ions $(Ca^{2+})$ and phospholipids.
While thrombokinase acts as the enzyme,calcium ions are essential cofactors for the activation of prothrombin.
In the context of standard biological questions regarding the conversion of prothrombin,calcium is often cited as the critical requirement for the activation process.

(C) During the process of blood coagulation,an enzyme complex called thrombokinase helps in the formation of the enzyme thrombin from inactive prothrombin present in the plasma.
Thrombin then acts as a catalyst to convert the soluble protein fibrinogen into insoluble fibrin threads.
Therefore,thrombin is the specific enzyme required for the conversion of fibrinogen into fibrin.

(A) The process of blood coagulation involves a cascade of enzymatic reactions.
$1$. Injury to a blood vessel triggers the release of factors that form an enzyme complex called $Thrombokinase$ (or $Prothrombin$ activator).
$2$. $Thrombokinase$ converts inactive $Prothrombin$ in the plasma into active $Thrombin$.
$3$. $Thrombin$ then converts inactive $Fibrinogen$ into insoluble $Fibrin$ threads.
$4$. These $Fibrin$ threads form a meshwork that traps blood cells to form a clot.
Therefore,$Fibrin$ is the final product formed in the coagulation cascade.

(D) The blood group $O$ is represented by the genotype $ii$,meaning the daughter must have inherited one $i$ allele from each parent.
Since the father has blood group $B$,his possible genotypes are $I^B I^B$ (homozygous) or $I^B i$ (heterozygous).
For the daughter to have the $ii$ genotype,the father must contribute an $i$ allele.
Therefore,the father must be heterozygous for blood group $B$,which is represented by the genotype $I^B i$.

(A) The child has blood group $O$,which means the genotype is $ii$.
One $i$ allele is inherited from the mother and the other $i$ allele is inherited from the father.
The mother has blood group $A$,so her genotype must be $I^A i$ to provide an $i$ allele to the child.
The father must provide the other $i$ allele.
Therefore,the father's genotype must contain at least one $i$ allele ($I^A i$,$I^B i$,or $ii$).
$A$ person with blood group $AB$ has the genotype $I^A I^B$.
Since an $AB$ individual does not possess the $i$ allele,they cannot be the father of a child with blood group $O$.

(B) The alleles for the $ABO$ blood group system code for specific sugar polymers (antigens) that are present on the surface of the plasma membrane of red blood cells $(RBCs)$.
These antigens are determined by the gene $I$,which has three alleles: $I^A$,$I^B$,and $i$.
Therefore,the expression of these alleles in the form of antigens occurs on the surface of red blood cells.

(A) $PMNL$ stands for Polymorphonuclear Leucocytes.
These are a type of white blood cell characterized by having a multi-lobed nucleus.
They are also known as neutrophils and are a key component of the innate immune system,acting as phagocytes to engulf pathogens.

(D) Phagocytosis is the process by which cells engulf and digest cellular debris,foreign substances,or pathogens.
Among the given options,$Neutrophils$ and $Monocytes$ are the primary phagocytic cells in the blood.
$Neutrophils$ are the most abundant type of white blood cells and act as the first line of defense by performing phagocytosis to destroy invading bacteria.
$Eosinophils$ are primarily involved in allergic reactions and parasitic infections.
$Basophils$ release histamine and heparin during inflammatory responses.
$Lymphocytes$ are responsible for the specific immune response ($T$-cells and $B$-cells).
Therefore,the correct option is $D$.

(B) Non-nucleated blood cells,specifically mature mammalian red blood cells ($RBCs$ or erythrocytes),are produced in the bone marrow. During erythropoiesis in the bone marrow,the developing red blood cells lose their nucleus to provide more space for hemoglobin,which increases the oxygen-carrying capacity of the blood.

(A) The abundance of formed elements in human blood is as follows:
$1$. Erythrocytes $(RBCs)$: $5.0-5.5$ million/$mm^3$ (Most abundant).
$2$. Platelets: $150,000-350,000$ per $mm^3$.
$3$. Neutrophils: $60-65\%$ of total $WBCs$.
$4$. Monocytes: $6-8\%$ of total $WBCs$.
$5$. Eosinophils: $2-3\%$ of total $WBCs$.
Comparing the absolute numbers, the order of abundance is: Erythrocytes > Platelets > Neutrophils > Monocytes > Eosinophils.
Thus, the correct sequence is $(c), (a), (b), (e), (d)$.

Option (4) is the answer because, basophils secrete histamine, serotonin, heparin etc. and are involved in inflammatory response.

Option (3) is not the answer because, basophils are granulocytes.

Option (1) is not the answer because, neutrophils are the most abundant cells $(60-65 \%)$ of the total WBCs whereas basophils are least $(0.5-1 \%)$ abundant of all WBCs.

Option (2) is not the answer because, monocytes have a kidney-shaped nucleus.

(D) Leucocytes (White Blood Cells) are categorized into granulocytes and agranulocytes.
Among the different types of leucocytes,neutrophils are the most abundant cells,constituting approximately $60-65\%$ of the total $\text{WBC}$ count.
Monocytes constitute about $6-8\%$,basophils $0.5-1\%$,and acidophils (eosinophils) $2-3\%$.
Therefore,the correct option is $D$.

(C) White blood cells $(\text{WBCs})$ or leukocytes are classified into granulocytes and agranulocytes.
Among the granulocytes,$\text{neutrophils}$ are the most abundant cells (about $60-65\%$ of total $\text{WBCs}$) and are phagocytic in nature,meaning they engulf and destroy foreign organisms.
Among the agranulocytes,$\text{monocytes}$ (about $6-8\%$) are also phagocytic cells that destroy foreign substances.
Therefore,$\text{neutrophils}$ and $\text{monocytes}$ are the primary phagocytic cells of the blood.

$(C)$ Let us analyze each statement:
$(A)$ Blood is a special connective tissue, not an epithelial tissue. Thus, this statement is incorrect.
$(B)$ Albumins are primarily involved in osmotic balance, whereas clotting factors like fibrinogen are needed for clotting. Thus, this statement is incorrect.
$(C)$ Plasma without the clotting factors is called serum. The statement says 'with', which is incorrect.
$(D)$ Plasma is a straw-coloured, viscous fluid constituting $55\%$ of the blood. This statement is correct.
Therefore, statements $(A)$, $(B)$, and $(C)$ are incorrect. The total number of incorrect statements is $3$.

(C) In the $ABO$ blood grouping system,the presence of antigens on the surface of $RBC$s is determined by the alleles $I^A$,$I^B$,and $i$.
For blood group $AB$,both $A$ and $B$ antigens are present on the $RBC$ surface.
In the $Rh$ blood grouping system,the presence of the $Rh$ factor (also known as the $D$ antigen) determines the positive $(+)$ or negative $(-)$ status.
Since the blood group is $AB$ positive $(AB+)$,it possesses $A$ antigen,$B$ antigen,and $Rh$ $(D)$ antigen.
Therefore,a total of $3$ antigens are present on the surface of the $RBC$.

(C) The $ABO$ blood grouping system is based on the presence or absence of two surface antigens,namely antigen $A$ and antigen $B$,on the surface of red blood cells $(RBCs)$.
Therefore,the correct grouping is $ABO$ and the number of surface antigens involved is two.

(A) When $\text{Rh}$-positive blood is transfused into an $\text{Rh}$-negative individual,the recipient's immune system recognizes the $\text{Rh}$ antigen as foreign.
This triggers the production of anti-$\text{Rh}$ antibodies by the recipient.
These antibodies attack and destroy the transfused $\text{Rh}$-positive red blood cells,a process known as haemolysis (or destruction of red blood cells).
Therefore,the correct consequence of this incompatibility is haemolysis.

(A) Statement-$I$ is correct because in the $ABO$ blood grouping system,$A$ and $B$ antigens are present on the surface of $\text{RBCs}$. An individual can have $A$ antigen,$B$ antigen,both $A$ and $B$ antigens,or neither.
Statement-$II$ is correct because antigens are defined as substances (often proteins or polysaccharides) that,when introduced into the body,are recognized by the immune system as foreign and trigger an immune response,such as the production of antibodies.

(A) Blood group $A$ is determined by the presence of the $A$ antigen on the surface of red blood cells $(RBCs)$.
In individuals with blood group $A$,the plasma (or serum) contains anti-$B$ antibodies,not anti-$A$ antibodies.

(B) The $Rh$ factor,also known as the $Rh$ antigen or antigen '$D$',is a protein found on the surface of red blood cells.
It was first discovered by Karl Landsteiner and Alexander $S$. Weiner in $1940$ while they were studying the blood of Rhesus monkeys.
This discovery is crucial for blood transfusion compatibility and for understanding $Rh$ incompatibility during pregnancy.

(D) $i$. Correct: $ABO$, $Rh$, $Duffy$, $Lewis$, and $Bombay$ are recognized blood group systems.
$ii$. Correct: $A$ and $B$ are $ABO$ antigens, and $D$ is the primary $Rh$ antigen found on $RBC$ surfaces.
$iii$. Incorrect: Individuals with $AB$ $Rh$ $+ve$ blood have $A, B,$ and $D$ antigens, but they lack anti-$A$ and anti-$B$ antibodies in their plasma.
$iv$. Incorrect: Erythroblastosis foetalis occurs when an $Rh$-negative mother carries an $Rh$-positive foetus.
$v$. Incorrect: $AB$ blood group individuals are universal recipients, and $O$ blood group individuals are universal donors.

(B) In addition to the well-known $ABO$ and $Rh$ blood group systems,there are several other blood group systems identified in humans. $Duffy$,$Kidd$,and $Lewis$ are specific examples of these additional blood group systems,which are determined by the presence of specific antigens on the surface of red blood cells. Therefore,the correct option is $B$.

(C) The immune system of the body is primarily mediated by white blood cells (leukocytes).
Among these,$B$-lymphocytes are a specific type of white blood cell responsible for the production of antibodies.
When $B$-lymphocytes encounter an antigen,they differentiate into plasma cells,which then secrete large quantities of antibodies into the blood and lymph to neutralize the pathogen.
$Eosinophils$,$Neutrophils$,and $Basophils$ are primarily involved in non-specific immune responses like phagocytosis or inflammatory reactions,but they do not produce antibodies.