AIDS Questions in English

(A) $HIV$ (Human Immunodeficiency Virus) is a retrovirus.
It contains two identical strands of single-stranded $RNA$ as its genetic material.
Upon entering the host cell,the viral enzyme reverse transcriptase converts this $RNA$ into $DNA$,which then integrates into the host genome.

(A) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the Human Immunodeficiency Virus $(HIV)$.
$HIV$ specifically targets and infects helper $T$-lymphocytes ($CD4^+$ cells).
As the virus replicates within these cells,it leads to their progressive destruction.
Since helper $T$-lymphocytes are crucial for coordinating the immune response,their depletion severely weakens the body's immune system,making the individual susceptible to opportunistic infections.

(C) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the $HIV$ virus.
It spreads through the exchange of body fluids such as blood,semen,vaginal secretions,and breast milk.
It does not spread through casual physical contact,sharing personal items like towels,or using common household objects like toothbrushes.
Therefore,options $C$ and $D$ are both correct in the context of non-transmission,but in standard multiple-choice questions of this type,sharing personal items like towels or toothbrushes is considered safe regarding $HIV$ transmission.
However,since $AIDS$ is not transmitted by casual contact or sharing personal hygiene items,both $C$ and $D$ are technically correct answers. Given the standard format,we identify that $AIDS$ is not spread by casual contact.

(D) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the $HIV$ virus.
It spreads through:
$1$. Sexual contact with an infected person.
$2$. Transfusion of $HIV$-contaminated blood and blood products.
$3$. Sharing infected needles or syringes.
$4$. From an infected mother to her child through the placenta.
$AIDS$ does not spread through casual physical contact,sharing personal items like toothbrushes (unless contaminated with fresh infected blood),or using sterile needles.
Therefore,the use of sterile needles does not spread $AIDS$.

(C) The $AIDS$ virus is known as the Human Immunodeficiency Virus $(HIV)$.
$HIV$ belongs to the group of viruses called retroviruses.
Retroviruses contain $RNA$ as their genetic material,which is enclosed within a protein coat (capsid).
Therefore,the $AIDS$ virus consists of $RNA$ along with its associated proteins.

(C) After entering the human body,the $HIV$ virus enters into macrophages.
Inside the macrophages,the viral $RNA$ genome replicates to form viral $DNA$ with the help of the enzyme reverse transcriptase.
This viral $DNA$ gets incorporated into the host cell's $DNA$ and directs the infected cells to produce virus particles.
Thus,macrophages continue to produce virus particles and act like an $HIV$ factory.

(A) The enzyme $reverse \text{ } transcriptase$ is a characteristic feature of retroviruses.
$HIV$ (Human Immunodeficiency Virus) is a well-known retrovirus that uses $reverse \text{ } transcriptase$ to convert its single-stranded $RNA$ genome into double-stranded $DNA$ inside the host cell.
$HTLV-1$ (Human $T$-cell Lymphotropic Virus type $1$) is also a retrovirus and contains this enzyme.
However, in the context of standard biology curriculum questions regarding $HIV$ and $AIDS$, $HIV$ is the primary example.
Given the options provided, both $HIV$ and $HTLV-1$ are retroviruses. In many competitive examinations, $HIV$ is the intended answer for this specific question.

(A) Assertion $A$ is true because $AIDS$ ($Acquired$ $Immuno$ $Deficiency$ $Syndrome$) severely weakens the immune system,making the patient susceptible to opportunistic infections.
Reason $R$ is true because the $HIV$ virus specifically targets and destroys helper $T$-lymphocytes ($CD4^+$ cells),which are essential for coordinating the immune response.
Since the reduction in helper $T$-lymphocytes is the direct cause of the immune system's failure,Reason $R$ correctly explains Assertion $A$.

(D) $HIV$ (Human Immunodeficiency Virus) is primarily transmitted through the following ways:
$1$. Sexual contact with an infected person.
$2$. Transfusion of contaminated blood and blood products.
$3$. Sharing infected needles as in the case of intravenous drug abusers.
$4$. From an infected mother to her child through the placenta.
Among the given options,sexual contact is a known mode of transmission for $HIV$,whereas tears,saliva,and urine do not transmit the virus.

(C) The provided figure represents the structure of the $HIV$ virus. In this diagram,'$A$' points to the glycoprotein spikes (specifically gp120) on the surface of the viral envelope. These glycoproteins act as receptor-binding proteins that allow the virus to attach to the host cell's CD4 receptors. Therefore,the correct option is '$C$'.

(A) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the Human Immunodeficiency Virus $(HIV)$.
$HIV$ specifically targets and destroys helper $T$-lymphocytes,which are crucial components of the human immune system.
Due to the depletion of these cells,the body's immune system becomes severely compromised,leading to the development of various opportunistic infections and cancers.
Because the immune system is severely weakened,the disease is considered incurable and fatal,making $A$ a true statement.
Since the destruction of the immune system by $HIV$ is the direct biological reason why $AIDS$ is a fatal and severe condition,$R$ is the correct explanation for $A$.

(B) $HIV$ (Human Immunodeficiency Virus) is the causative agent of $AIDS$.
$1$. $ELISA$ (Enzyme-Linked Immunosorbent Assay) is the primary screening test used to detect $HIV$ antibodies in the blood.
$2$. $WB$ $Test$ (Western Blot) is a highly specific confirmatory test used to verify the presence of $HIV$ antibodies after a positive $ELISA$ result.
$3$. $VB$ $Test$ and $ALISA$ are not standard diagnostic procedures for $HIV$.
Therefore,the correct methods are $(i)$ and $(ii)$.

(B) An individual who is infected with $HIV$ but does not yet show symptoms of $AIDS$ is referred to as an $HIV$ carrier or an $HIV$ positive individual. In the context of the options provided,$HIV$ carrier is the most appropriate term for a person who harbors the virus and can transmit it to others while remaining asymptomatic.

(B) The sequence of events in $HIV$ infection is as follows:
$1$. After entering the body,$HIV$ first enters into macrophages $(IV)$.
$2$. Inside the macrophages,the viral $RNA$ genome is replicated to form viral $DNA$ by the enzyme reverse transcriptase $(III)$.
$3$. This viral $DNA$ then gets incorporated into the host cell's $DNA$ $(I)$.
$4$. The macrophages continue to produce virus particles,acting like an $HIV$ factory $(VI)$.
$5$. Subsequently,the virus enters $T_H$ lymphocytes and replicates to produce progeny viruses $(II)$.
$6$. This leads to a progressive decrease in the number of $T_H$ lymphocytes in the body,eventually causing their destruction $(V)$.
Therefore,the correct sequence is $IV, III, I, VI, II, V$.

(D) $HIV$ (Human Immunodeficiency Virus) is a member of a group of viruses called retroviruses.
These viruses have an envelope enclosing the $RNA$ genome.
$HIV$ does not contain $DNA$ as its genetic material; instead,it contains $RNA$.
Upon infection,the viral $RNA$ is converted into viral $DNA$ by the enzyme reverse transcriptase,which then incorporates into the host cell's $DNA$ to direct the synthesis of new viral particles.
Therefore,the statement that it contains $DNA$ as its genetic material is incorrect.

(C) $HIV$ stands for $Human$ $Immunodeficiency$ $Virus$.
It is the retrovirus that causes $AIDS$ ($Acquired$ $Immuno$ $Deficiency$ $Syndrome$).
This virus attacks the $CD4+$ $T$-helper cells of the human immune system,leading to a progressive decline in immune function.

(A) The $HIV$ (Human Immunodeficiency Virus) belongs to the group of viruses known as retroviruses.
Retroviruses are characterized by the presence of an $RNA$ genome that is reverse-transcribed into $DNA$ inside the host cell using the enzyme reverse transcriptase.
$HIV$ specifically targets $CD4+$ $T$-helper cells,leading to the progressive failure of the immune system,a condition known as $AIDS$ (Acquired Immuno Deficiency Syndrome).

(A) The $HIV$ (Human Immunodeficiency Virus) primarily targets and enters helper $T$-lymphocytes ($CD4^+$ cells).
Once inside,the virus uses the cell's machinery to replicate,eventually leading to the destruction of these cells.
This depletion of helper $T$-cells severely weakens the immune system,making the body susceptible to opportunistic infections.
While $HIV$ can also infect macrophages,the primary and most significant impact on the immune system's function is the destruction of helper $T$-lymphocytes.

(A) The $HIV$ (Human Immunodeficiency Virus) primarily targets the immune system of the human body.
Upon entering the body,the virus first infects macrophages,which act as a reservoir for the virus.
Subsequently,the virus enters $T_H$ cells (Helper $T$-cells),where it replicates and produces progeny viruses.
This leads to a progressive decrease in the number of $T_H$ cells in the body,severely weakening the immune system.
Therefore,the correct cells affected are $T_H$ cells $(i)$ and macrophages $(iv)$.

(A) The first case of $HIV$ infection in India was reported in $1986$ among commercial sex workers in Chennai,Tamil Nadu. Since then,the virus has spread across various parts of the country.

(A) $AIDS$ stands for $Acquired$ $Immunodeficiency$ $Syndrome$.
It is a chronic,potentially life-threatening condition caused by the $Human$ $Immunodeficiency$ $Virus$ $(HIV)$.
$Acquired$ means it is not inherited but acquired during a person's lifetime.
$Immunodeficiency$ refers to the weakening of the immune system.
$Syndrome$ refers to a group of symptoms that occur together.

(C) $AIDS$ (Acquired Immuno Deficiency Syndrome) is a disease caused by the $HIV$ (Human Immunodeficiency Virus).
$AIDS$ spreads primarily through the following modes:
$1$. Unprotected sexual contact with an infected person.
$2$. Transfusion of $HIV$-contaminated blood or blood products.
$3$. Sharing of infected needles or syringes.
$4$. From an infected mother to the fetus through the placenta.
$AIDS$ does not spread through handshaking or casual social contact. Therefore,among the given options,the transfusion of $HIV$-infected blood is the most accurate answer.

(A) $HIV$ (Human Immunodeficiency Virus) primarily targets and infects helper $T$-lymphocytes (also known as $CD4^+$ $T$-cells).
Upon entering the body,the virus replicates inside these helper $T$-cells,leading to their progressive destruction.
As the number of helper $T$-cells decreases,the immune system becomes severely compromised,making the body susceptible to opportunistic infections.
Therefore,$HIV$ specifically causes a reduction in helper $T$-cells.

(B) $HIV$ (Human Immunodeficiency Virus) specifically targets and infects $T_H$ cells (Helper $T$-lymphocytes).
As the virus replicates within these cells,it leads to their destruction.
Consequently,the count of $T_H$ cells in the blood progressively decreases,which severely weakens the body's immune system,leading to the condition known as $AIDS$.

(C) After entering the body of the person,the $HIV$ virus enters into macrophages where $RNA$ genome of the virus replicates to form viral $DNA$ with the help of the enzyme reverse transcriptase.
This viral $DNA$ gets incorporated into the host cell's $DNA$ and directs the infected cells to produce virus particles.
The macrophages continue to produce virus and in this way acts like an $HIV$ factory.
Simultaneously,$HIV$ enters into helper $T$ lymphocytes ($T_H$ cells),replicates and produces progeny viruses.
The progeny viruses released in the blood attack other helper $T$ lymphocytes.
This leads to a progressive decrease in the number of helper $T$ lymphocytes in the body of the infected person.

(A) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the Human Immunodeficiency Virus $(HIV)$.
$HIV$ specifically targets and infects helper $T$-lymphocytes ($CD4^+$ cells).
As the virus replicates within these cells,it leads to the destruction of helper $T$-lymphocytes.
Since helper $T$-cells are crucial for coordinating the immune response,their depletion results in a severely compromised immune system,making the body susceptible to opportunistic infections.

(C) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the Human Immunodeficiency Virus $(HIV)$.
It is a severe,incurable,infectious,and fatal disease that weakens the immune system by destroying $CD4+$ $T$-helper cells.
While cancer is severe and can be fatal,it is not infectious.
Typhoid and malaria are infectious but are curable with appropriate medical treatment.

(A) $AIDS$ stands for Acquired Immunodeficiency Syndrome.
It is a chronic, potentially life-threatening condition caused by the Human Immunodeficiency Virus $(HIV)$.
$HIV$ damages the immune system, interfering with the body's ability to fight infection and disease.

(A) $AIDS$ (Acquired Immuno Deficiency Syndrome) was first reported in the $USA$ in the year $1981$. Since then,it has spread globally,becoming a major public health challenge.

(C) According to the $NCERT$ textbook for Class $12$ Biology (Chapter: Human Health and Disease),since the first report of $AIDS$ in $1981$,it has killed more than $25$ million people worldwide. Therefore,the correct option is $C$.

(D) The first case of $AIDS$ ($Acquired$ $Immuno$ $Deficiency$ $Syndrome$) in India was reported in the year $1986$ in the state of Tamil Nadu. It was identified among female sex workers in Chennai.

(A) The first case of $AIDS$ (Acquired Immuno Deficiency Syndrome) in India was reported in $1986$.
$AIDS$ is caused by the Human Immunodeficiency Virus $(HIV)$,
which attacks the body's immune system,specifically the $CD4$ positive $T$-helper cells.
Since its first detection in India,the government has taken various measures to control its spread through awareness programs and screening.

(B) The causative agent of $AIDS$ (Acquired Immuno Deficiency Syndrome) is the Human Immunodeficiency Virus $(HIV)$. $HIV$ belongs to a group of viruses called retroviruses,which have an $RNA$ genome enclosed within a protein envelope. These viruses use the enzyme reverse transcriptase to convert their $RNA$ into $DNA$,which then integrates into the host cell's genome.

(B) $HIV$ stands for Human Immunodeficiency Virus.
It is a retrovirus that attacks the human immune system,specifically targeting $CD4+$ $T$-helper cells.
Over time,the destruction of these cells leads to Acquired Immunodeficiency Syndrome $(AIDS)$.

(A) After entering the human body,the $HIV$ virus first enters macrophages,where it replicates and produces viral progeny. These macrophages act as an $HIV$ factory. Subsequently,the virus enters helper $T$-lymphocytes ($T_H$ cells) in the blood,where it continues to replicate and produce viral progeny. This leads to a progressive decrease in the number of helper $T$-lymphocytes in the infected person's body.

(D) The question refers to the replication cycle of retroviruses (like $HIV$) within host cells such as macrophages.
Upon entering the macrophage,the viral $RNA$ genome is converted into $DNA$ by the enzyme $Reverse$ $transcriptase$.
This $DNA$ then incorporates into the host genome to direct the synthesis of new viral particles.
Therefore,the correct enzyme is $Reverse$ $transcriptase$.

(C) After entering the human body,the $HIV$ virus enters into macrophages.
In the macrophages,the $RNA$ genome of the virus replicates to form viral $DNA$ with the help of the enzyme reverse transcriptase.
These macrophages continue to produce virus particles and thus act like an $HIV$ factory.
Therefore,macrophages are known as the factory for $HIV$.

(A) After entering the human body,the $HIV$ virus enters into macrophages where $RNA$ genome of the virus replicates to form viral $DNA$ with the help of the enzyme reverse transcriptase.
This viral $DNA$ gets incorporated into the host cell's $DNA$ and directs the infected cells to produce virus particles.
The macrophages continue to produce virus and in this way act like an $HIV$ factory.
Simultaneously,$HIV$ enters into helper $T$-lymphocytes ($T_H$ cells),replicates,and produces progeny viruses.
The progeny viruses released in the blood attack other helper $T$-lymphocytes.
This leads to a progressive decrease in the number of helper $T$-lymphocytes in the body of the infected person.

(B) After entering the human body,the $HIV$ virus enters macrophages where $RNA$ genome of the virus replicates to form viral $DNA$ with the help of the enzyme reverse transcriptase.
Macrophages continue to produce virus particles and thus act like an $HIV$ factory.
Simultaneously,$HIV$ enters helper $T$-lymphocytes ($T_H$ cells),replicates,and produces progeny viruses.
The progeny viruses released in the blood attack other helper $T$-lymphocytes.
This leads to a progressive decrease in the number of helper $T$-lymphocytes in the body of the infected person.

(D) $HIV$ (Human Immunodeficiency Virus) primarily targets and infects $T$-helper lymphocytes ($CD4^+$ cells).
As the virus replicates within these cells,it leads to their destruction,causing a significant decrease in the number of $T$-lymphocytes.
This depletion of the immune system makes the body susceptible to various infections,leading to symptoms such as persistent fever,significant weight loss,and chronic diarrhea.
Therefore,all the listed effects are characteristic of an $HIV$ infection.

(D) $AIDS$ (Acquired Immuno Deficiency Syndrome) is caused by the $HIV$ virus. It is transmitted through the following ways:
$1$. Sexual contact with an infected person.
$2$. Transfusion of $HIV$-contaminated blood and blood products.
$3$. Sharing of infected needles or syringes.
$4$. From an infected mother to her child through the placenta.
$5$. Transplantation of infected organs.
Therefore,all the given options are correct modes of transmission.

(B) $AIDS$ is caused by the Human Immunodeficiency Virus $(HIV)$.
It is transmitted through the exchange of body fluids,specifically blood,semen,vaginal secretions,and breast milk.
$1$. Sharing of used syringes or needles,blood transfusion,and organ transplantation are known modes of transmission because they involve the direct transfer of infected blood or body fluids.
$2$. $AIDS$ does $NOT$ spread through casual physical contact,such as shaking hands,hugging,or sharing clothes,utensils,food,or living spaces with an infected person.
Therefore,option $B$ is the correct answer.

(B) Individuals infected with $HIV$ are generally classified into $3$ clinical categories based on the progression of the disease and the $CD4+$ $T$-lymphocyte count:
$1$. Category $A$: Asymptomatic $HIV$ infection or persistent generalized lymphadenopathy.
$2$. Category $B$: Symptomatic conditions that are not included in category $C$ but are attributed to $HIV$ infection or indicate a defect in cell-mediated immunity.
$3$. Category $C$: $AIDS$-indicator conditions (severe immunosuppression).

(A) $ARC$ ($AIDS$-Related Complex) refers to a clinical state that precedes the development of full-blown $AIDS$. Symptoms of $ARC$ typically include persistent fever,night sweats,chronic diarrhea,significant weight loss (often called wasting syndrome),and fatigue. Bloody diarrhea is generally associated with specific opportunistic infections (like amoebiasis or severe bacterial dysentery) rather than being a primary diagnostic symptom of $ARC$ itself. Therefore,bloody diarrhea is not considered a characteristic symptom of $ARC$.

(A) In the context of $AIDS$ (Acquired Immuno Deficiency Syndrome),$ARC$ stands for $AIDS$-related complex.
It refers to a condition where a patient exhibits symptoms of $HIV$ infection that are not severe enough to be classified as full-blown $AIDS$ but are more advanced than the initial asymptomatic stage.
These symptoms may include fever,weight loss,fatigue,and lymphadenopathy.

(B) $ARC$ stands for $AIDS$ Related Complex. It is a clinical condition that occurs in individuals infected with $HIV$ (Human Immunodeficiency Virus) before the progression to full-blown $AIDS$ (Acquired Immunodeficiency Syndrome). It is characterized by symptoms such as fever,weight loss,lymphadenopathy,and fatigue.

(C) Full-blown $AIDS$ (Acquired Immuno Deficiency Syndrome) occurs when the $HIV$ virus severely damages the immune system,specifically by depleting $CD4^+$ $T$-helper cells.
As the immune system weakens,the body becomes susceptible to opportunistic infections and specific cancers.
Kaposi's sarcoma,which is a cancer of the blood vessels in the skin,is a characteristic clinical manifestation of advanced or full-blown $AIDS$.
Options $A$ and $B$ describe early stages or initial infection symptoms,while $D$ is not a specific diagnostic symptom of full-blown $AIDS$.

(B) $AIDS$ $(Acquired \text{ } Immuno \text{ } Deficiency \text{ } Syndrome)$ is caused by the $HIV$ $(Human \text{ } Immunodeficiency \text{ } Virus)$.
Currently,there is no vaccine available for $AIDS$,making statement $A$ correct.
$AIDS$ is a fatal disease and is considered completely incurable,making statements $C$ and $D$ correct.
Interferons are proteins produced by the body to fight viral infections,but they are not used for the treatment of $AIDS$. Antiretroviral drugs are used to manage $AIDS$. Therefore,statement $B$ is not correct for $AIDS$.

(D) $NACO$ (National $AIDS$ Control Organization) is a government organization in India that works to control the spread of $AIDS$ and create public awareness.
$NGOs$ (Non-Governmental Organizations) also play a significant role in educating the public and providing support to $AIDS$ patients.
$WHO$ (World Health Organization) is an international body that sets global standards and guidelines for $AIDS$ prevention and control.
Therefore,all these organizations are involved in creating awareness about $AIDS$.

(A) $NACO$ stands for National $AIDS$ Control Organization. It is a division of the Ministry of Health and Family Welfare that provides leadership to the $HIV$/$AIDS$ control programme in India through $35$ $HIV$/$AIDS$ Prevention and Control Societies.