Important Questions Class 12 Biology Chapter 7 Human Health And Disease

Important Questions Class 12 Biology Chapter 7 focus on the chapter Human Health and Disease, one of the most relevant and concept-based units in the Class 12 Biology syllabus.

With the Class 12 Biology board exam scheduled for February 25, 2026, students must prioritise revision and practice high-weightage topics from this chapter.

The chapter explains pathogens, immunity, common diseases, AIDS, cancer, drug abuse, and immune responses, all of which are frequently tested in board exams through short answers, long answers, case-based questions, and MCQs. Practicing Human Health And Disease Class 12 Important Questions ensures clarity of medical concepts and improves answer-writing precision.

Important Questions Class 12 Biology Chapter 7 Human Health And Disease

The chapter Human Health and Disease is highly important for the board exam because it connects biological concepts with real-life health issues. Questions often test understanding of immunity mechanisms, transmission of diseases, and prevention strategies.

Students should thoroughly practice Human Health And Disease Class 12 Important Questions and revise definitions, differences, and examples carefully to secure full marks.

Below are exam-oriented Important Questions Class 12 Biology Chapter 7 covering short answers, long answers, and conceptual explanations.

1. The disease chikungunya is transmitted by:

(1) house fly
(2) Aedes mosquito
(3) cockroach
(4) female Anopheles

Ans. (2) Aedes mosquito

2. When a healthy person is diagnosed as unhealthy by a psychiatrist, the reason could be that:
(1) the patient was not efficient at his work
(2) the patient was not economically prosperous
(3) the patient shows behavioural and social maladjustment
(4) he does not take an interest in sports

Ans. (3) the patient shows behavioural and social maladjustment

3. Transplantation of tissues/organs to save certain patients often fails due to the rejection of such tissues/organs by the patient. Which type of immune response is responsible for such rejections?

(1) auto-immune response
(2) humoral immune response
(3) physiological immune response
(4) cell-mediated immune response

Ans. (4) cell-mediated immune response

4. When the ELISA test was conducted on an immune-suppressed person, he tested positive for a pathogen.
(a) Identify the disease the patient is suffering from.
(b) Name the causative entity.
(c) Mention the cells of the body that are attacked by the pathogen.

Ans. (a) The patient is suffering from AIDS
(b) It is caused by the Human Immunodeficiency Virus (HIV)
(c) It affects a type of white blood cells called CD4 cells

5. Mention the site in the body where the B-cells and T-cells are formed. Give one difference between them.

Ans. Both the B-cells and T-cells are formed in the bone marrow. They differ in the site of maturation. B-cells mature in the bone marrow whereas the T-cells mature in the thymus.

6. List the preventive barriers that protect the body against microbial bacteria entering the gut through the food consumed. Name the immunity type observed in this case.

Ans. Following are the barriers:

• Lysozyme present in the saliva

• Presence of acid (HCl) in the stomach

• Mucous coating the epithelial lining in the gut Innate immunity is observed here.

7. Answer the following questions on the outline structure of a drug shown below:

(a) Name the group of drugs this structure represents.

(b) List the modes of consumption of this drug

(c) Which organ of the body is affected by the consumption of this drug?

Ans. (a) Cannabinoids

(b) Oral Ingestion or inhalation

(c) The cardiovascular system and the heart are affected

8. How to detect cancer? What are a few approaches to treat cancer?

Ans. Cancer can be detected at early stages and early detection is essential. Following are a few can diagnosis and detection areas:

• Tests for increases cell counts(blood cancer)

• Histo-pathological and biopsy of blood/tissues/bone marrow

• Radiography, CT, MRI to detect cancer of internal organs

• Identification of cancer-specific antigens

• Application of molecular biology techniques to detect genes with inherited susceptibility to a few cancers

Treatment of cancer: Listed below are a few approaches that can be used to treat cancer.

• Surgery to remove the tumour

• Immunotherapy to boost the killing of cancer cells

• Radiotherapy to kill cancerous cells

• Chemotherapy

• Administration of biological response mediators such as α-interferons that activate the immune system thus helping in destroying the tumour

9. Explain why excessive dosage and abusive usage of drugs such as amphetamines, LSD and barbiturates used to treat mental illness, are considered harmful? What are the major effects of the usage of drugs in humans?

Ans. Its harmful effects are:

• Shakiness, anxiety, sweating and nausea, loss of mind control

• Vandalism, violence and reckless behaviour

• Fluctuations in appetite and weight, lack of interest in personal hygiene

• Isolation, depression, withdrawal, aggressive behaviour, fatigue

• Social adjustment problems

• Severe and life-threatening withdrawal symptoms

• Excessive drug dosage can lead to coma and eventually death may occur due to respiratory failure, cerebral haemorrhage or heart failure

10. State the behavioural changes observed in an alcohol addict and remedial measures to overcome the problem.

Ans. Following changes are observed:

• Alcohol drinks are costly, it may deprive the family of their basic needs

• Drinking is associated with crimes and dissolution of cultural and moral inhibitions.

• Few corrupt practices and violence are often directly or indirectly related to alcohol consumption

Remedial measures:

• Avoid getting influenced by pressure from peers

• Counselling and education aids in overcoming issues like stress, failure and disturbance

• Seek aid from family and peers

• Staying aware of danger signals, if one finds himself amidst a group of people consuming alcohol.

• Seeking medical or professional help is one of the resorts for people suffering from addiction, to lead a healthy and normal life.

Last-Minute Revision Tips for Human Health And Disease

With the Biology board exam approaching, follow these quick strategies:

1. Revise key definitions such as immunity, vaccination, pathogen, and allergen.

2. Focus on differences between active and passive immunity.

3. Memorize transmission methods of common diseases.

4. Practice writing short answers in point-wise format.

5. Solve previously practiced Human Health And Disease Mcq sets.

6. Avoid starting new topics; focus only on revision of Important Questions Class 12 Biology Chapter 7.

How to Score Full Marks in CBSE 12th Biology Chapter 7

• Use correct biological terminology in answers.

• Write structured answers with headings and subheadings.

• Include examples like HIV, malaria parasite, and cancer cells.

• Practice diagram-based explanations related to immune response.

• Revise NCERT line by line for better conceptual clarity.

• Allocate at least one dedicated revision session for Human Health and Disease before the exam.