Page 44 - Innovator's Science-8

9. Which disease(s) among the following may spread if drinking water gets contaminated by the excreta
from an infected person? Hepa s A, Tuberculosis, Poliomyeli s, Cholera, Chickenpox.
Ans. The diseases that may spread if drinking water gets contaminated by the excreta from an infected
person are Hepa s A, Poliomyeli s, and Cholera.

10. When our body encounters a pathogen for the first me, the immune response is generally low, but on
exposure to the same pathogen again, the immune response by the body is much more compared to
the first exposure. Why is it so?

Ans. When our body faces a pathogen (like a virus or bacteria) for the first me, our immune system needs
me to:

• Iden fy the invader
• Create specific an bodies
• Build memory cells that remember the pathogen
This first reac on is called the primary immune response, and it's usually slow and weak.
When the same pathogen enters our body again:
• Our memory B cells quickly produce the correct an bodies
• Our memory T cells help destroy infected cells faster
This is called the secondary immune response, and it's faster, stronger, and more effec ve.

Put on your
Thinking cap
Problem Solving Skills
A. Darken the correct options in the OMR Sheet:
OMR Sheet
1. Which of the following is an example of a non-communicable disease?
a. Cholera b. Tuberculosis

c. Diabetes d. Influenza
2. ___________ is defined as a state of complete physical mental and social
Wrong Methods
well-being.
a. Health b. Mind set Correct Method
c. Society d. None of these

3. Keeping our surroundings clean helps to prevent the spread of: 1. a b c d
a. communicable diseases b. non-communicable 2. a b c d
c. genetic diseases d. lifestyle diseases
3. a b c d
4. We should say ‘No’ to the substances like ___________ .
a. wheat b. lime 4. a b c d
c. alcohol d. exercise 5. a b c d
5. All communicable disease are caused by ___________ .

a. pathogens b. vectors
c. blood pressure d. none of these

B. Fill in the blanks. Observational Skills
1. A disease affects the normal working of the body or ___________.

2. ___________ and ___________are communicable disease.
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Science-8