Name the primary and secondary lymphoid organs.
Solution and Explanation
A 'suitable gene' refers to a specific DNA segment which can be injected into the cells of the host body to produce specific proteins. This protein kills the specific disease- causing organism in the host body and provides immunity.
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Bittu and Chintu were partners in a firm sharing profit and losses in the ratio of 4 : 3. Their Balance Sheet as at 31st March, 2024 was as follows:
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The firm had stock of ₹ 20,000. Ajit took over 40% of the stock at a discount of 10% while the remaining stock was sold for ₹ 18,000.
Vibha was appointed to look after dissolution work for which she was allowed a remuneration of ₹ 16,000. Vibha agreed to bear the dissolution expenses. Actual dissolution expenses ₹ 15,000 were paid by Vibha.
Ajit’s loan of ₹ 45,000 was settled at ₹ 42,000.
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Concepts Used:
Types of Immunity
Immunity can be defined as the body's ability to guard itself against disease-causing organisms. In other words, it is the ability to resist infection by the action of particular antibodies. Our body has the ability to produce antibodies against pathogens and defend itself from diseases; therefore, we may come in contact with several viruses every day, but not get ill. This defense mechanism is therefore known as immunity.
The two major types of immunity are:
- Innate Immunity or Non-specific Immunity
- Acquired Immunity or Adaptive Immunity
Innate immunity
The immunity, which is present in an organism by birth is called innate Immunity. Innate immunity refers to the body’s defence system. For example, the skin, the barrier of the human body functions by protecting the entry of germs and other disease-causing pathogens.
Adaptive immunity
An individual acquires immunity after birth, hence is called adaptive or acquired immunity. Adaptive immunity develops throughout our lives. We acquire adaptive immunity when we are exposed to infectious diseases and allergies or when we are immunized against them with vaccines.
Passive immunity
Passive immunity is developed by antibodies that are produced outside the body. This immunity lasts for a short time. For example, antibodies present in a mother’s breast milk provide a baby with temporary immunity against the diseases.
Active Immunity
Active immunity is a type of adaptive immunity, which is developed due to the production of antibodies in one’s own body. This type of immunity occurs when we are in contact with the pathogen or its antigen.