Explanation

• Antonie van Leeuwenhoek is known as the Father of Microbiology.
• He was the first to observe and describe microorganisms using a microscope.
• He observed microscopic organisms in 1674.
• His discoveries included bacteria, protozoa, and other microscopic life forms.

Last verified on 05-09-2026

Explanation

Explanation

• Allergy is an abnormal immune response to harmless substances like dust or pollen.
• It occurs when the body reacts excessively to an allergen.
• This reaction involves the immune system producing antibodies.
• Thus, allergy is mainly due to an antigen–antibody reaction.

Last verified on 23-04-2026

Explanation

• The normal body temperature is: 37°C.
• The average normal body temperature is generally accepted as 98.6°F (37°C).
• A temperature over 100.4°F (38°C) means you have a fever.

Additional Information:

• Hypothermia is the term used for temperature less than 36.50°C.
• Mild Pyrexia is the term used for temperature (99-100°F).
• Moderate Pyrexia is the term used for temperature (100-103°F).
• Severe Pyrexia is the term used for temperature (103-105°F).

Explanation

• O⁻ (O Negative) is the universal donor blood group.
• It can be transfused to A, B, AB, and O blood groups.
• O⁻ blood lacks A, B, and Rh (D) antigens.

Additional information:

• Universal Recipient: AB⁺ (AB Positive)
• ABO Blood Groups: A, B, AB, O
• Rh Types: Positive (+) and Negative (−)
• Total Common Blood Groups: 8 (A⁺, A⁻, B⁺, B⁻, AB⁺, AB⁻, O⁺, O⁻)

Last verified on 14-07-2026