Level: F.Sc (Pre-Engg)
Class: 1st Year
Board: Punjab Textbook Board
Subject: Biology
Chapter 6: Kingdom Monera
Type: Short Questions
Author: Kiran Mehtab
Pages: 11
PDF Size: 2 MB
What temperatures are used to sterilize food and milk?
Food is sterilized by using high temperatures of 120° – 126°C obtained by heating under pressure for 12 to 90 minutes. Milk is pasteurized by heating at 71°C for 15 seconds or at 62°C for 30 minutes.
What are chemical methods used for microbial control?
One can use antiseptics, disinfectants, chemotherapeutic agents and antibiotics for microbial control.
What are disinfectants or what chemical agents are used for disinfection?
The important chemical agents used for disinfection are oxidising and reducing agents, for example, halogens and phenols, hydrogen peroxide, potassium per magnate, alcohol and formaldehyde etc. These chemicals inhibit the growth of vegetative cell. They are used on nonliving materials.
What chemical methods or substances are used for natural defence or in living tissues?
Chemotherapeutic agents and antibiotics work with natural defence and stop the growth of bacteria and other microbes. These are sulfonamides, tetracycline, penicillin, etc. They destroy or inhibit the growth of microorganisms in living tissues.