Free Kingdom Prokaryotae MCQs with Answers

191. The structure of prokaryotes which is involved in attachment:

• A. Cilia
• B. Flagella
• C. Pili
• D. Cytoplasm

Explanation: Pili are hollow, nonhelical, filamentous appendages. They are primarily involved in a mating process between cells called conjugation. It helps the bacteria to stick to each other and to surfaces such as rocks in the flowing streams or to the lining of human intestines. Flagella helps with the motility of the bacteria while cilia are not present in prokaryotic cells. The cytoplasm also helps in the transport of material by cyclosis, the movement of cytoplasm.

192. Which one of the following edible products is widely pasteurized?

• A. Soft drinks
• B. Mango squash
• C. Milk
• D. Orange Juice

Explanation: Milk: This option is the correct answer. Milk is widely pasteurized to kill harmful bacteria and increase its shelf life. Pasteurization involves heating the milk to a specific temperature for a set period of time and then rapidly cooling it. This process helps to eliminate pathogenic bacteria while retaining the nutritional value of the milk.

193. Cyanobacteria are:

• A. Photoautotrophic bacteria
• B. Chemosynthetic bacteria
• C. Saprotrophic bacteria
• D. Parasitic bacteria

Explanation: Cyanobacteria synthesize their own food from inorganic substances and this fall into the category of photoautotrophs.

194. When the division of cells is in three planes, the arrangement is known as:

• A. Diplococcus
• B. Sarcina
• C. Streptococcus
• D. Staphylococcus

Explanation: Option A is incorrect because Division in one plane that form a pair of coocci is called diplococcus.Option B is correct since Division in three planes produces an arrangement called sarcina that is a cube of 8 cocci.Option C is incorrect because Streptococcus is division in one plane and has more than 2 cocci.Option D is incorrect because Staphylococcus is arrangement in which cocci are arranged in irregular , often grape like cluster.

195. Pasteurization technique is widely used for preservation of:

• A. Water
• B. Heat
• C. Milk products
• D. Vaccines

Explanation: Pasteurization is a technique to remove pathogenic organisms in certain foods and liquids. In water, bacteria is killed through the process of chlorination. Hence, the only remaining viable option is option C : Milk products.

196. A bacterium which has a group of two or more flagella inserted at one pole of the cell

• A. Monotrichous
• B. Peritrichous
• C. Lophotrichous
• D. Amphitrichous

Explanation: There are four types of flagellar arrangements based on the number and placement of flagella on the cell. These are, 1. Monotrichous - A single flagellum extends from one end of the cell. 2. Amphitrichous - A single flagellum or multiple flagella extend from two ends of the cell. 3.Lophotrichous - Tufts of flagella extend from one end or both ends of the cell. 4. Peritrichous - Multiple flagella randomly distributed over the entire bacterial cell. Thus, the correct answer is 'Lophotrichous.'

197. The following are sexual reproduction methods in bateria except

• A. Transformation
• B. Transduction
• C. Binary fission
• D. Conjugation

Explanation: In bacteria,genetic recombination takes place. Genetic recombination is primitive type of sexual reproduction. There are three types of genetic recombination: Transformation,Transduction, Conjugation.

198. Nitrifying bacteria belong to following group:

• A. Chemosynthetic
• B. Photosynthetic
• C. Parasitic
• D. Pathogenic

Explanation: The nitrifying bacteria of the soil are Nitrosomonas and Nitrobacter. They are called chemoautotrophs (chemosynthetic would be a general term) because they obtain energy from the oxidation of ammonium and nitrate ions.

199. The chemical substances that are used to inhibit the growth of micro organism on living surfaces, are called:

• A. Disinfectants
• B. Chemotherapeutics
• C. Vaccines
• D. Antiseptics

Explanation: Antiseptics are used to inhibit the growth of bacteria.

200. Which of the following provides resistance against high temperature?

• A. Cysts
• B. Spores
• C. Cell wall
• D. Capsules

Explanation: Endospores (spores withing the vegetative cells) are tough dormant structures that form inside the cell wall of certain types of bacteria, such as Bacillus. These tough capsules form in response to adverse conditions such as drought or high temperatures.