Tag: biology

Questions Related to biology

Digestion of food
Which of the following match is correct?

  1. Renin Protein.

  2. Trypsin - Starch

  3. Invertase Sucrose

  4. Amylase Lactose


Correct Option: C
Explanation:

The correct answer is (c).

Which reserve a starving man first consumed?

  1. Fat

  2. Protein

  3. Glycogen

  4. Vitamin


Correct Option: C
Explanation:

Starvation mode is a state in which the body is responding to prolonged periods of low energy intake levels. The body responds to reduced energy intake by burning fat reserves and consuming muscle and other tissues. Specifically, the body burns fat after first exhausting the contents of the digestive tract along with glycogen reserves stored in muscle and liver cells. After prolonged periods of starvation, the body will utilize the proteins within muscle tissue as a fuel source.

The digestion of cellulose in rabbit and other herbivorous mammals takes place in

  1. Vermiform appendix

  2. Colon

  3. Caecum

  4. Ileum


Correct Option: C
Explanation:

Hindgut fermentation is a digestive process seen in monogastric herbivores, animals with a simple, single-chambered stomach. Cellulose is digested with the aid of symbiotic bacteria. The microbial fermentation occurs in the digestive organs that follow the small intestine: the large intestine and caecum.

Choose the wrong enzymatic reaction. 

  1. Sucrose $\overset{Invertase}{\rightarrow}$ Glucose + Fructose

  2. Lactose $\overset{Lactase}{\rightarrow}$ Glucose + Fructose

  3. Pepsinogen $\overset{HCI}{\rightarrow}$ Pepsin

  4. Maltose $\overset{Maltase}{\rightarrow}$ Glucose + Glucose


Correct Option: B
Explanation:

The correct answer is (b).

Sucrase is an enzyme found in:-

  1. saliva

  2. gastric juice

  3. intestinal juice

  4. pancreatic juice


Correct Option: C
Explanation:

Sucrase enzymes are located on the brush border of the small intestine. The enzymes catalyze the hydrolysis of sucrose to fructose and glucose. The sucrase enzyme invertase, which occurs more commonly in plants, also hydrolyzes sucrose but by a different mechanism

So, the correct option is 'Intestinal juice'

Distribution of clean and quality milk throughout the world has been made possible through work of

  1. Leeuwenhoek

  2. Koch

  3. Pasteur

  4. Blackman


Correct Option: C

Which of the following statements holds good with pasteurization?

  1. Pasteurization removes all the bacteria from milk.

  2. Pasteurization is a synonym for sterilization.

  3. Milk needs to be refrigerated even after pasteurization.

  4. Pasteurized milk causes lactose intolerance.


Correct Option: C
Explanation:

a) Pasteurization does not remove all bacteria from milk. It reduces the harmful active bacteria from the milk but it is unable to kill their spores which might erupt again under favourable conditions. 

b) Pasteurization is not a synonym for sterilization because of two processes are very different from each other when it comes to application. Pasteurization is the process where the milk is heated at to a specific temperature for a set period of time to reduce the bacterial population to prevent the spoilage and increase the shelf life. Sterilization kills all forms of living microorganism in the sample along with the spores of microorganism which cannot be done by the pasteurization.
c) Milk needs to be refrigerated even after pasteurization because refrigeration helps to keep the microorganism inactive for longer duration which increases the shelf life of the milk.
d) Pasteurized milk does not cause lactose intolerance because it does not affect or degrade the lactase enzyme which is responsible for lactose digestion in the humans.
So, the correct answer is 'Milk needs to be refrigerated even after pasteurization'.

The technique of developing pure culture of bacteria was developed by

  1. J. Lister

  2. L. Pasteur

  3. R. Koch

  4. A. V. Leeuwenhoek


Correct Option: C
Explanation:

A pure culture is a laboratory culture containing a single species of microorganisms. A pure culture was usually derived from a mixed culture (culture containing many species of organisms) by transferring a small sample into a new, sterile growth medium. Robert Koch developed solid culture media and the methods for obtaining pure cultures of bacteria.

So, the correct answer is 'R. Koch'.

Which famous biologist propounded the 'germ theory of disease'?

  1. Joseph Lister

  2. Thomas Syndenham

  3. Robert Koch

  4. Louis Pasteur


Correct Option: D
Explanation:

The more formal experiments on the relationship between germ and disease were conducted by Louis Pasteur between the year 1860 and 1864. He discovered the pathology of the puerperal fever and the pyrogenic vibrio in the blood, and suggested using boric acid to kill these microorganisms before and after confinement.

So, the corect option is D. ( Louis Pasteur)

Which of the following processes are used for increasing the shelf life of milk?

  1. Boiling

  2. Refrigerating

  3. Pasteurizing

  4. All of the above


Correct Option: D
Explanation:
  • Boiling increases the temperature of milk and kills many bacteria and thus increases the shelf life of milk when compared to raw milk.
  • Refrigeration lowers the temperatures of the growth medium ( milk) making it not suitable for bacterial growth and keeps milk fresh for a particular period of time.
  • Pasteurization is heating milk to high temperatures and cooling down quickly. This process kills many possible pathogens and increases the shelf life of milk to a better extent. (1 day to 2 days)
  • So the correct answer is 'Boiling, Refrigerating, and Pasteurizing'.