Practice MCQ Questions and answers on Biology-GK

71

One day you wake with a sore throat and a runny nose. Your doctor takes a swab from your throat, sends it to a lab, and telephones you the next day to say that antibiotic will not help you get better. Which of the following is the most likely reason for the doctor's statement?

A) Having waited a day, it is too late to take an antibiotic B) You need an antiseptic, not an antibiotic C) You need to be vaccinated instead of taking an antibiotic D) You are infected by a virus

Discuss

Answer & Solution

Answer: Option D

Solution:

The most likely reason for the doctor's statement is that the person is infected by a virus.

72

Plants that grow under average temperature and moisture are called:

A) halophytes B) hydrophytes C) mesophytes D) xerophytes

Discuss

Answer & Solution

Answer: Option C

Solution:

Plants that grow under average temperature and moisture are called mesophytes.

73

Oxyreductases, transferases, hydrolases, lyases, isomerases and ligases are all classes of

A) hormones B) enzymes C) proteins D) vitamins

Discuss

Answer & Solution

Answer: Option B

Solution:

Oxyreductases, transferases, hydrolases, lyases, isomerases and ligases are all classes of enzymes.

74

Mutation is

A) a factor responsible for plant growth B) a change which affects the offspring of F₂ generation only C) a change that is inherited D) a change which affects the parents

Discuss

Answer & Solution

Answer: Option C

Solution:

A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.

75

Pollination by wind is called

A) anemophily B) hydrophily C) zoophily D) entomophily

Discuss

Answer & Solution

Answer: Option A

Solution:

Anemophily is the process when pollen is transported by air currents from one individual plant to another. About 12% of the world's flowering plants are wind-pollinated, including grasses and cereal crops, many trees, and the infamous allergenic ragweeds.

76

Pollen grains in plants are produced in

A) roots B) leaves C) flower D) stem

Discuss

Answer & Solution

Answer: Option C

Solution:

Pollen grains in plants are produced in flower.

77

Nitrogen is fixed in ecosystems in ways stated below. Which one of the statements below is false?

A) By cyanobacteria B) By electrical discharges in the atmosphere C) By industrially synthesised fertilizer D) By denitrification

Discuss

Answer & Solution

Answer: Option D

Solution:

Nitrogen is not fixed in ecosystems by denitrification.

78

Ptyalin is an enzyme produced in the

A) salivary glands B) pituitary glands C) thyroid glands D) pancreas

Discuss

Answer & Solution

Answer: Option A

Solution:

Ptyalin is produced by the salivary glands, whereas pancreatic amylase is secreted by the pancreas into the small intestine.

79

Mycobacterium leprae causes leprosy, Corynebacterium diphtheria causes diphtheria and Vibrio comma causes

A) tetanus B) influenza C) cholera D) typhoid

Discuss

Answer & Solution

Answer: Option C

Solution:

Vibrio cholerae (also Kommabacillus) is a gram negative comma-shaped bacterium with a polar flagellum that causes cholera in humans

80

Biotic component of the environment does not include-

A) Soil system B) Animal system C) Micro-organism system D) Plant system

Discuss

Answer & Solution

Answer: Option A

Solution:

Animal, Micro organism and Plants are biotic components of the environment while soil along with other landforms are non-biotic components of the environment.