21.

Which one of the following is not a natural fibre?

• Silk
  
  

• Acrylic
  
  

• Cotton
  
  

• Jute

Ginger is the modification of

• root
  
  

• leaf
  
  

• stem
  
  

• fruit

True fruits develop from

• thalamus
  
  

• petal
  
  

• ovary
  
  

• sepal

Plant which reproduces by means of spores instead of seeds is

• coriander
  
  

• fern
  
  

• mustard
  
  

• petunia

The element, essential for synthesis of protein in plants, is

• copper
  
  

• nitrogen
  
  

• magnesium
  
  

• iron

Which one of the following is not a non-communicable disease?

• Hypertension
  
  

• Arthritis
  
  

• Rickets
  
  

• Cholera

Penicillin antibiotic is obtained from

• fungi
  
  

• algae
  
  

• bacteria
  
  

• blue-green algae

Which one of the following is not a source of energy?

• Protein
  
  

• Fat
  
  

• Vitamin
  
  

• Carbohydrate

The coding segment of DNA is called

• muton
  
  

• intron
  
  

• codon
  
  

• exon

Which of the following is not a micronutrient?

• Sodium
  
  

• Copper
  
  

• Silicon
  
  

• Calcium