COMPASSLearning
RegisterLogin

CBSE Class 12 · 2007 · All India · BiomoleculesShort Answer

WhatsApp Email
Answer the following questions briefly:
i) What are reducing sugars?
ii) What is meant by denaturation of a protein?
iii) How is oxygen replenished in our atmosphere?

Solution

(i) \textbf{Reducing sugars} carry a free (hemiacetal) carbonyl and reduce Fehling's and Tollens' reagents — glucose, maltose, lactose.
(ii) \textbf{Denaturation}: physical/chemical stress breaks the H-bonds of a protein's higher structure; it unfolds and loses activity, the sequence surviving.
(iii) Green plants replenish O through \textbf{photosynthesis}:

CBSE Class 12 Board · 2007 · All India · Subjective

Practise more: all CBSE board PYQs on Biomolecules →

More board questions on Biomolecules

  1. The specific sequence in which amino acids are arranged in a protein is called its:
    CBSE 2024View solution →
  2. Classify the following sugars into monosaccharides and disaccharides: galactose, glucose, lactose and maltose.
    CBSE 2024View solution →
  3. Case study — Vitamins: certain organic compounds required in small amounts in our diet whose deficiency causes specific diseases. Most vitamins cannot be synthesised in our body, but plants can synthesise almost all of them; gut bacteria produce some. The term 'vitamin' was coine …
    CBSE 2024View solution →
  4. Case study — Vitamins (same passage as above).
    OR (c) Why can't vitamin C be stored in our body? Name the disease caused by the deficiency of this vitamin.
    CBSE 2024View solution →
  5. Give the reaction of glucose with acetic anhydride. Which group's presence is confirmed by this reaction?
    CBSE 2023View solution →
  6. Give reasons for any three of the following observations:
    a) The pentaacetate of glucose does not react with hydroxylamine.
    b) Amino acids behave like salts.
    c) Water-soluble vitamins must be taken regularly in the diet.
    d) The two strands in DNA are complementary to each other.
    CBSE 2023View solution →