What is glycogen ? How is it different from starch?
Solution and Explanation
Glycogen is a carbohydrate (polysaccharide). In animals, carbohydrates are stored as glycogen.
Starch is a carbohydrate consisting of two components - amylose (15 - 20%) and amylopectin (80 - 85%).
However, glycogen consists of only one component whose structure is similar to amylopectin. Also, glycogen is more branched than amylopectin.
Top Questions on Biomolecules
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(a) HCN
(b) Br\(_2\) water- CBSE CLASS XII - 2025
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- Which of the following statements is not true about glucose?
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- Sweetest sugar is:
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- Write chemical equations of two methods of preparation of glucose. How will you obtain saccharic acid and gluconic acid from glucose?
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Questions Asked in CBSE CLASS XII exam
- A rectangular glass slab ABCD (refractive index 1.5) is surrounded by a transparent liquid (refractive index 1.25) as shown in the figure. A ray of light is incident on face AB at an angle \(i\) such that it is refracted out grazing the face AD. Find the value of angle \(i\).
- CBSE CLASS XII - 2025
- Refraction
Alexia Limited invited applications for issuing 1,00,000 equity shares of ₹ 10 each at premium of ₹ 10 per share.
The amount was payable as follows:- On application ₹ 9 per share (Including premium ₹ 6 per share)
- On allotment ₹ 8 per share (Including premium ₹ 4 per share)
- On first and final call ₹ 3 per share.
Applications were received for 1,50,000 equity shares and allotment was made to the applicants as follows:
Category A: Applicants for 90,000 shares were allotted 70,000 shares.
Category B: Applicants for 60,000 shares were allotted 30,000 shares.
Excess money received on application was adjusted towards allotment and first and final call.
Shekhar, who had applied for 1200 shares failed to pay the first and final call. Shekhar belonged to category B.
Pass necessary journal entries for the above transactions in the books of Alexia Limited. Open calls in arrears and calls in advance account, wherever necessary.- The firm of Amish, Nitish and Misha, who have been sharing profits in the ratio of 2 : 2 : 1, have existed for some years. Misha wanted that she should get equal share in the profits with Amish and Nitish and she further wished that the change in the profit sharing ratio should come into effect retrospectively for the last three years. Amish and Nitish had agreement for this.
The profits for the last three years were: 2021–22 ₹ 1,15,000; 2022–23 ₹ 1,24,000; 2023–24 ₹ 2,11,000
Show adjustment of profits by means of a single adjustment journal entry. Show your working clearly.- CBSE CLASS XII - 2025
- Profit sharing ratio
- Two coils ‘1’ and ‘2’ are placed close to each other as shown in the figure. Find the direction of induced current in coil ‘1’ in each of the following situations, justifying your answers:
(a) Coil ‘2’ is moving towards coil ‘1’.
(b) Coil ‘2’ is moving away from coil ‘1’.
(c) The resistance connected with coil ‘2’ is increased keeping both the coils stationary.
- CBSE CLASS XII - 2025
- Electromagnetic induction
- Write the mathematical forms of three postulates of Bohr’s theory of the hydrogen atom. Using them prove that, for an electron revolving in the \( n \)-th orbit,
(a) the radius of the orbit is proportional to \( n^2 \), and
(b) the total energy of the atom is proportional to \( \frac{1}{n^2} \).- CBSE CLASS XII - 2025
- Atomic Structure
Concepts Used:
Polysaccharides
Polysaccharides are the most abundant hydrocarbons that exist in our food. They are long chains of hydrocarbons inclusive of smaller units called monosaccharides or monomers, related to each other through glycosidic linkages. Cellulose, starch, chitin, and glycogen are the most common polysaccharides found in food.
Characteristics of Polysaccharides:
- Desiccation does not cause Polysaccharides to structure crystals.
- They do not have a candied flavor.
- Water cannot infiltrate the molecules due to the numerous hydrogen bonds, making them hydrophobic.
- They are osmotically inactive and close-packed inside the cells. Many are water-insoluble.
- They are collections of hydrogen, carbon, and oxygen. 2:1 is the ratio of hydrogen to oxygen.
- They are carbohydrates with a molecular weight comparatively more excessive than other compounds. It is also possible to extract a white powder out of it.
Types of Polysaccharides:
- Homopolysaccharides
- Heteropolysaccharides