Question Discussion & Solution

The correct answer is Potato.

Modifications of Root

1. For storage of food
   • Roots are modified in some plants for storing reserve food materials.
   • These modified roots usually are swollen and assume different forms such as spindle-shaped, e.g., radish; top-shaped, e.g., beet, turnip; cone-like, e.g., carrot; indefinite shape, e.g., sweet potatoes.
   • Dahlia, Asparagus, Portulaca are some other examples of plants with modified roots for food storage.
2. Nodulated roots
   • The roots of pea and other leguminous plants have numerous swollen nodules on fine branches of roots.
   • These nodules are formed due to the symbiotic association of Rhizobium (bacterium) that live inside the root cortical cells of the roots.
   • They fix nitrogen and an active nodule is pink in colour.
3. For mechanical support
   • Roots are modified to provide mechanical support as seen in a banyan tree which has roots growing vertically/obliquely downwards (prop roots); sugarcane/maize in which roots arise from the nodes in the cluster at the base of the stem (stilt roots) and betel/black pepper in which nodes and internodes bear roots which help in climbing.
4. For gaseous exchange
   • Pneumatophores or breathing roots are found in plants growing in mangroves or swamps with saline water for exchange of gases.
   • They are erect peg-like structures with numerous pores through which air circulates e.g., Rhizophora mangle.

• Modifications of Stem

1. For storage of food
   • Stems get modified into underground structures for storage of food as seen in potato (tuber), ginger (rhizome), garlic (bulb), yam (corm).
   • Presence of an eye (node) in potato, distinct nodes with internodes and scaly leaves in ginger/yam, a cluster of roots at the base of the reduced stem in garlic/ onion, all indicate that these underground plant parts are modified stem.
2. For vegetative propagation
   • Plants besides reproducing sexually also propagate through vegetative parts.
   • For this purpose, stems may be modified into a runner (Cyanodon dactylon, Oxalis). Runners are slender prostrate branches arising from axillary buds;
   • stolon (e.g., mint, strawberry) which is a slender lateral branch arising from the base of the stem grows upward and then down to develop new daughter plants;
   • offset having a single long horizontal internode growing up to some distance and producing a tuft of leaves above and a cluster of roots below at the apex (Eichornia, Pistia) and
   • sucker, which arises from the underground part of the stem, grow obliquely and gives rise to a new shoot. (Chrysanthemum, Banana, Pineapple).
3. For protection
   • Some modified stem provides protection as thorns which are hard, pointed structures each representing a branch that arises from the axil of a leaf.
   • Thorns are found in plants like Duranta, Pomegranate, Acacia, Ber, Prosopis, Bougainvillea, Citrus, etc.
4. For support
   • Tendrils are modifications of the stem to provide support to plants, e.g., Vitis, passionflower, Bignonia etc.
5. For photosynthesis
   • Stems are also modified into Phylloclade, to facilitate photosynthesis.
   • Phylloclades are flattened/cylindrical stem or branches of unlimited growth (Cactus).

The correct answer is 6 years.

Key Points

• The  Council of States or Rajya Sabha is the upper house of the bicameral Parliament of India.
• Rajya Sabha is a permanent body and it can never dissolve.
• There is no tenure of Rajya Sabha whereas the member of Rajya Sahba has a tenure of 6 years.
• One-third of members of the Rajya Sabha retire every second year in a cyclic manner.
• Rajya Sabha-
  • As of 2021, the Rajya Sabha has a maximum membership of 245.
  • Out of 245, 233 are elected by the legislatures of the states and union territories using single transferable votes through Open Ballot and the President can appoint 12 members for their contributions to literature, art, science, and social services.
  • The potential seating capacity of the house (Rajya Sabha) is 250 (238 elected, 12 Nominated by the President of India), according to article 80 of the Constitution of India.
  • The Vice President of India is the ex-officio Chairman of the Rajya Sabha.

Important Points

• The Indian Parliament is the supreme legislative body of the Republic of India.
• The Parliament is a bicameral legislature composed of the President of India and 2 houses: the Lok Sabha and Rajya Sabha.
• The term of office of a Lok Sabha member is 5 years.
• The Indian Constitution provides that the maximum strength of Lok Sabha be 550 members.

Key Points

A binary tree is a tree data structure in which each node has at most two child nodes.

The number of subtrees of a node is called the degree of the node. In a binary tree, all nodes have degrees o, 1, and 2. 

The degree of a tree is the maximum degree of a node in the tree. A binary tree is of degree 2. The number of nodes of degree 2 in Tis "n-1".

Hence the correct answer is n-1.

The correct answer is Musca domestica.

• The scientific name of Housefly is Musca domestica.

Additional Information 

The correct answer is ​Sodium benzoate.

Key Points

• Sodium benzoate is a preservative that is most widely used in acidic foods such as salad dressings, carbonated drinks, jams and fruit juices, pickles, condiments, and yoghurt toppings.
• Food preservation is a method to protect food from unwanted microbial growth and is done to preserve food for a longer time.
• Sodium benzoate is a widely used preservative found in many foods and soft drinks to prolong shelf life.
• It is an odourless, crystalline powder made by combining benzoic acid and sodium hydroxide.
• Benzoic acid is a good preservative on its own, and combining it with sodium hydroxide helps it dissolve in products.
• Sodium benzoate does not occur naturally, but benzoic acid is found in many plants, including cinnamon, cloves, tomatoes, berries, plums, apples, and cranberries.

Additional Information