Free Biodiversity and Variety of Life MCQs with Answers

1951. The hair found in the inflorescence of Zea mays are the modification of

• A. Style
• B. Stigma
• C. Spathe
• D. Filaments

Explanation: (a): In maize style, it is very long. It comes out of the cob to expose stigma for wind pollination. These are collectively known as silk.

1952. Angiosperm, to which the largest flowers belong is:

• A. Total root parasite
• B. Partial root parasite
• C. Total stem parasite
• D. Partial stem parasite

Explanation: Rafflesia is a specialized total root parasite as the vegetative parts of its body are reduced the whole body is within the host root and the only structure that is visible outside, is the biggest flower. The diameter of the flower is one meter and its weight is about 10 kg. Its pollination is done by elephants. The flowers are fleshy white and they emit a smell, which resembles the smell of decaying meat.

1953. Hypanthodium is a specialized type of

• A. Fruit
• B. Inflorescence
• C. Thalamus
• D. Ovary

Explanation: (b): Inflorescence is the cluster of flowers or arrangement of flowers on the floral axis. Hypanthodium is the characteristic inflorescence of Ficus (Family Moraceae). Here a cup­shaped cavity with an apical opening or ostiole is formed by a fleshy receptacle, which is guarded by inwardly projecting hairs and bears flowers on the inner wall of the cavity, i.e., female ( + ) flowers at the base and male flowers above.

1954. Fruit of Mangifera indica is

• A. Berry
• B. Drupe
• C. Capsule
• D. Siliqua

Explanation: (b): Cypsella is a dry, one chambered, one seeded fruit developing from an inferior, bicarpellary ovary, e.g., sunflower, marigold, cosmos, etc. Caryopsis or grain is a small, dry one seeded fruit developing from superior monocarpellary ovary. Pericarp fused with the seed coat, e.g., rice, wheat, maize, etc. Cremocarp is a bilocular, two seeded fruit developing from an inferior bicarpellary ovary. It is characteristic fruit of umbelliferae, e.g.,Coriander, Cuminum, etc. Berry or bacca develops from mono or multicarpellary superior or inferior syncarpous ovary withaxile or parietal placentation, e.g., tomato, banana, brinjal, guava, grapes etc.

1955. Tegmen develops from

• A. Funiculus
• B. Chalaza
• C. Inner integument
• D. Outer integument

Explanation: (c: The outer protective covering of the seed is called seed coat which develops from integuments of ovules. The seeds developing from bitegmic ovules have two layers. The outer layer is called the testa and the inner layer or tegmen develops from inner integuments.

1956. The oil reserve of groundnut is present in

• A. Embryo
• B. Cotyledons
• C. Endosperm
• D. Underground tubers

Explanation: (b): In groundnut the food/oil reserve is present in cotyledons. It is a very important commercial crop of Leguminosae.

1957. Fruit of groundnut is

• A. legume
• B. Caryopsis
• C. Berry
• D. Nut

Explanation: (a): Fruit of groundnutis legume. It is developed from monocarpellary ovary but dehisces by both sutures from apex downward.

1958. The common bottle cork is a product of

• A. Dermatogen
• B. Phellogen
• C. Xylem
• D. Vascular cambium

Explanation: (b): Cork cambium or phellogen is a type of cambium arising within the outer layer of the stems of woody plants, usually as a complete ring surrounding the inner tissues. The cells of the cork cambium divide to produce an outer corky tissue (cork or phellem) and an inner secondary cortex (phelloderm). The common bottle cork produced from Quercus suber is a product of phellogen.

1959. In barley stem, vascular bundles are:

• A. Closed and scattered
• B. Open and in a ring
• C. Closed and radial
• D. Open and scattered

Explanation: Barley is a monocotyledonous plant. The vascular bundle of stem is conjoint,collateral,exarch and closed (because cambium is absent). It is also scattered throughout the ground tissue.As barley is monocot plant, the vascular bundles have no cambium and do not form secondary tissues. Hence, they are referred to as closed. Also, in monocot stems, the vascular bundles are scattered in the ground tissue, are many in number and vary in size.

1960. The aleurone layer in maize grain is specially rich in:

• A. Proteins
• B. Starch
• C. Lipids
• D. Auxins

Explanation: In monocotyledons the seeds are generally endospermous. The internal structure of grain can be studied in a longitudinal section. It shows two distinct regions upper large region, the endosperm and lower smaller region, the embryo. The endosperm is surrounded by a special one cell thick layer, called aleurone layer. Itis filled with aleurone grains which are proteinaceous in nature. Other components of this layer are phytin, carbohydrates and small amounts of phospholipids are also present.