Free Kingdom Plantae MCQs with Answers

91. The standard petal of a papilionaceous corolla is also called

• A. Vexillum
• B. Corona
• C. Carina
• D. None of these

Explanation: (a) : The posterior large bilobed petal of a papilionaceous corolla is called standard or vexillum. It overlaps the two smaller lateral petals known as wings or alae. Therefore, the correct answer is Vexillum. The vexillum is the large, upper petal of a papilionaceous corolla, and it is also called the standard petal. The corona is a ring of fused petals, and the carina is the two lowest petals of a papilionaceous corolla.

92. Tricarpellary, syncarpous gynoecium is found in flowers of

• A. Fabaceae
• B. Poaceae
• C. Liliaceae
• D. Solanaceae

Explanation: (c) : Liliaceae is a family of flowering plants that includes lilies, tulips, and onions.Members of Liliaceae possess tricarpellary, syncarpous gynoecium with superior ovary. The ovary is trilocular with two to many ovules in each loculus. Therefore, the correct answer is Liliaceae. Liliaceae flowers are the only ones that have a tricarpellary, syncarpous gynoecium.

93. Which of the following is not a stem modification?

• A. Tendrils of cucumber
• B. Flattened structures of Opuntia
• C. Pitcher of Nepenthes
• D. Thorns of citrus

Explanation: (c) : Pitcher of Nepenthes is a modification of leaf. The correct answer is Pitcher of Nepenthes.Tendrils of cucumber, flattened structures of Opuntia, and thorns of citrus are all stem modifications. Stem modifications are structures that have evolved from stems to perform specific functions. Tendrils of cucumber: Tendrils are thin, thread-like structures that help plants climb. They are modified from axillary buds, which are small buds that are located in the axils of leaves. Tendrils wrap around objects, such as branches or fences, to support the plant as it grows. Flattened structures of Opuntia: Opuntia is a genus of cacti that includes the prickly pear. The flattened structures of Opuntia are called phylloclades. Phylloclades are modified stems that have become flattened and fleshy. They perform photosynthesis, which is the process by which plants produce food from sunlight, water, and carbon dioxide. Phylloclades also store water, which helps the plants survive in desert environments. Thorns of citrus: Thorns are sharp, pointed structures that protect plants from herbivores. They are modified from axillary buds. Thorns deter animals from eating the plants, which can damage the plants and reduce their ability to reproduce. Pitcher of Nepenthes: Nepenthes is a genus of carnivorous plants. The pitchers of Nepenthes are modified leaves that trap and digest insects. The pitchers have a slippery surface and a pool of digestive fluid at the bottom. Insects are attracted to the pitchers by the sweet nectar that is produced by the plant. Once an insect falls into the pitcher, it cannot escape and is eventually digested by the plant.

94. The wheat grain has an embryo with one large, shield shaped cotyledon known as

• A. Scutellum
• B. Coleoptile
• C. Epiblast
• D. Coleorhiza

Explanation: The wheat grain has an embryo with one large, shield-shaped cotyledon known as the scutellum. The scutellum is a specialized cotyledon found in the embryos of grasses, including wheat. It is responsible for absorbing nutrients from the endosperm of the seed during germination and providing them to the developing plant.

95. Axile placentation is present in

• A. Pea
• B. Argemone
• C. Dianthus
• D. Lemon

Explanation: (d) :Axile placentation occurs in syncarpous pistils. Lemon is the only plant listed that has axile placentation. Pea has marginal placentation, which means that the ovules are borne on the margins of the carpels. Argemone has parietal placentation, which means that the ovules are borne on the inner walls of the ovary, but not on the central axis. Dianthus has free central placentation, which means that the ovules are borne on a central column that is not attached to the sides of the ovary. Lemon has axile placentation, which means that the ovules are borne on the central axis of the ovary.Therefore, the correct answer is lemon.

96. Roots play insignificant role in absorption of water in

• A. Pea
• B. Wheat
• C. Sunflower
• D. Pistia

Explanation: (d) : Pistia (water lettuce) is a floating aquatic plant. In aquatic plants, roots are generally poorly developed and do not take part in absorption of water. Water is absorbed by the general body surface in these plants. In summary, all four plants have roots that play a role in water absorption, but the importance of roots varies depending on the plant's habitat. Pea, wheat, and sunflower plants are terrestrial plants that rely on their roots for water absorption. Pistia is an aquatic plant that absorbs water through its leaves.

97. Perigynous flowers are found in

• A. Mustard
• B. Rose
• C. Guava
• D. Cucumber

Explanation: Mustard (Brassicaceae) has hypogynous flowers, meaning the ovary is superior and the other floral parts are attached below it. The sepals, petals, and stamens are attached to the receptacle, which is the expanded base of the flower that supports the floral organs. The ovary is typically four-lobed and contains numerous ovules. Rose (Rosa spp.) also has perigynous flowers. The hypanthium is typically more developed in roses than in China roses, and it is often fleshy and fragrant. The sepals, petals, and stamens are attached to the rim of the hypanthium. Guava (Psidium guajava) has epigynous flowers, meaning the ovary is completely inferior. The sepals, petals, and stamens are attached to the hypanthium, which surrounds and fuses with the ovary. Cucumber (Cucumis sativus) has epigynous flowers. The hypanthium is typically less developed in cucumbers than in guavas, and it is not fleshy or fragrant. The sepals, petals, and stamens are attached to the rim of the hypanthium. Therefore, the correct answer is Rose.

98. Keel is the characteristic feature of flower of

• A. Aloe
• B. Tomato
• C. Tulip
• D. Indigofera

Explanation: (d) : The flowers of Family Papilionaceae have butterfly shaped corolla (papilionaceous corolla). The correct answer is Indigofera. Indigofera is a genus of flowering plants in the legume family, Fabaceae. The flowers of Indigofera have a characteristic keel, which is a large, fused petal that forms the lower part of the flower. The keel is often brightly colored and attracts pollinators. Aloe is a genus of succulent plants in the family Xanthorrhoeaceae. The flowers of aloe are typically tubular or bell-shaped and do not have a keel. Tomato is a flowering plant in the nightshade family, Solanaceae. The flowers of tomato are also typically tubular or bell-shaped and do not have a keel. Tulip is a genus of spring-blooming perennial herbaceous bulbiferous plants in the lily family, Liliaceae. The flowers of tulips are typically cup-shaped or bell-shaped and do not have a keel.

99. Leaves become modified into spines in

• A. Onion
• B. Silk cotton
• C. Opuntia
• D. Pea

Explanation: (c) : In xerophytic plants, the leaves modify into sharp, pointed spines e.g. Aloe, Solanum surattense, Opuntia, Asparagus etc. This modification is either for protection of plant or to lessen transpiration, or for both. The correct answer is Opuntia. Opuntia is a genus of cacti that have modified their leaves into spines. This is an adaptation to help the plant conserve water and protect itself from herbivores. The spines are sharp and pointed, and they make it difficult for animals to eat the plant. The spines also help to shade the plant and reduce water loss through transpiration.

100. Placenta and pericarp are both edible portions in

• A. Apple
• B. Banana
• C. Tomato
• D. Potato

Explanation: (c) : A true fruit consists of a pericarp (fruit wall) formed from ovary wall and seeds formed from ovules. Pericarp is divisible into epicarp, mesocarp and endocarp. Tomato is a berry fruit derived from bicarpellary, syncarpous, bi­to tetralocular ovary with swollen placentae. Berry consists of a membranous skin represented by epicarp. Mesocarp is the middle fleshy part. Endocarp, septa and placentae are pulpy and edible. All parts of the fruit, except the small seeds, are edible.