Plant Morphology MCQ Quiz - Objective Question with Answer for Plant Morphology - Download Free PDF

The correct answer is Potato.

Key Points

• Potato is a modified stem.
  • Potato, ginger, and yam are modified stems because the stems are modified to perform the function of storage of food, support and protection.

Important Points

• Root vegetables include commodities, such as carrot, radish, horseradish, sweet potato, turnip, and beetroot.

The correct answer is Cytokinin.

Key Points

• Cytokinins are a group of plant hormones that promote cell division and growth in plant roots and shoots.
• They are known to delay the aging of plant tissues by inhibiting protein degradation and promoting protein synthesis and mobilization of nutrients.
• Cytokinins are synthesized in the roots and transported to other parts of the plant, including fruits and seeds, where they are present in high concentrations.
• In fruits and seeds, cytokinins play a crucial role in cell differentiation and development, as well as in the delay of senescence.
• They work synergistically with other hormones like auxins to regulate various growth processes and morphogenesis in plants.

Additional Information

• Auxin
  • Auxins are another group of plant hormones that primarily regulate cell elongation, especially in the stem and root tips.
  • They are involved in various growth processes including phototropism, gravitropism, and the formation of lateral and adventitious roots.
• Gibberellin
  • Gibberellins are plant hormones that promote stem elongation, seed germination, and flowering.They help in breaking seed dormancy and are involved in the regulation of various developmental processes.
• Abscisic Acid (ABA)
  • Abscisic acid is a plant hormone that primarily functions in stress responses, such as closing stomata during water stress.
  • It also plays a role in seed dormancy and inhibition of growth, helping plants to survive adverse conditions.

The Correct answer is Leaf.

Key Points

• The leaf is the primary organ of the plant involved in the process of transpiration.
• Transpiration is the process by which plants release excess water vapor into the atmosphere through small openings called stomata.
• Stomata are tiny pores located on the surface of leaves, primarily on the underside, which facilitate gas exchange and water vapor release.
• This process helps maintain the plant's water balance, regulates temperature, and aids in the uptake of minerals and water from the roots.
• The leaf structure includes epidermal layers, which protect the inner tissues, and a waxy cuticle that minimizes water loss.
• Transpiration also creates a transpirational pull, which assists in the upward movement of water and nutrients through the xylem.
• Leaves are uniquely adapted for this function due to their large surface area and the presence of chlorophyll for photosynthesis, which works in conjunction with transpiration.

Additional Information

• Root
  • The root system is primarily responsible for the absorption of water and nutrients from the soil.
  • Although roots play a crucial role in the plant's water uptake, they are not directly involved in the process of transpiration.
  • Roots also anchor the plant and store food reserves in some species.
• Stem
  • The stem serves as the main support structure for the plant and facilitates the transport of water, nutrients, and food between roots and leaves through the xylem and phloem.
  • While the stem helps in water movement, it does not directly carry out transpiration.
• Flower
  • The flower is primarily involved in the process of reproduction in plants.
  • It does not play a role in water regulation or transpiration.

The Correct answer is Option 1.

Key Points

• The Root performs the function of nutrient absorption. Roots absorb water and essential minerals from the soil, which are then transported to other parts of the plant.
• The Leaf is responsible for food synthesis through the process of photosynthesis. Leaves contain chlorophyll, which captures sunlight to produce food for the plant.
• The Stem facilitates the transport of water and nutrients between the roots and the leaves. It also provides structural support for the plant.
• The Flower plays a key role in reproduction. Flowers attract pollinators, enabling fertilization and the formation of seeds.
• The Fruit contains seeds, which help in the propagation of the plant species. Fruits protect seeds and aid in their dispersal.

Additional Information

• Root
  • The root system is essential for anchoring the plant in the soil.
  • Roots also store food in certain plants such as carrots, radishes, and beets.
  • They form a symbiotic relationship with certain fungi for enhanced nutrient absorption, known as mycorrhiza.
• Leaf
  • Leaves are the main site of photosynthesis, using sunlight, carbon dioxide, and water to produce glucose and oxygen.
  • Leaves also facilitate gas exchange through stomata, tiny openings on their surface.
• Stem
  • Besides the transport function, stems can store food and water in certain plants, such as sugarcane and cactus.
  • In some plants, stems are modified into structures like tendrils or thorns for specific functions.
• Flower
  • Flowers are the reproductive organs of angiosperms.
  • They produce seeds after fertilization, ensuring the continuation of the species.
• Fruit
  • Fruits come in various forms, such as dry fruits (e.g., nuts) and fleshy fruits (e.g., apples).
  • They aid in seed dispersal through mechanisms like wind, water, or animals.

The Correct answer is Statements I and II are correct.

Key Points

• Monocot plants typically have leaves with parallel venation, meaning the veins run parallel to each other throughout the length of the leaf.
• Monocot plants are characterized by having a fibrous root system, which consists of a network of roots of approximately the same size.
• Dicot plants have leaves with reticulate venation, meaning the veins form a net-like structure.
• Dicot plants possess a taproot system, where the main root grows deep into the soil and smaller lateral roots branch out from it.
• The statement regarding monocot plants being smaller in size than dicot plants (Statement III) is incorrect as there is no general rule about the size of monocots versus dicots. Monocots can include both small plants like grasses and large plants like palm trees.

Additional Information

• Monocot Plants
  • Examples of monocot plants include grasses, wheat, rice, maize, sugarcane, and bamboo.
  • Monocots typically have flower parts in multiples of three.
  • Monocot seeds contain a single cotyledon (seed leaf).
• Dicot Plants
  • Examples of dicot plants include rose, mango, beans, sunflower, and apple trees.
  • Dicots generally have flower parts in multiples of four or five.
  • Dicot seeds contain two cotyledons (seed leaves).
• Root Systems
  • Fibrous roots (in monocots) are highly efficient for quick absorption of nutrients and water, making them ideal for crops like wheat and rice.
  • Taproots (in dicots) allow plants to anchor deeply into the soil and access water from deeper layers, making them suitable for large trees like mango and neem.

The correct answer is Potato.

Key Points

• Potato is a modified stem.
  • Potato, ginger, and yam are modified stems because the stems are modified to perform the function of storage of food, support and protection.

Important Points

• Root vegetables include commodities, such as carrot, radish, horseradish, sweet potato, turnip, and beetroot.

The correct answer is Papaya.

• Papaya flowers are Unisexual Flowers.

Key Points

• Flowers that contain either only pistil (Female reproductive organs) or stamen (male reproductive organ) are called Unisexual flowers.
• Corn, papaya, Cucumber are some common examples.
•  A flower which contains both pistils (Female reproductive organs) and stamen (male reproductive organs) are called bisexual flowers.
• Sunflower, Mustard, Hibiscus are some common examples.

The correct answer is Petiole.

Key Points

• Petiole is like a stem that attaches the leaf blade to the stem.
  • Long thin flexible petioles allow leaf blades to flutter in wind, thereby cooling the leaf and bringing fresh air to leaf surface.

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Additional Information

• Pistil: The pistil is the innermost part of the flower. It is the female part of the flower.
• Stamen: The stamen is the male part of the flower.
• Petals: The petal is the coloured part of the flower that gives it a unique shape.
• Sepals: These are leaf-like structures attached to the outside of the flower. They're very similar to petals.
• The schematic diagram of the flower is as follows:

The correct answer is a female reproductive part.

Key Points

• Pistil is the female reproductive part of a flower with a stigma at its top.
• Pistil is the ovule producing part of a flower.
• The function of a pistil is to receive pollen and produce seeds.
• The ovary often supports a long style, topped by a stigma.
• The mature ovary is a fruit, and the mature ovule is a seed. 
• Pollens are produced by the male part of a flower called the stamen.
• A flower is actually made of specialized stems and leaves.

The correct answer is Angiosperm.

Key Points

• Angiosperms are also known as Angiospermae or Magnoliophyta.
  • They are flowering and seed-producing plants.
  • It consists of 64 orders, 416 families, approximately 13,000 known genera, and 3,00,000 known species.
  • Their seeds develop in the ovaries of flowers and are surrounded by a protective fruit.
  • Examples of angiosperms are fruits, vegetables, grains, and flowers.
  • Angiosperms are classified as Monocotyledons (monocots) and Dicotyledons (dicots) where monocots are flowering plants whose seeds contain only one embryonic leaf or cotyledon and dicots are flowering plants whose seeds contain two embryonic leaves or cotyledons.

Important Points

• Naked embryos are formed after fertilization and are not formed inside the seed.
• These are also known as spores.
• These embryos are the characteristic feature of Bryophytes and Pteridophytes.
• The reproductive organs bearing spores are also called sori.
• They also occur in various species of marine organisms like algae.

Additional Information

• Thallophyta
  • The plant body is not differentiated from roots, stems, and leaves.
  • They are commonly called algae.
• Bryophyta
  • These are small terrestrial plants.
  • They show differentiation in the body design, with stem, leaf-like structures, and root-like structures.
• Pteridophyta
  • ​Plants from this group have well-developed roots, stems and leaves and separate tissues for the conduction of food and water. But, they do not bear flowers and fruits.
  • They reproduce with the help of spores formed along the back or posterior surface of their leaves.
  • Examples- ferns like Nephrolepis, Marsilea, Pteris, Adiantum, Equisetum, Selaginella, Lycopodium, etc.

The correct answer is Pitcher plant.

Key Points

Pitcher plant:

• ​Pitcher plants (or pitfall traps) are carnivorous plants whose prey-trapping mechanism features a deep cavity filled with liquid known as a pitfall trap.
• Foraging, flying, or crawling insects such as flies are attracted to the cavity formed by the cupped leaf, often by visual lures such as anthocyanin pigments, and nectar bribes.
• The sides of the pitcher are slippery and may be grooved in such a way so as to ensure that the insects cannot climb out.
• Through a mechanism of digestion, the prey is converted into a solution of amino acids, peptides, phosphates, ammonium, and urea, from which the plant obtains its mineral nutrition (particularly nitrogen and phosphorus).
• Carnivorous plants occur in locations where the soil is too poor in minerals and/or too acidic for most plants to be able to grow.

The correct answer is roots.

Key Points

• Pneumatophores are specialized root structures that grow out from the water surface and help hydrophytic plants, such as many mangrove species, get the aeration they need for root respiration.
• Pneumatophores are specialized roots that sprout vertically out of the water or mud to reach the air and get oxygen for the root systems of marshy or tidal trees.
• Pneumatophores include mangrove knees and bald cypress. It is also known as the air root.
• These unique aerial roots allow plants to breathe air in wet environments. The roots can grow up from the stem or down from traditional roots.
• If they emerge from the earth, some botanists define them as aerating roots rather than aerial roots.

Explanation:

• Different parts of plants like roots, shoots, leaves, flowers, fruits, etc perform the function of storage of food 
• The fleshy leaves of onion are its consumable part.
• As a whole, the onion is a bulb, which is a short modified form of a stem that is surrounded by these fleshy leaves that store food for the onion shoots.

Important Points

• The stored food in onion leaves is Sugar.

Mistake Points​Food is stored in the leaves. Onion as a whole is a modified stem

Additional Information  

• In plants like carrot, reddish, beetroot, sweet potato, turnip, etc. roots perform the function of food storage.
• Some plants store their food in the form of fruit. Ex- apple, guava, grapes mango, etc.
• Plants like potato, ginger, garlic, sugarcane, etc. store their food in stems.​

The correct answer is option 4 i.e Stomata.

Key Points

• Stomata is a pore found in the epidermis of leaves, stems, and other parts of a plant.
  • Stomata help for the gas exchange.
  • The stomata is bordered by a pair of parenchyma cells called guard cells.
  • Guard cells are responsible for regulating the size of the stomatal opening.
  • Atmospheric air enters the plant through stomata by gaseous diffusion.
  • The lengths of stomata is ranging from 10 to 80 µm and width ranging from a few to 50 µm.
• Cilia are small hair-like protuberances on the outside of eukaryotic cells.

The correct answer is Root hairs.

Key Points

Fig: The regions of the root-tip