Anatomy of Plants MCQ Quiz in मल्याळम - Objective Question with Answer for Anatomy of Plants - സൗജന്യ PDF ഡൗൺലോഡ് ചെയ്യുക

The correct answer is Statement I is false but Statement II is true

Explanation:

Statement I: Parenchyma is living but collenchyma is dead tissue

• Parenchyma cells are indeed living tissue and retain the ability to divide and contribute to the plant's growth.
• Collenchyma cells are also living cells. They provide structural support, particularly in regions of new growth, and are characterized by their thickened cell walls. Therefore, the statement that collenchyma is dead tissue is incorrect.

Statement II: Gymnosperms lack xylem vessels but the presence of xylem vessels is a characteristic of angiosperms

• This statement is correct.
• Gymnosperms typically have tracheids for water conduction but lack xylem vessels, which are more efficient conduits for water transport.
• Xylem vessels are characteristic of angiosperms (flowering plants), contributing to more advanced water transportation systems.

Key Points

• Cells of this tissue are living and show angular wall thickening. They also provide mechanical support, this tissue is collenchyma.
• Collenchyma is a simple permanent tissue.
• It allows the bending of various parts of a plant like tendrils and stems of climbers without breaking.
• This tissue is found in leaf stalks below the epidermis.
• There is very little intercellular space among the cells.

Additional Information

• Xylem-
  • ​It is a vascular tissue.
  • It transports water and minerals to the leaves that are absorbed by the roots.
  • Xylem consists of tracheids, vessels, xylem
    parenchyma, and xylem fibres.
• Sclerenchyma-
  • ​They are long and narrow as the walls are thickened
    due to lignin.
  • The cells of this tissue are dead.
  • This tissue is present in stems, around vascular bundles, in the veins of leaves, and in the hard covering of seeds and nuts.
• Epidermis-
  • ​The epidermis is the outermost layer of the primary plant body.
  • It is made up of elongated, compactly arranged cells, which form a continuous, single layer.

Hence, the correct option is (3) Collenchyma.

The correct answer is xerophytes.

Key Points

• Xerophytes are plants found in the desert area.
• They require the least amount of water. In deserts there is a scarcity of water thus the plants have to take their water from the underground water level.
• Their stomata are of sunken type (deep-seated) like cup – shape depression as it helps them to prevent the loss of water through transpiration.
• Examples of xerophytes are – Aloe vera, Pineapple, Cactus, etc.

• The stomata are minute pores that occur in the epidermis of the plants.
• Each stoma remains surrounded by two kidneys or bean-shaped epidermal cells the guard cells.
•  The stomata may occur on any part of a plant except the roots.
• The epidermal cells bordering the guard cells are called accessory cells or subsidiary cells.
• The number and types of stomata vary in different plant species based on their Habitat.

Additional Information

• Hydrophytes are plants that are either partially or fully submerged into water.
• Partially submerged hydrophytes like Lilly have stomata present on their upper leaf surface (lower pat is submerged in water).
• Fully submerged hydrophytes like water ferns do not have stomata, instead of stomata, the plant's surface cells are capable of absorbing water, nutrients, and dissolved gases in the water.
• Mesophytes have generally stomata present on the lower surface of the epidermis
• Examples are corn(maize), clover, cucurbit, etc
• Parasite: The organism that lives on or inside other living organisms, to derive their food are called parasites. Amarbel (Cuscuta) is a ''parasite''.

Concept:

• Epidermis is the layer of cells present on the outside of plant structures such as stem, root, leaf, flower, fruit and seed.
• Epidermis comprises pavement cells, guard cells and subsidiary cells.
• Functions - 
  • Provides a barrier against water loss, infection and mechanical injury.
  • Helps regulate gas exchange.
  • Regulates transpiration.
  • Increases water absorption, etc.

Important Points

• Hair-like projections that extend from the epidermis are called trichomes.

Trichomes - 

• ​Trichomes are referred to as leaf hair.
• These can be singular or multicellular.
• The shape of trichomes helps in identifying a plant species.
• Trichomes are controlled by trichome specificity genes.
• The chemicals produced by trichomes in their glandular tips protect the plant from being eaten by insects.
• Apart from this, trichomes also produce secondary chemicals that are used as useful products such as fragrances and flavors.
• Some trichomes also contain irritants that can cause rashes in humans.
• In insectivorous plants like Drosera, trichomes secrete exudate that helps in trapping the prey.​

So the correct answer is option 4 (Trichomes).

Key Points

• Epithelial tissue or epithelium is a type of animal tissue that is found covering the outer surface of the body or organs. It is also present as a lining of the various ducts and tubes inside the body.
• It has a free surface that faces either a body fluid or an outside environment.
• The cells of the epithelial tissue lie on a thin layer of supportive tissue membrane called the basement membrane.
• There is no intercellular space between the compactly placed cells of the epithelial tissue.
• Epithelial tissue does not have blood vessels. Hence it is non-vascular.
• The main function of epithelial tissue is to protect other tissues.
• It may perform different functions depending on its location. E.g. Absorption in the digestive system, Secretion in gland cells, etc.
• Epithelial tissue has great regeneration power.
• There are two main types of epithelial tissue depending on the number of layers - Simple epithelium and Compound (Stratified) epithelium.

1. Simple epithelium:

• It is made up of a single layer of cells.
• It functions as a lining for the body cavity, ducts and tubes in the body.
• Simple epithelium is further divided into the following types: 
  1. Squamous epithelium
  2. ​Cuboidal epithelium
  3. Columnar epithelium
  4. ​Ciliated epithelium
  5. Glandular epithelium​​

2. ​​​Compound epithelium:
   • ​It is made up of more than one layer of cells.
   • The main function of compound epithelium is to protect other cells.

Explanation:

• a - always ciliated
  • This option is incorrect with regard to epithelial tissue.
  • Not all types of epithelial tissues bear cilia.
  • Ciliated epithelium is a type of epithelial tissue that bears cilia.
• b - non-vascular
  • This option is correct with regard to epithelial tissue.
  • Epithelial tissues do not have blood vessels.
  • Hence it can be regarded as non-vascular.
• c - with lots of extracellular material​
  • This option is incorrect with regard to epithelial tissue.
  • Epithelial tissues have scanty extracellular material.
  • The extracellular matrix consists of mainly the thin membrane - basement membrane. 
• d -  tightly packed​
  • This option is correct with regard to epithelial tissue.
  • The cells of the epithelial tissue are compactly packed with no intercellular space.

So the correct answer is option 2 - (b) + (d).

The correct answer is thalamus

Explanation

Epicarp: This is the outermost layer of the pericarp (fruit wall), commonly known as the skin or peel of the fruit. For example, in apples and pears, the epicarp is the outer skin that you see and touch.
Mesocarp: The mesocarp is the middle layer of the pericarp, usually the fleshy and often the most substantial part of the fruit. In some fruits like peaches and mangoes, the mesocarp is the juicy, edible portion.
Endocarp: This is the innermost layer of the pericarp, which directly surrounds the seed(s). It can be hard or stony in some fruits like peaches and cherries (forming the pit), or it can be more membranous as in apples and pears.
Thalamus: In the case of apples and pears, the thalamus is the part of the flower that develops into the fruit. These fruits are known as pome fruits, where the edible part is derived from the enlarged and fleshy thalamus. The true fruit part (which includes the pericarp: epicarp, mesocarp, and endocarp) is actually the central core that surrounds the seeds.

Key Points

• Vessel and tracheids are one of the components of the xylem tissue.
• The xylem is a complex vascular tissue.
• Xylem transports water and minerals to the leaves that are absorbed by the roots.
• The other two components of xylem are xylem
  parenchyma and xylem fibres.
• Tracheids and vessels are tubular structures and have thick walls, and many are dead cells when mature.
• This allows them to transport water and minerals vertically.

Explanation:

• Gymnosperms lack xylem vessels, it is a significant character of angiosperms.
• Pine is a gymnosperm and does not contain xylem vessels.
• However, teak, mango, and palm belong to Angiosperm. So that, they have vessels.

Hence, the correct option is (3) Pine.

The correct answer is a type of epidermal tissue.

Key Points

• Stomatal guard cells are a type of epidermal tissue.
• The epidermal tissue system forms the outermost covering of the whole body plant.
• In the epidermal tissue system, the epidermis is the outermost layer of the main plant body.
• This layer is interrupted by stomata.
• The stomata are openings in the epidermis of most of the aerial parts of the plants, especially in the leaves.
• Each stomata is composed of two bean-shaped cells called guard cells, which enclose the stomatal pore.
• The stomatal guard cells are generally much smaller in size as compared to other epidermal cells.
• Stomatal guard cells help to regulate the rate of transpiration during photosynthesis by opening and closing the stomata. 

Key Points

• Casparian strips are located on the roots of the endodermis of vascular plants.
• It is a band of cell wall material deposited on the radial as well as tangential walls of the endodermis.
• The endodermis is the innermost layer of the cortex. It is made up of parenchymatous cells.

Explanation:

• Casparian strips are made of suberin.
• Suberin is a water-impermeable and waxy material.
• It is a lipophilic, hydrophobic polyester biopolymer.
• It blocks the passive flow of water and solutes into the stele of a plant.
• Suberin prevents water from entering the pericycle.
• Thus, Casparian strips help in producing root pressure.

Additional Information

• Chitin - is the N-acetylglucosamine polymer found in the cell wall of fungi and exoskeletons of Arthropods.
• Cellulose - is a polysaccharide and a structural component of the primary cell wall of plants.
• Pectin - is a heteropolysaccharide present in the primary cell wall and middle lamella of plants.

Hence, the correct option is (4) Suberin.

The correct answer is 1 → C, 2 → A, 3 → B, 4 → D

Explanation:

• Hypodermis: The hypodermis is the layer beneath the epidermis, often composed of collenchyma or sclerenchyma cells. It provides mechanical strength to the plant, helping it withstand various stresses.
• Endodermis: The endodermis is the innermost layer of the cortex surrounding the vascular cylinder. It is characterized by the presence of Casparian strips and often accumulates starch, which is why it's also called the starch sheath.
• Pericycle: The pericycle is a layer of cells located just inside the endodermis and surrounding the vascular bundles. It plays a key role in the formation of lateral roots and contributes to the secondary growth in dicot roots.
• Cortical layers below hypodermis consist of rounded thin walled parenchymatous cells with conspicuous intercellular spaces.