JNTU B.Pharmacy I Year REMEDIAL BIOLOGY Previous Question Paper (July-2021 - R17)

The morphology of flowering plants (Angiosperms) refers to the study of their external form and structure. A typical flowering plant is divided into two main systems: the root system and the shoot system.

1. The Root System: The root is the underground part of the plant. It develops from the radicle of the embryo. There are three main types: tap root system (e.g., mustard), fibrous root system (e.g., wheat), and adventitious roots (e.g., banyan tree). Roots function in anchorage, absorption of water and minerals, and storage of food.

2. The Shoot System: This is the aerial part of the plant, developing from the plumule. It consists of the stem, leaves, flowers, and fruits.

3. Stem: The stem is the central axis that bears branches, leaves, flowers, and fruits. It conducts water and minerals from roots to leaves and transports food from leaves to other parts.

4. Leaf: The leaf is a lateral, flattened structure borne on the stem at the node. It is the primary organ for photosynthesis. It consists of the leaf base, petiole, and lamina. Leaves exhibit different types of venation (reticulate or parallel) and phyllotaxy (arrangement of leaves on the stem).

5. Inflorescence: This is the arrangement of flowers on the floral axis. The two main types are racemose (main axis continues to grow) and cymose (main axis terminates in a flower).

6. Flower: The flower is the reproductive unit of an angiosperm. It typically consists of four whorls: calyx (sepals), corolla (petals), androecium (stamens), and gynoecium (carpels). The flower is essential for sexual reproduction.

7. Fruit and Seed: After fertilization, the ovary matures into a fruit, and the ovules develop into seeds. The fruit protects the seeds and aids in their dispersal, while the seed contains the embryo and food reserves necessary for the development of a new plant.

Kingdom Monera consists of unicellular, prokaryotic organisms, primarily bacteria and cyanobacteria. Their key features include:

• Cell Structure: They lack a well-defined nucleus and membrane-bound organelles like mitochondria or chloroplasts. The genetic material exists as a circular double-stranded DNA molecule called the nucleoid.
• Cell Wall: Most possess a rigid cell wall composed of peptidoglycan (murein).
• Nutrition: They exhibit diverse modes of nutrition, including autotrophic (photosynthetic or chemosynthetic) and heterotrophic (saprophytic or parasitic) types.
• Reproduction: Primarily reproduce asexually through binary fission or budding. Genetic recombination may occur via conjugation, transformation, or transduction.
• Locomotion: Many species are motile, utilizing flagella composed of the protein flagellin.

Kingdom Plantae comprises multicellular, eukaryotic, photosynthetic organisms. Their key features include:

• Cellular Organization: Cells are eukaryotic with a distinct nucleus and membrane-bound organelles. They possess a rigid cell wall made of cellulose.
• Photosynthesis: They contain chlorophyll pigments within chloroplasts, enabling autotrophic nutrition by converting solar energy into chemical energy.
• Life Cycle: They exhibit 'alternation of generations', where a multicellular haploid gametophyte phase alternates with a multicellular diploid sporophyte phase.
• Growth: Growth is generally indeterminate and localized in meristematic regions.
• Classification: The kingdom is broadly categorized into non-vascular plants (Thallophyta, Bryophyta) and vascular plants (Pteridophyta, Gymnosperms, and Angiosperms).