E-Lecture - Important Point
- Algae are defined as a group of predominantly aquatic, photosynthetic, and nucleus-bearing organisms that lack the true roots, stems, leaves, and specialized multicellular reproductive structures of plants. It is an important group of Thallophyta, the primitive and simplest division of the plant kingdom.
- In classification of algae various features that differentiate various types of algae are: organelle structure, flagellar apparatus, and cell division process.
- Cyanophyceae: simple unicellular, colonial or multicellular bodies, Principal pigments are chlorophyll-a, β-carotene, xanthophyll and phycobilins, c-phycoerythrin and cphycocyanin,
- Sexual reproduction in Spirogyra is isogamous, i.e. male and female gametes of similar size fuse together in the sexual reproduction. Sexual reproduction is by conjugation. Spirogyra asexually reproduces by fragmentation. Spirogyra breaks into two or more segments and each segment form new organism. Algae are used in medicine, as food and in industries.
- Moss plant is a gametophyte. It consists of an unbranched or branched shoot with spirally arranged small green leaves. At the base of shoot, numerous multicellular rhizoids are developed. These rhizoids functions as roots. Gametophytic generation reproduces sexually by gametes and is haploid. Sporophytic generation reproduces asexually by meiospores and is diploid. These two generations follow each other in alternate sequence. This phenomenon is termed alternation of generations.
- Ferns are flowerless green plants. They are usually easy to recognize by the feather like shape of their leaves, which are called fronds. Ferns reproduce by spores rather than by seeds.
- The fern life cycle requires two generations of plants to complete itself. This is called alternation of generations.
- Fungi are Eukaryotic organisms, non-vascular organisms, no embryonic stage for fungi and are typically non-motile. Fungi cannot prepare their food. They live as heterotrophs i.e., as parasites and saprophytes. Asexual reproduction, sometimes called somatic or vegetative, does not involve the union of nuclei or sex cells. Sexual reproduction is characterized by the union of two nuclei. Typically, fungi reproduce both asexually and sexually.
- Photosynthesis is the process through which green plants and other living things convert the energy of light into chemical. Leaves are adapted for photosynthesis by having a large surface area and contain openings, called stomata to allow carbon dioxide into the leaf and oxygen out.
- The overall process of photosynthesis is made up of two stages, commonly referred to as the light reaction and the dark reaction. The light reaction proceeds in the light. The energy rich light reaction products, ATP and NADPH. It takes place in the thylakoid membranes of the chloroplast and includes photosynthetic pigments arranged into two light-harvesting complexes within photo system I and photo system II.
- Dark reaction is a light-independent process in which sugar molecules are formed from the carbon dioxide and water molecules. The dark reaction occurs in the stroma of the chloroplast, where they utilize the products of the light reaction.
- Macronutrients are the main nutrients needed for plant growth and development. The macronutrients include nitrogen, phosphorus, and potassium.
- A micronutrient is the small number of chemicals that is present in soil, water, or air that helps the plants to grow faster. They help to increase the strength of the roots and leaves of the plants
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