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What is Respiration?

Q. What is Respiration? Definition : Respiration is the process by which chemical energy stored in the food is released in the form of ATP along with carbon dioxide and water. Whole the process completed inside the cell. It is also known as "cellular respiration". OR Oxidation of food with the help of inhaled oxygen and released energy is called Respiration , it always occurs at cellular level (inside the cell). Respiration completed in two step: i. Breathing (External Respiration) : Inhale of air and exhale of air is called Breathing. Breathing is not respiration, it is part of respiration. Without breathing respiration cannot be done. ii. Metabolism (internal Respiration) Cellular Respiration : It is the process which involves exchange of oxygen and carbon dioxide between the organisms and the environment.

Vegetative Reproduction by Stem

Vegetative Reproduction by Stem a. By Rhizome: These are Stem-like structures that’s grows horizontally across the ground and from which new roots and shoots may arise. They serve as protein and starch storage units serving as a nutrient source for newly developed plants. b. By Stems : In this process, new plants arise from the nodes. This is where buds are formed, which grow into new plants. Stems that grow horizontally on the ground are called runners . As these runners grow, bud formation at the nodes, which later develop the roots and shoots, resulting in the formation of new plant. E.g . Cyanadon , Mint etc. In the plant’s potatoes, stem tubers are found. This part is the swollen apical part containing many nodes or eyes. Every eye has buds. New plants originate from these buds.

Vegetative Reproduction by Roots

Natural Vegetative Propagation Natural vegetative propagation occurs when an axillary bud grows into a lateral shoot and develops its own roots (also known as adventitious roots). Plant structures allowing natural vegetative propagation include bulbs, rhizomes , stolons and tubers . Natural Reproduction done by following methods: a. By Roots : In this process, new plants grow out of the modified roots called tubers . Some plant roots also develop adventitious buds. These buds grow and form new plants/sprouts under the right conditions. These sprouts can be separated from the parent plant and when planted in other areas, new plants are formed. E.g . Sweet potato, Dahlia etc.

Vegetative Reproduction, Vegetative Propagation or Vegetative Multiplication

Vegetative Reproduction Ø Vegetative reproduction (also known as Vegetative Propagation, vegetative multiplication or cloning ). Ø It is a form of asexual reproduction, occurring in plants in which a new plant grows and form a fragment of the parent plant or a specialized reproductive structure. Ø Vegetative propagation is following two types on the basis of growing process: 1. Natural Vegetative Propagation 2. Artificial Vegetative Propagation

Reproduction by Zoospores

Reproduction by Zoospores o Members of Kingdom Fungi & algae reproduce through special reproductive structures called zoospores in aquatic medium. o These are flagellated, motile, naked protoplasmic bodies. o Zoospores are produced in Zoosporangium . o Zoospores are may be biflagellate (Chlamydomonas and Ectocarpus), Quadriflagellate (Ulothrix) or Multiflagellate (Oedogonium). o Multinucleated Zoospores are known as Synzoospores.

Reproduction By Conidia

Reproduction by Conidia: o These are non-motile spores produced endogenously by constriction at the tips of special hyphal branches known as conidiophores . o Asexual reproduction in ascomycetes (the phylum Ascomycota ) is the formation of conidia, which are borne on specialized stalks called conidiophores . o The morphology of these specialized conidiophores is often distinctive between species and, before the development of molecular techniques at the end of the 20 th century, was widely used for identification of (e.g. Metarhizium ) species.