Optionals IAS Mains Botany: Questions 202 - 211 of 511

Sleginella

• The section of strobilus axis with which is attached micro and megasporophyll.
• The strobilus shows the presence of both microsporangia and Megasporangia. In some species one side of the strobilus bears microsporangia and other side bears Megasporangia.
• Usually the Megasporangia are located in the basal portion and the microsporangia in the …

Development of Sporophyte Found in Bryophyte

Ribosome Synthesis

Synthesis of ribosome various component is under genetic control that are Transcripted by genes.

Synthesis of 70s Ribosome

• The ribosomal genes are in single operon which is transcribed as a unit, to synthesis molecule of RNA containing 16s, 23s, 5s rRNA sequence.
• rRNA if greatly stabilized and protected by ribosomal proteins and thus…

Accessory Chromosome

• B chromosomes are a heterogeneous class of chromosome found in nucleus and called accessory chromosome.
• These accessory chromosomes are not essential chromosome as they are not essential for life as they are not even present in all individuals.
• B chromosome are different from maker chromosome or additional copies of normal chromos…

Powdery Mildew Diseases in Plants

• mildews is disease in with the pathogen grows mostly on the surface of the host and appears in the form of white, grey, brown leaves, youngest and fruits.
• When the spores are in the form of powdery layer on the host surface, they are called as powdery mildews.

Causal Organism

• Disease is caused by the member of Erysipha…

Palmella Stage

• A Colonial aggregate of immobile non-flagellated individuals occurring regularly in the life cycle.
• Unlike coenobial forms, in a palmelloid colony the number of cells, their shape and size is not definite.
• The cells remain irregularly aggregated within a common mucilaginous matrix.
• They are independent and function as individuals.
• In some…

Fermentation

• Fermentation is the incomplete oxidation of glucose is achieved under anaerobic conditions by sets of reactions where pyruvic acid is converted to CO₂ and ethanol.
• The enzymes, pyruvic acid decarboxylase and alcohol dehydrogenase catalyse these reaction. Some bacteria also form lactic acid and pyruvic acid. Also in some animal cell like …

Importance of VAM

• VAM is vesicular Arbuscular Mycorrhizal is a fungus which has the ability to dissolve the phosphates that is found abundantly in soil.
• And hence VAM is work in favour of plants to absorbed nutrients from soil.
• They are type of Mycorrhiza (symbiotic combination of fungus and plants) .
• These fungus depend on plants for starch and in ret…

Protoplast Fusion

• Protoplast fusion is a type of genetic modification in the plants by which genome of two distinct species of plants are fused together to form new hybrid. That has characteristics of both the species.
• Protoplast fusion can be obtain either by spontaneous fusion method or induced fusion methods.

Spontaneous Fusion Method

• During isolati…