Describe the morphological characteristics, Biology

Assignment Help:

Q. Describe the Morphological Characteristics?

One of the first steps in the identification of bacteria in food is microscopic examination to ascertain the shape, size, aggregation, structure and staining reactions of the bacteria present. The following characteristics may be of special significance:

Encapsulation: The presence of capsules or slime may account for sliminess or ropiness of a food. Most capsules are polysaccharides of dextrin; dextran or levan and they serve as a source of reserve nutrients and increase the resistance of bacteria under adverse conditions.

Formation of Endospores: Bacteria of genera Bacillus, Clostridium, Sporosarcina etc have the ability to form endospores. Endospores are formed at an intracellular site and are resistant to heat, ultraviolet light and desiccation. Lysis of the vegetative cell releases the free endospore, which may remain dormant with no detectable metabolism for years. Sporulation usually appears in the late logarithmic phase of growth, possibly because of nutrient depletion or product accumulation. The acquisition of heat resistance is closely related to the formation of dipicolinic acid and the Ca2+ uptake. Germination is favoured by conditions that are favourable for growth.

Formation of Cell Aggregates: It is characteristic of some bacteria to form long chains or of others to clump under certain conditions. It is more difficult to kill all bacteria in intertwined chains or sizable clumps than to destroy separate cells.


Related Discussions:- Describe the morphological characteristics

What is passive transport , The passive transport of molecules across a me...

The passive transport of molecules across a membrane does not require an input of metabolic energy. Rate of the diffusion or transport is proportional to the concentration gradient

Proteins, assignment on the topic proteins

assignment on the topic proteins

Aids associated and adolescent crisis emergencies, Other Psychiatric Emerge...

Other Psychiatric Emergencies:   1) Psychotropic Drug Withdrawal Abrupt cessation of antipsychotic, benzodiazepines result in symptoms of withdrawal including abdominal pain, i

Digestive system, Digestive system is one of eleven major body organ syste...

Digestive system is one of eleven major body organ systems in animals; it converts food from the external environment into the nutrient molecules which can be used and stored by t

Explain what is pulse, Explain what is pulse ? Examination of periphera...

Explain what is pulse ? Examination of peripheral pulses as a very important step in cardiovascular examination. A normal pulse has upstroke (anacrotic limb) followed by a down

Explain ground system, G round system:  Plant tissue system, composed com...

G round system:  Plant tissue system, composed commonly of parenchyma cells with some collenchyma and sclerenchyma cells, that occupies the space between the epidermis and the va

Metabolic alterations and nutritional problems - cancer, Metabolic Alterati...

Metabolic Alterations and the Resultant Nutritional Problems/ Clinical Manifestations Associated With Cancer? Several research studies have shown that malignant growth (cancer)

Explain the term - neurochemical manipulations, Explain the term - Neuroche...

Explain the term - Neurochemical Manipulations Neurochemical and immunological methods have been used to identify groups of neurons in the central nervous system that use speci

Explain the uses of isP in cereal products, Explain the Uses of ISO in Cere...

Explain the Uses of ISO in Cereal products  Cereal products  ISP is sometimes used instead of, or in mixture with isolates and soy flour, in the formulation of milk replac

Main opportunistic diseases that can affect aids patients, Q. What are the ...

Q. What are the main opportunistic diseases that can affect AIDS patients? Among the opportunistic diseases that affect HIV contaminated people during the AIDS stage some are:

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd