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

Explain the evolution of the vascular plant body, Explain the Evolution of ...

Explain the Evolution of the Vascular Plant Body? Vascular Plant anatomy reflects adaptation to life on land. In an aquatic environment, the photosynthetic surfaces are support

Monosaccharide derivatives, MONOSACCHARID E DERIVATIVES They are modif...

MONOSACCHARID E DERIVATIVES They are modified monosaccharides. G L YCOSIDES They are compounds formed by condensation reaction between a sugar and hydroxyl group

Write the meaning of insulin, Q. Write the meaning of insulin? Insulin ...

Q. Write the meaning of insulin? Insulin is a hormone. And like many hormones, insulin is a protein. Insulin is secreted by groups of cells within the pancreas called islet cel

Define comprehensive dietary management regime of patient, Define Comprehen...

Define Comprehensive Dietary Management Regime of Patient? A comprehensive dietary management regime of the patient should be based on the patient profile as gathered pre and p

Explain the escherichia - characteristics of bacteria, Explain the Escheric...

Explain the Escherichia - Characteristics of Bacteria? It belongs to order Enterobacteriales. It is the best-studied organism present in the colon of humans and other warm-bloo

Growth and development of multi cellular organisms, Growth and development ...

Growth and development of multi cellular organisms The normal growth and development in all multicellular organisms occur in a programmed manner. The new born babies have

Determine the number of cell clusters, A cellular system has a total of 500...

A cellular system has a total of 500 duplex voice channels. The service area is divided into 150 cells. Suggest a three different cluster size (N) values. In each case, determine

Lan in hospitals, LAN LAN stands for Local Area Network. This kind of ...

LAN LAN stands for Local Area Network. This kind of network consists of a set of interconnected computers that are not geographically spread out over a large area. For exa

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