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

Gonads and ovary - reproduction, Normal 0 false false false...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Diaphragmatic hernia, Diaphragmatic Hernia: In this condition there  i...

Diaphragmatic Hernia: In this condition there  is a slight herniation ofabdominal organs  (stomach intestine and liver) or extreme protrusion of abdominal contents into the th

Developmental biology, do you have college level developmental biologists a...

do you have college level developmental biologists available

Explain the flavour binding, Explain the Flavour Binding? Some protein ...

Explain the Flavour Binding? Some protein preparations, although acceptable from a functional and nutritional stand point, necessitate a deodorizing step to remove the bound of

Chromophore - development of plant, Chromophore - Development of plant ...

Chromophore - Development of plant The chromophore is a tetrapyrrole molecule like chlorophyll, but unlike chlorophyll it is an open tetrapyrrole and contains no metal ion. It

Determine indicators used in monitoring and surveillance, Determine Indicat...

Determine Indicators used in monitoring and surveillance? Various simple indicators may be used such as: 1) Weight-for-height 2) Body mass index (weight in kg/square of h

O-linked oligosaccharides , Most proteins made by ribosomes on the RER (rou...

Most proteins made by ribosomes on the RER (rough endoplasmic reticulum) are glycoproteins, which is they hold short chains of carbohydrates (oligosaccharides) covalently related t

Characters of vitamins, Characters of vitamins: Vitamins are organic...

Characters of vitamins: Vitamins are organic substances. They are micronutrients and are required in small quantities. They are not synthesised in the body and therefo

Which are the cell organelles that participate in cell, Q. Which are the ce...

Q. Which are the cell organelles that participate in cell division and in the formation of cillia and flagella of some eukaryotic cells? The organelles that participate in the

Assignment of botany, habitat, habit, cell wall chemistry, reason why cell ...

habitat, habit, cell wall chemistry, reason why cell wall like this of Archaebacteria , eubacteria,fungi,algae,bryophytes ,pteridophyes, gymnosperms , angiosperms..

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