Researchers studying the rigidity and flexibility of the cell envelope used chemotaxis to measure the ability of microbes to squeeze through tight spaces. e. coli, a gram-negative bacterium, was able to traverse narrower channels than b. subtilis, a gram-positive microbe, even though both cells are the same size when grown without restriction. e. coli has the more flexible cell envelope becausea. lipopolysaccharide has no charge.
b. it has fewer flagella.
c. it has only a single membrane.
d. there is less structural carbohydrate.
e. there are fewer protein receptors.
D. there is less structural carbohydrate.
Most bacterial cells have a cell wall located outside the plasma membrane, formed by peptideoglycan or murein, which provides protection and shape to the cell. In addition to the wall, some bacteria have a polysaccharide capsule that surrounds this structure, this capsule is a carbohydrate envelope that can allow more or less flexibility to the bacterial cell. The more structural carbohydrates the polysaccharide capsule has the less flexible the bacteria will be. Thus, we can say that if E. coli has the most flexible cell envelope, compared to the envelope of other bacteria, it is because there is less structural carbohydrate in the E. coli envelope.
Explanation:The microorganisms cell envelope is a complex multilayered structure that serves to shield these life forms from their unpredictable and regularly antagonistic condition. The cell envelopes of most microscopic organisms can be categorized as one of two significant gatherings. Gram-negative microorganisms such as E.Coli are encompassed by a meager peptidoglycan cell divider, which itself is encompassed by an external layer containing lipopolysaccharide. Gram-positive microscopic organisms do not have an external film however are encompassed by layers of peptidoglycan commonly thicker than is found in the Gram-negatives.
b,bacteria convert nitrates
into nitrogen gas.
d,plants and animals take in
and use nitrogen compounds.
e,bacteria break down waste
products and return nitrogen
to the soil.
a,bacteria convert atmospheric
nitrogen to ammonia.
c,bacteria convert ammonia
to nitrites and nitrates.