Search results
Results from the WOW.Com Content Network
The peptidoglycan layer is substantially thicker in gram-positive bacteria (20 to 80 nanometers) than in gram-negative bacteria (7 to 8 nanometers). [4] Depending on pH growth conditions, the peptidoglycan forms around 40 to 90% of the cell wall 's dry weight of gram-positive bacteria but only around 10% of gram-negative strains.
All living cells contain both DNA and RNA (except some cells such as mature red blood cells), while viruses contain either DNA or RNA, but usually not both. [15] The basic component of biological nucleic acids is the nucleotide, each of which contains a pentose sugar (ribose or deoxyribose), a phosphate group, and a nucleobase. [16]
Many carbohydrates contain modified monosaccharide units that have had functional groups replaced or removed. Polyphenols consist of a branched structure of multiple phenolic subunits. They can perform structural roles (e.g. lignin ) as well as roles as secondary metabolites involved in signalling , pigmentation and defense .
Biomolecules include large macromolecules such as proteins, carbohydrates, lipids, and nucleic acids, as well as small molecules such as vitamins and hormones. A general name for this class of material is biological materials. Biomolecules are an important element of living organisms.
The carbohydrate may be in the form of a monosaccharide, disaccharide(s), oligosaccharide(s), polysaccharide(s), or their derivatives (e.g. sulfo- or phospho-substituted). One, a few, or many carbohydrate units may be present. Proteoglycans are a subclass of glycoproteins in which the carbohydrate units are polysaccharides that contain amino ...
The sialic acid family includes many derivatives of the nine-carbon sugar neuraminic acid, but these acids rarely appear free in nature.Normally they can be found as components of oligosaccharide chains of mucins, glycoproteins and glycolipids occupying terminal, nonreducing positions of complex carbohydrates on both external and internal membrane areas where they are very exposed and develop ...
Bacteria and viruses are often lumped together as germs, and they share many characteristics. They’re invisible to the human eye. They’re everywhere. And both can make us sick, even kill us.
Lectins, or proteins that bind carbohydrates, can recognize specific oligosaccharides and provide useful information for cell recognition based on oligosaccharide binding. [ citation needed ] An important example of oligosaccharide cell recognition is the role of glycolipids in determining blood types .