Questions

The presence of vitamin D in the body enhances the absorption of calcium by the intestine.

without this centripetal force, circular motion is not possible. It acts radially towards the centre and if this force is removed there will be no circular motion but the revolving body will fly off at a tangent.

The endomembrane system is composed of the different membranes that are suspended in the cytoplasm within a eukaryotic cell. These membranes divide the cell into functional and structural compartments or organelles. In eukaryotes, the organelles of the endomembrane system include the nuclear membrane, the endoplasmic reticulum, the Golgi apparatus, lysosomes, vesicles, endosomes and the cell membrane, among others.

Nucleotides are the building blocks of the DNA and RNA used as genetic material. Nucleotides also are used for cell signaling and to transport energy throughout cells.

Both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are made up of nucleotides which consist of three parts::

1. Nitrogenous Base
2. Pentose Sugar
3. Phosphate Group.

Many carbohydrates contain one or more modified monosaccharide units that have had one or more groups replaced or removed.

Chitin is one of many naturally occurring polymers. It is one of the most abundant natural materials in the world. Over time it is bio-degradable in the natural environment. Its breakdown may be catalyzed by enzymes called chitinases, secreted by microorganisms such as bacteria and fungi, and produced by some plants.

Chitin is composed of repeating units of N-acetylglucosamine, a nitrogen-containing form of glucose.