Answer:
A DNA marker
Explanation:
also known as a size standard or a DNA ladder) is loaded into the first well of the gel. The fragments in the marker are of a known length so can be used to help approximate the size of the fragments in the samples.
The number of electrons/protons (both are the same number) is equal to the atomic number.
Brainliest please :)
In biochemistry, aligand is a substance that forms a complex with a biomolecule to serve abiological purpose. In protein-ligandbinding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein.
Receptor mediated endocytosis is an endocytotic mechanism in which specific molecules are ingested into the cell. The specificity results from a receptor-ligand interaction. Receptors on the plasma membrane of the target tissue will specifically bind to ligands on the outside of the cell. An endocytotic process occurs and the ligand is ingested.
A very well studied example of receptor mediated endocytosis involves the metabolism of cholesterol.
A water molecule consists of two atoms of hydrogen linked by covalent bonds to the same atom of oxygen. Atoms of oxygen are electronegative and attract the shared electrons in their covalent bonds.