The four levels of protein structure are distinguished from one another by the degree of complexity in the polypeptide chain. A single protein molecule may contain one or more of the protein structure types: primary, secondary, tertiary, and quaternary structure. 1. Primary Structure: describes the unique order in which amino acids are linked together to form a protein.
2. Secondary Structure: refers to the coiling or folding of a polypeptide chain that gives the protein its 3-D shape. There are two types of secondary structures observed in proteins. One type is the alpha (α) helix structure. This structure resembles a coiled spring and is secured by hydrogen bonding in the polypeptide chain. The second type of secondary structure in proteins is the beta (β) pleated sheet. This structure appears to be folded or pleated and is held together by hydrogen bonding between polypeptide units of the folded chain that lie adjacent to one another
3. Tertiary Structure: refers to the comprehensive 3-D structure of the polypeptide chain of a protein.
4. Quaternary Structure: is the structure of a protein macromolecule formed by interactions between multiple polypeptide chains. Each polypeptide chain is referred to as a subunit. Proteins with quaternary structure may consist of more than one of the same type of protein subunit.
Answer:
I'm pretty sure it is 'some species depend on disterbences'
It is important in determining whether injuries/death was an accident or purposeful, and if purposeful, who, how and why did someone do it. They determine the weapon through the ligature marks left, the shape, force and impact of the injury, the location of the injury, and by analysing any fragments and trace evidence left on the wound
Greenhouse gases are naturally occurring gases that are also produced as a result of human consumption, such as the burning of fossil fuels. They are essential to life in that a gas such as carbon dioxide (Co2) is essential to photosynthesis and the production of oxygen which helps to sustain life. However, the levels of greenhouse gases are far outreaching their natural limits and are having a negative impact on human and animal life.