Plants and animals could not live without nitrogen<span>. It is an </span>important<span> part of many cells and processes such as amino acids, proteins, and even our DNA. It is also needed to make chlorophyll in plants, which plants use in photosynthesis to make their food and energy. hope this helps!</span>
A cell is the smallest basic unit of life
The answer is tunicates. Tunicates are commonly known as sea squirts and are in the Chordata phylum, even though they don't have a back bone. Which is really weird. But they just got put into the same category as humans. This is because they have a notocord and a back bone when they are larvae. But they lose all these when they become adults.
Answer:
tertiary; quaternary
Explanation:
The orientation of all the atoms of a protein in three dimensions represents its tertiary structure. It includes the folding of the polypeptide chains in a way that brings are far apart amino acids of its secondary structure close together. Various segments of a polypeptide chain interact to form tertiary structures and these segments are held together by different kinds of weak interactions.
However, disulfide cross-links between the segments of polypeptide chains also stabilize the tertiary structure of some proteins. Likewise, disulfide bonds also hold the protein subunits of some proteins together and thereby, contribute to the quaternary structure. For example, two light chains of an antibody are joined together by disulfide bonds.
