It is a less invasive surgery, so your recovery time is shorter and easier than with mastectomy. Lumpectomy has a few potential disadvantages: You are likely to have 5 to 7 weeks of radiation therapy, 5 days per week, after lumpectomy surgery to make sure the cancer is gone.
DNA: Double Helix. The secondary structure of DNA is actually very similar to the secondary structure of proteins. The protein single alpha helix structure held together by hydrogen bonds was discovered with the aid of X-ray diffraction studies. The X-ray diffraction patterns for DNA show somewhat similar patterns.
Humans have tens of thousands of different proteins, each with a specific structure and function. Proteins are the most structurally complex molecules known. Each type of protein has a complex three-dimensional shape or conformation. All protein polymers are constructed from the same set of 20 amino acid monomers. Polymers of proteins are called polypeptides. A protein consists of one or more polypeptides folded and coiled into a specific conformation. Amino acids are the monomers from which proteins are constructed. Amino acids are organic molecules with both carboxyl and amino groups. 1  At the center of an amino acid is an asymmetric carbon atom called the alpha carbon. 2  Four components are attached to the alpha carbon: a hydrogen atom, a carboxyl group, an amino group, and a variable R group (or side chain).