Answer:
integumentery system
Explanation:
your skin is actually the first protection against illness-causing pathogens.
Chloroplast. Specifically in the thylakoids of the chloroplast
Answer:
The correct answer is D. Reduced levels of circulating estrogens.
Explanation:
Estrogens prevent the loss of calcium and ensure its proper mineralization, thus preventing the bones from becoming brittle, maintaining the consistency of the skeleton and preventing osteoporosis. Osteoporosis is a skeletal disease in which there is a decrease in bone mass density. Thus, the bones become more porous, the number and size of the cavities or cells that exist inside them increases, they are more fragile, they resist shocks worse and they break more easily. Menopause is the definitive cessation of ovarian function that, externally, results in the disappearance of the menses and usually occurs around 50 years (the interval goes from 45 to 55 years). It is the gradual loss of calcium in the bones, which accelerates in the first years of menopause due to estrogen deficiency. At the beginning of the disease, there are no symptoms and, as it progresses, there is a tendency to suffer fractures, which leads to a decrease in height.
Protein structure is the three-dimensional arrangement of atoms in a protein molecule. Proteins are polymers — specifically polypeptides — formed from sequences of amino acids, the monomers of the polymer. A single amino acid monomer may also be called a residue (chemistry) indicating a repeating unit of a polymer. Proteins form by amino acids undergoing condensation reactions, in which the amino acids lose one water molecule per reaction in order to attach to one another with a peptide bond. By convention, a chain under 30 amino acids is often identified as a peptide, rather than a protein.[1] To be able to perform their biological function, proteins fold into one or more specific spatial conformations driven by a number of non-covalent interactions such as hydrogen bonding, ionic interactions, Van der Waals forces, and hydrophobic packing. To understand the functions of proteins at a molecular level, it is often necessary to determine their three-dimensional structure. This is the topic of the scientific field of structural biology, which employs techniques such as X-ray crystallography, NMR spectroscopy, and dual polarisation interferometry to determine the structure of proteins.
Protein structures range in size from tens to several thousand amino acids.[2] By physical size, proteins are classified as nanoparticles, between 1–100 nm. Very large aggregates can be formed from protein subunits. For example, many thousands of actin molecules assemble into a microfilament.
A protein may undergo reversible structural changes in performing its biological function. The alternative structures of the same protein are referred to as different conformational isomers, or simply, conformations, and transitions between them are called conformational changes.
An atrophic factors is a force that causes a cell to die, only natural forces on the cell are considered to be atrophic factors,whereas, and agents of mechanical or chemical abuse or lists of the cell are considered not to be atrophic factors. Which affect decrease workload loss of Innervation and diminishes your blood supplies , inadequate nutrition, and loss of enforce in stimulation and senility with compression.