Yes that's right, its True, are structures that have specific functions
Answer:
The options A, B, and D are all valid.
Explanation:
- The reason is that some proteins require molecular chaperones if they are to fold properly within the environment of the cell. In the absence of chaperones, a partially folded polypeptide chain has exposed amino acids that can form non-covalent bonds with other regions of the protein itself and with other proteins, thus causing nonspecific aggregation of proteins.
- The option A) is correct because the protein you are expressing in bacteria is being made in large quantities, it is possible that there are not enough chaperone molecules in the bacterium to fold the protein. Expressing the protein at lower levels might increase the amount of properly folded protein.
- The option B) is correct as urea should solubilize the protein and completely unfold it. Removing the urea slowly and gradually often allows the protein to refold. Presumably, under less crowded conditions, the protein should be able to refold into its proper conformation.
- The option C) is not correct as treating the aggregate with a protease, which cleaves peptide bonds, will probably solubilize the protein by trimming it into pieces that do not interact as strongly with one another; however, chopping up the protein will also destroy its enzymatic activity.
- The option D) is correct because overexpressing chaperone proteins might increase the amount of properly folded protein.
- The option E) is not correct as heating can lead to the partial denaturation and aggregation of proteins to form a solid gelatinous mass, as when cooking an egg white, and rarely helps solubilize proteins.
Answer:
selective interference
Explanation:
Natural selection acts on genes that are inherited together, which is the case for species of asexual reproduction (where genes are inherited together by clonal offspring). In asexual species, linkage disequilibrium (i.e., non-random association of the alleles of different <em>loci</em>), can be understood in a similar mode in terms of population allele frequencies. Selective interference underlies the association between beneficial mutations and surrounding sites which are subject to deleterious mutations. It has been shown that asexual species adapt at a slower rate than species of sexual reproduction. In sexual species, selective interference could be bypassed through the mechanism of recombination during meiosis (although there is not conclusive evidence of this). In asexual species, different deleterious and beneficial mutations are generally fixed, whereas beneficial mutations are generally spread and fixed in species of sexual reproduction.
The respiratory and circulatory systems are close together by working and relying with each other. The respiratory system imports oxygen from the air and that oxygen goes through out the body by the circulatory system pumping the oxygen. That creates carbon dioxide, which the respiratory exports from the body.
Answer:
Carrier proteins move materials from one side of the cell membrane to the other. This is useful for both active transport, meaning you have to transport against the concentration gradient, and facilitated diffusion, a form of passive transport.
