Answer:
B) binding of a molecule to a binding site affects the binding properties of another site on the protein.
Explanation:
In an allosteric interaction between a protein and a ligand, the ligand binds to a site in the protein. As a result, there is a change in the properties of other active sites on the protein. These active-site changes may or may not allow the protein to bind to other molecules. There is a change in the protein that affects the affinity of the active site for other molecules. The affinity on the active site increases if the protein binds to an activator and decreases if the protein binds to an inhibitor molecule.
People who use complex tools like plows, irrigation, and fertilizers to grow domesticated plants are called farmers, it is a large scale activity and it´s use to obtain food from the earth, we also have horticulture, does not require hundreds or thousands of acres of land, horticulture is also important, but is more limited to the domestic and individual context, and finally it is much cheaper because it is not done at large scales like the Agriculture.
Answer:
By definition, tissues are absent from unicellular organisms. Even among the simplest multicellular species, such as sponges, tissues are lacking or are poorly differentiated. But multicellular animals and plants that are more advanced have specialized tissues that can organize and regulate an organism’s response to its environment.
Answer: The DNA on the paternal copy of the chromosome will be methylated at the imprinting center, while the DNA on the maternal copy of the chromosome will not be methylated in this region.
Explanation:
Chromosomes are DNA structures associated with proteins such as histones. They are found in the nucleus of cells and contain genetic information for the development and functioning of an organism. Human beings are diploid, meaning that they possess two copies of each of the 23 chromosomes (a total of 46).
Gametes, which are sex cells such as the sperm (produced by the male) and the egg (produced by the female) that are haploid. This means that they possess only one chromosome of each pair. During fertilization, a male gamete fuses with a female gamete to generate a zygote, which will give rise to a new human being. <u>This new individual will possess half of the genetic material from its father and half from its mother. Thus having a total of 46 chromosomes, 23 from each parent</u>.
Genetic imprinting modulates gene expression by chemical modification of DNA and/or modification of chromatin structure. Often, genetic imprinting causes a gene to be expressed only on the chromosome inherited from one of the parents. One example of imprinting is DNA methylation, which is a process by which methyl groups are added to DNA. <u>Methylation modifies DNA function when found in the promoter gene, repressing gene transcription. This means that a methylated gene will not be expressed</u>, that is, it will not produce a protein encoded by that gene. So, if a region of DNA is imprinted in the sperm cell, the paternal chromosome inherited from this sperm will be methylated in the genes of the offspring. And the offspring will only express the maternal copy inherited, which will not be methylated.