When stimulated, the stomach's environment is characterized as acidic. It secretes protease enzymes and hydrochloric acid to assist digestion. The hydrochloric acid keeps the pH low, enabling protease enzymes to effectively break down proteins. Following digestion, the stomach returns to its normal pH level. Therefore, acid secretion coincides with food presence to support proper digestion.
Answer:
Sister chromatids are identical copies of chromatids from chromosomes. They are typically produced through the semi-conservative replication of a single chromosome's DNA. Thus, they can be viewed as'photocopies' of the original parental chromosomes, linked together at the centromere.
They are entirely identical in every aspect, sharing the same genes and allele configurations.
Still, minor variations can occur between the identical sister chromatids due tomutations fromerrors during replication, and differences can also arise in the lengths of telomere repeats.
Non-sister chromatids differ as they arise from separate haploid sex cells during fertilization. These chromatids come from distinct parents and possess different genetic compositions since they do not lie on the same homologous chromosomes. This is why crossing-over results in genetic variation.
However, they may still exhibit genetic similarities if they are part of homologous chromosomes. This is because Synapsis of the bivalents in these chromosomes permits the exchange of genetic material through crossing-over between non-sister chromatids, thereby sharing identical genetic traits.
Explanation:
The potato does not increase in size because it is only a segment of the plant. Water absorbed from the soil is taken up by the roots and transported to other parts like leaves, but the potato itself does not directly absorb water from the soil.
The digestive activity is regulated by mechanical and chemical receptors found in the walls of the tract organs.
