Answer:
The options:
A) esophagus
B) stomach
C) small intestine
D) mouth
The CORRECT ANSWER IS B)
B) stomach
Explanation:
The digestive tract — often termed the gastrointestinal tract or alimentary canal — supplies the route via which foods passes through the body. In the course of this pathway, foods are digested into its constituents nutrients necessarily for absorption.
Digestion initially starts in the mouth, with enzymes in saliva dissolving carbohydrate (starch). In the course of chewing, the food is lubricated, a little bit of hear is used up, and less difficult to swallow and digest. The teeth and mouth aid conversion of each morsel of food to a bolus which flows right into the esophagus (“gullet”). In the course of chewing, taste buds stationed in the mouth gives pleasure to every mouthful — or to taste if not okay. Once the bolus is swallowed, it flows through the esophagus, it is kind of warmed and lubricated as it flows into the stomach.
Note:
The acidic condition of the STOMACH and the effect of gastric enzymes turns the bolus to CHYME, A LIQUEFIED MASS that is moved from the stomach to the small intestine.
Hydrogen bonds can form between regions of polar molecules that are <span>oppositely charged.
Source credit: </span>https://quizlet.com/16761990/biology-chapter-22-saud-flash-cards/
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.
Atoms come together to form molecules because of their electrons. Electrons can join (or bond) atoms together in two main ways. When two atoms share electrons between them, they are locked together (bonded) by that sharing. These are called covalent bonds
