Chapter 5 - Practice Questions - BIOL - TAMU - GradeBuddy
Two of these processes, dehydration and hydrolysis, help your body build large Dehydration Synthesis: Definition, Reaction & Examples. b in hydrolysis you ADD H2O. OH goes on one end and H goes on the other end in dehydration you remove the OH and H from 2 separate. The difference between a polar (water) and nonpolar (ethane) molecule is due to the unequal . Hydrolysis (hydration) reactions break down polymers in reverse of .. Questions and answers along with clear tutorials about large molecules.
Hence, biological catalysts, or enzymes that speed up chemical reactions are needed. Along with that, the type of dehydration synthesis is named after the catalyst that drive the reaction. Based on the product formed As mentioned earlier, dehydration synthesis can produce a wide variety of polymer products. Therefore, these types of reactions are grouped whether they form complex carbohydrates from simple sugars, create fatty acids from Acetyl-CoA, and others.
Relative to the process of dehydration synthesis, hydrolysis is merely the reverse. Using water molecules complex molecules are broken down into smaller units.
Large molecules are broken down by breaking the bond between water molecules.
Introduction to macromolecules (article) | Khan Academy
Examples of hydrolytic reactions are the breaking down of complex sugars, proteins, complex fats, and nucleic acids into monosaccharides, amino acids, fatty acids, and nucleotides. Types of Hydrolysis Various types of hydrolysis occur in living organisms.
The three types are listed below: Salt Hydrolysis This occurs when a salt when a salt is dissolved in water. Acid Hydrolysis According to the Bronsted-Lowry theory, water can act as either an acid or a base. Base Hydrolysis In relation to what was mentioned above, the water molecule can act as a base and hydrolyze molecules. PET is formed by dehydration synthesis from two monomers — ethylene glycol and teraphthalic acid.
In biological systems, dehydration synthesis reactions occur in every cell, especially since it is important for the formation of ATP. Nearly all biopolymers are also derived from this reaction. Formation of Glycosidic Bonds Glycosidic bonds are covalent bonds formed between a carbohydrate and any other molecule.
Many of these involve a dehydration reaction. When maltose is formed from glucose, there is a glycosidic bond between two glucose molecules with the release of one molecule of water. Long polymers of glucose can be formed in a similar manner through a series of dehydration reactions to give rise to starch, cellulose or glycogen based on the position of the glycosidic bonds.
Other disaccharides like sucrose and lactose are also formed through dehydration reactions between two monosaccharides. Additionally, glycosidic bonds are also involved when a carbohydrate is modified. Here, a glucose molecule is reacting with methanol to give rise to ethyl glucoside.
Triglyceride Formation One of the intermediates of carbohydrate and fat metabolism is acetyl coA, a molecule where a two-carbon acetyl group is attached to coenzyme A. These fatty acids then form triglycerides, which are an important energy storage molecule. Triglycerides derive their name from the fact that all three hydroxyl groups on glycerol undergo esterification with fatty acids.
Each of the three fatty acids undergoes a dehydration reaction with the alcohol moieties on glycerol to generate one molecule of triglyceride. One of the main reasons why triglycerides are considered a better storage medium than carbohydrates is their high energy density.
They have a larger proportion of carbon atoms that can undergo oxidation and contain fewer oxygen molecules because fatty acids are generated from hydrocarbons. The removal of three water molecules in the process of forming a triglyceride further increases the energy density of the molecule. In this image, R1, R2 and R3 refer to long chain hydrocarbons, each of which is attached to a carboxylic acid functional group. Hydrolysis Hydrolysis is the reverse of a dehydration reaction because it involves the breaking of a covalent bond through the addition of a molecule of water.
Hydrolysis is catalyzed by a large group of enzymes called hydrolases. Among the most commonly known hydrolases are digestive enzymes.
Digestion begins from the mouth, where salivary amylase breaks down starch molecules. This is why extended chewing of starchy foods gives rise to a sweet taste in the mouth. The action of salivary amylase generates monosaccharides. This is followed by the action of proteases in the stomach that begin the process of breaking peptide bonds in proteins.
Digestion is continued by hydrolytic enzymes from the pancreas and small intestine acting on lipids, carbohydrates, nucleic acids and proteins.
Each of these hydrolases has a specific name depending on the nature of its substrate. For instance, lipases act on lipids and nucleases on nucleic acids. A protease that severs peptide bonds from one end of the protein is called an exopeptidase and those that act on internal bonds are called endopeptidases.
Similar enzymes are also present for intracellular digestion within lysosomes. Additionally, there are specific enzymes that can reverse the post-translational modifications of proteins, such as phosphatases.
These enzymes remove the phosphate group attached to a protein through a hydrolysis reaction. Similarly, ATPase enzymes catalyze the hydrolysis of the terminal phosphodiester bond in ATP, and are important for releasing the energy stored in the molecule. Many enzymes involved in hydrolysis contain a serine residue in their active site and are therefore known as serine hydrolases. These include most digestive enzymes and those involved in major metabolic pathways within the cell.
Related Biology Terms Aldol Condensation — A reaction in which a molecule containing a carbon-carbon double bond and an alcohol group reacts with a carbonyl compound through a dehydration reaction. Disaccharide — A sugar formed from two monosaccharides through a condensation reaction.
Nucleophile — A reagent that is capable of donating a pair of electrons to an electrophile. Transesterification — A reaction where the organic group of an ester is exchanged with the group of another alcohol. Which of these involves the formation of an ester linkage through dehydration synthesis? Creation of polyethylene terephthalate from ethylene glycol and teraphthalic acid B.
Creation of glycosylated carbohydrates C. Creation of a peptide bond between two amino acids D. All of the above Answer to Question 1 A is correct. Polyethylene terephthalate is a synthetic polyester that was first isolated from turpentine.
It is used to create fabrics, ropes and bottles. Glycosylation and peptide bond formation are examples of condensation reactions that involve the loss of one molecule of water.
However, they do not result in the formation of an ester. Which of these enzymes is involved in reversing the effects of a dehydration reaction?
Protein kinase that catalyzes the phosphorylation of a protein B. DNA polymerase that catalyzes the formation of polynucleotide C. Proteases that are involved in the digestion of proteins in the gastrointestinal tract D.