Question

need help for questions 21, 23, and 24

21. For a eukaryotic cell (an animal), an excess of glucose would be stored as g glucose would be stored as glycogen by a) glycogen lysis enzymes in liposomes an enzyme that binds to cellulose, c) storage in the Golgi apparatus, d) glycogen stored in the mesosomes that contaln dehydration synthesis enzymes, e) by organelles that contain dehydration synthesis enzymes 22. The molecule ATP is important because it is the energy source for: a) synthesis of a polypeptide by the rRNA. b) transpot of molecules across the cell membranes during active transport. c) enzymes to change shape during dehydration synthesis d) enzymes to change shape during enzymatic hydrolysis, e) All of the choices 3 When a prokaryotic or a eukaryotic cell is placed in a hypertonic solution, the net movement of H-0 would occur through the process of: A) diffusion through the fatty acid layer of the phospholipid bilayer out of the cell, B) active transport proteins, C) active transport into the cell through portal proteins, D) phagocytosis, E) diffusion out of the cell hrough portal proteins. 24) In eukaryotic cells like the Alpha cells of the pancreas, Glucagon (a protein hormone) is released and causes liver cells to release glucose. Which of the following is NOT true? A) The sequence of amino acids in Glucagon is determined by a gene, B) the e Glucagon regulates the level of blood glucose, it is released from the cell by the Golgi apparatus. D) Glucagon is manufactured polypeptide (Glucagon) is formed by the ribosome using mRNA as the directions and is inserted into the rough endoplasmic reticulum.C) Becaus in the nucleus. E) all are true

Answer 1

21.

Answer: e) Organelles that contain dehydration synthesis enzymes.

Explanation: The excess glucose in animal cells are stored in the form of glycogen. Glucose are monomers or monosaccharides that combines ( many glucose molecules) to form a polysaccharide (say cellulose/glycogen/starch). During the process, one monomer gives a OH (hydroxyl group) while the other gives a H (Hydrogen) thereby giving a H2O ( Water molecule). Hence this process is named as dehydration synthesis and is accomplished with the help of dehydration synthesis enzymes. Thus, for the formation of glycogen from glucose requires dehydration synthesis enzymes and are stored in organelle that contain this enzyme.

23.

Answer: a) diffusion through the fatty acid layer of the phosphobilipid layer out of the cell.

Explanation: In a hypertonic solution, the concentration of the solution is higher (when a cell is placed in this solution, the concentration of the solution is higher than the cytosol). In order to balance the tonicity of both the solution (inside and outside of the cell), the water gushes out of the solution via a semipermeable membrane. The phosphobilipid layer acts as a best semipermeable membrane that helps in the process of diffusion.

24.

d) glucagon is manufactured in the nucleus.

Glucagon are hormone that are encoded by the GCG gene present in the DNA. The mRNA of this gene forms a precursor, from which repeated cleavage takes place to form a functional glucagon.