| Question |
Answer |
| Micro week 2, Sep 18,07 pages 12-13. |
VIRUSES, VIROIDS, PRIONS. |
| q. What are non-living elements called agents(not organisms) that usually consist of only a few molecules found in living cells? |
a. Viruses, Viroids, Prions. |
| q. What contains a protien coat surrounding nucleic acid? |
a. Viruses. |
| q. What must have host machinery to replicate and are inactive outside of host? |
a. Viruses termed OBLIGATE INTRACELLULAR PARASITES. |
| q. Can all forms of life be infected by viruses? |
a. Yes. |
| What freqently kills its host cells? |
a. Viruses |
| q. What contains no protective protein coat, consists of a single short piece of RNA, require host cell for replication and generally cause plant diseases? |
a. Viroids. |
| q. What are Prions? |
a. infectious proteins that contain no nucleic acids. |
| q. what are prions responsible for? |
a. neurodegenerative diseases. |
| q. What are viruses measured in? |
a. nanometers |
| q. What are bacteria measured in? |
a. micrometers |
| micro 9-27 pg14-27 |
(blank) |
| Macromolecules consist of repeating subunits called ? |
a. monomers. |
| q. what are the three major classes of biologically important macromolecules? |
a. proteins, polysacchrides(carbohydrates), lipids, nucleic acids. |
| q. RNA and DNA are composed of monomers and polymers called? |
a. nucleotides and polynucleic acids. |
| q. what are large molecules formed by joining together the same molecules(subunits)? |
a. Polymers, all macromolecules are polymers. |
| q.Joining subunits. what involves a chemical reaction in which H20 is removed? |
a. Dehydration synthesis. |
| q. what is the reverse of dehydration? |
a. Hydrolytic reaction |
| q. the major constituent of most cells is >50% _____________. |
a. dry weight. |
| q. the function of a protein is determined by what? |
a. its shape. |
| q. two amino acids are joined by what kind of synthesis reaction? |
a. dehydration synthesis reaction. |
| q. what is a Primary sturcture? |
a. a sequence of amino acids, in large part determines other protein features. |
| q. Describe a secondary structure. |
a. primary structure folds into a new configuration. the new configuration forms from weak bonds formed between amino acids. |
| q. Describe a tertiary structure. |
a. three dimensional structure with two major shapes. either a Globular or a Fibrous. |
| q. when does a protein become a functional protein? |
a. when it becomes a tertiary structure. |
| q. what is two or more proteins joined together to form a multimeric protein? |
a. Quaternary |
| what is a dimer? |
a. a two protein Quaternary structure. |
| q. what is a trimer? |
a. a three protein quaternary structure. |
| q. what is a shape change that causes protein to stop functioning? |
a. Denaturation. |
| q. what dertermines if denaturation can be reversible or not? |
a. environment determines reversibility. |
| q.what are the four important roles carbohydrates play in all organizms? |
a. store energy, for energy, form part of nucleic acids, form part of bacterial cell wall. |
| q. carbohydrates contain carbon, hydrogen and oxygen in a _______________ ratio. |
a. 1:2:1 ratio |
| q. what is a large molecuel made of carbohydrate molecules? |
a. Polysaccharide. |
| q. what are short chains of carbohydrates? |
a. Disaccharide |
| q. what is a monosaccharide? |
a. a single carbohydrate molecule. |
| q. how are monosaccharides classified? |
a. by number of carbons in molecule. |
| q. what are the most common monosaccharides? |
5 and 6 carbon sugars |
| q. 5 carbon sugars are called? |
a. pentose |
| q. some examples of pentose are? |
a. Ribose and deoxyribose. |
| q. what is a six carbon sugar? |
a. Hexose |
| q. what are three examples of hexose? |
a. Glucose, furctose and glactose. |
| q. what is produced by joining two monosaccharides through dehydration synthesis? |
a. Disaccharides |
| q. what are the two most common disaccharides in nature? |
a. Lactose and Sucrose |
| q. Glucose+ gaLactose= |
a. Lactose |
| q. Glucose + fructose = |
a. sucrose |
| q. Glucose + glucose = |
a. maltose |
| q.what are three functions polysaccharides serve? |
a. Polysaccharides serve as Cellulose, Glycogen, and Dextran. |
| q. what is the most abundant organic molecule on earth? |
a. Cellulose |
| q. what is a polymer of glucose molecules and is the principle constituent in plant cell walls? |
a. Cellulose |
| q. what is the corbohydrate storage molecule of animals and some bacteria and is a polymer of glucose subunits? |
a. Glycogen |
| q. what is a storage molecule for carbon and energy for some bacteria and is a polymer of glucose subunits? |
a. Dextran |
| starch is also a polysaccharide made up of glucose subunits. |
(blank) |
| q. what is only slightly soluble in water but is very soluble in organic solvents such as ether, benzene, and chloroform. |
a. Lipids, due to their hydrophobic nature. |
| q. Simple lipids contain carbon, hydrogen, and oxygen. the most common are the fats, which are a combination of _____________ and __________________. |
a. fatty acids and glycerol (triglyceride). |
| q. what is a monoglyceride? |
a. only one fatty acid bound to a glycerol. |
| q. what is a Diglyceride? |
a. two fatty acids joined together. |
| q. Unsaturated fats are hydrocarbon protions containing at least one double bond and are ____________ at room temp. often called oils. |
a. liquid. |
| q. Polyunsaturated fats have several dbl bonds, some examples include? |
a. sunflower oil, safflower oil, and corn oil. |
| q. All members of the steroid grp have a four membered ring structure and if a hydroxyl grp is attached to one of the rings, the steroid is called a ____________. |
a. a Sterol is a steroid with a hydroxyl added to it. |
| q. where are sterols found? |
a. sterols are found in cytoplasmic membrane of eukaryotic cells. |
| q. What contain fatty acids and glycerol as well as elements other thatn carbon, hydrogen and oxygen? |
a. Compound lipids, exp. include phospholipids, lipoproteins etc. |
| q. Phosphate is linked to a variety of other polar molecules, such as alcoohol, sugar, or certain amino acids. This is refered to as a ______ _________ ___________. |
a. a polar head group. |
| q. What is a long chin fatty acid linked covalently to a long chain alcohol by an ester bond? |
a. Waxes |
| q. why are waxes completely insoluble? |
a. they do not have hydrophilic heads thus are completely water insuluble. |
| q. what makes Mycobacterium tuberculosis resistant to drying? |
a. it is surrounded by a waxy wall (Mycolic acid) |
| q. what are two types of nucleic acid? |
a. DNA ( carrie genetic code in all cells) and RNA( decodes sequence of amino acids to produce proteins). |
| q. what are the sub units of nucleic acids? |
a/. the subunits of nucleic acids are nucleotides. |
| q. how is DNA information stored? |
a. in sequence of nucleotides. |
| q. what are composed of a nitrogenous base, a five carbon sugar molecule and a phosphate molecule? |
a. Nucleotides are composed of these three units. |
| q. the nitrogenous base contains purines and pyrimidines. |
(blank) |
| q. what are the two purines? |
a. Adenine and Guanine. |
| q. What are the Pyrimidines? |
a. thymine and cytosine |
| q. Nucleotides are joined through what kind of bonds? |
a. covalent |
| q. how is the bond created between the phosphate of one nucleotide and the sugar of the adjacent nucleotide? |
a. through dehydration synthesis. |
| q. what acts as a bridge between the number 3 carbon of one sugar and the number 5 carbon of the adjacent? |
a. Phosphate molecule, resulting in a sugar phosphate backbone. |
| q. DNA in living organisms is a double stranded helicle molecule, strands are held together by hydrogen bonding between ? |
a. the nitrogen bases. |
| q. In the specific pairing between bases Adenine binds to _____________. |
a. Thymine A-T or T-A |
| q. Guanine binds to ______________. |
a. Cytosine G-C or C-G, remember bases are complementary. |
| Remember RNA is a single stranded molecule involved in what? |
a. RNA is involved in decoding DNA. |
| q. RNA structure is similar to DNA but differs in at least 4 ways, what are they? |
a. Thymine is replaced by uracil(there is no thymine base in RNA), the sugar is ribose in place of deoxyribose, RNA is generally shorter, it exists as a single stranded molecule not double stranded. |
| RNA is for protein synthesis. |
(blank) |