Biology 101 Final Exam Verified Review Test

Biology 101 Final Exam Verified Review Test What is the lowest level of biological organization that can perform all the activites required for life? - Answer-Cell- For example, a skin cell Why is it important that an experiment include a control group? - Answer-To cancel the effects of unwanted variables, in order to assure that a particular result is due to the variable being tested or to some other factor. In experemintal prodcedures, repetition of the procedures__________. - Answer-is necessary before assuming that a given set of results is correct A hypothesis must be testable and falsifiable to be scientifically valid. Being testable and falsifiable means that_________. - Answer-some concievable observation or experiment could reveal wherther a given hypothesis is correct or incorrect The chemical properties of an atom depend on? - Answer-The number of electrons in its outermost shell. About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter? - Answer-carbon, hydrogen, nitrogen, oxygen True or false? Protons and electrons are electrically charged particles. Protons hav one ut of negative charge, and electrons have one unit of positive charge. - Answer-False Calcium has an atomic number of 20 and an atomic mass of 40. Therefore,a calcium atom must have___________. - Answer-20 Protons Each element is unique and different from other elemets because of te number of protons in the nuclei of its atoms. What indicates the number of protons in an atom's nucleus? - Answer-Atomic Number Different atomic forms of an element contain the same number of protons but a different number of neutrons. What are these different atomic forms called? - Answer-Isotopes A covalent chemical bond is one in which? - Answer-Outer-shell electrons of two atoms are shared so as to satisfactoril fill the outer electron shells of both atoms. What results from an unequal sharing of electons between atoms? - Answer-A polar covalent bond What results from a transfer of electron(s) between atoms? - Answer-Ionic Bond Sometimes atoms form molecules by sharing two pairs of valence electrons. When this occurs, the atoms are said to be joined by? - Answer-A double covalent bond The slight negative charge at one end of one water molecule is attracted to the slight positive charge of another water molecule. What is this attraction called? - Answer-A hydrogen bond What type of bond must be broken for water to vaporize? - Answer-Hydrogen Bond Hydrophobic substances such as vegetable oil are_________. - Answer-nonpolar substances that repel water molecules Which of the following solutions is the most acidic? tomato juice at pH4 gastric juice at pH2 household bleach at pH12 black coffee at pH5 - Answer-gastric juice at pH2 What is the pH of a solution with a hydrogen ion [H+] concentration of 10-6 M? - Answer-pH6 How many electron pairs does carbon share in order to complete its valence shell? - Answer-4 Describe geometric isomers. - Answer-They have variations in arrangement around a double bond. A compound contains hydroxyl groups as its predominant functional group. It should dissolve in water, is this true? - Answer-Yes, it is true What is the chemical mechanism by which cells make polymers from monomers? - Answer-Deydration reactions A disaccaride is formed when a dehydration reaction joins two monosaccarides. True or false? - Answer-True Lipids, they are soluble in water. True or false? - Answer-True The a helix and the B helix pleated sheet are both commen polypeptide forms found in what level of protein structure? - Answer-Secondary Which of the following best describes the flow of information in eukaryotic cells? RNA--->proteins-----> DNA proteins------>DNA------>RNA DNA---->RNA---->proteins DNA------>proteins----->RNA - Answer-DNA----->RNA------>proteins DNA is composed of building blocks called_________. - Answer-nucleotides In the double helix structure of nucleic acids, cytosine hydrogen bonds to________. - Answer-guanine The two strands of a DNA double helix are held together by_________ that form between pairs of nitrogenous bases. - Answer-hydrogen bonds In what polysaccharide form do plants store glucose to be available later as an energy source? - Answer-Starch Carbohydrates are used in our bodies mainly for_________. - Answer-energy storage and release Which is the term for compounds that DO NOT mix with with water? - AnswerHydrophobic Enzyme molecules require a specific shape to perform their catalytic function. What might alter the shape of an enzymatic protein? - Answer-Denaturing the protein. A change in salt concentrations of pH. Heating and protein. Protein molecules are polymers (chains) of ________. - Answer-amino acid molecules What is the name of a diverse group of hydrophobic molecules? - Answer-Lipids What stores and transmits genetic information? - Answer-Nucleic acids Phospholipid molecule___________. - Answer-has hydrophilic head and hydrophobic tails Saturated fatty acids______. - Answer-do not have double bond Large numbers of ribosomes are present in cells that specialize in producing what molecules? - Answer-Proteins What structure is the site of the synthesis of proteins that may be exported from the cell? - Answer-Rough ER Which structure is primarily involved in detoxificaion of many poisons and drugs? - Answer-Smooth ER What is one of the main energy transformers of cells? - CONTINUES...