BSC 1020 Exam 1Questions With Correct Answers Solutions Guaranteed

List the seven characteristics of life as it is known on Earth. - Correct Answers Cells, metabolism, growth, reproduction, irritability, adaptation, movement Rank the levels of life from atoms and molecules to the biosphere - Correct Answers atoms, molecules, organelles, cells, tissues, organ and organ system, organisms, population, community, ecosystems, and biosphere What is the difference between EUKARYOTES and PROKARYOTES? Classify each of the following organisms as eukaryotic or prokaryotic: bacteria, Archea, protists, fungi, plants, and animals - Correct Answers eukaryotes are larger, more complex, nucleus is enclosed in a membrane, and contains many types of organelles prokaryotes are smaller, simpler structure, DNA is concentrated in nucleoid region without a membrane, and lacks most organelles What are the three domains of life? Which organisms belong to each domain? - Correct AnswersBacteria, archaea, and Eukarya Bacteria - prokaryotes Archaea - prokaryotes Eukarya - plants animals fungi What are Darwin's two main observations and his inescapable conclusion? - Correct AnswersObservation - overpopulation and competition, and individual variation Conclusion - unequal reproductive success Compare and contrast natural and artificial selection - Correct AnswersNatural causes adaptation and mechanism for evolution. It is used in survival Artificial is by humans and we select instead of environment Compare and contrast discovery science and hypothesis-driven science - Correct AnswersDiscovery Science - describes observations and used inductive reasoning and seeks natural causes for natural phenomenas Hypothesis-driven science - explains a set of observations. uses scientific method, deductive reasoning What are the steps of the scientific method? - Correct AnswersObservation, question, hypothesis, prediction, experiment, conclusion What is the difference between a scientific hypothesis, theory, and law? - Correct AnswersHypothesis - a proposed explanation for a set of observation Theory - much broader in scope than a hypothesis, a comprehensive explanation for a large number of observations and has varied and extensive evidence Law - must always apply under the same condition, also implies a casual relationship What is matter? What are its three physical states? - Correct AnswersMatter - Anything that has mass and takes up space Solid, liquid, gas What is an element? How many elements occur naturally? How many are essential for life? Which 4 elements are most abundant in living things (including humans)? What are trace elements? - Correct AnswersElement - substance that cannot be broken down any further 92 occur naturally 25 essential for life Carbon, hydrogen, nitrogen, and oxygen Trace elements - Elements that are important but not very abundant in the body: iodine, iron, fluorine What are compounds? - Correct AnswersCompounds are substances that contain two or more elements in a fixed ratio List the 3 main subatomic particles, their charge, and their location in the atom. - Correct AnswersProtons - Positive Neutrons - Neutral Electrons - Negative Define the atomic number and the mass number of an atom. If given these, be able to calculate the number of each subatomic particle. - Correct AnswersAtomic mass = # of protons Mass Number = protons + neutrons What are ions? What are ionic bonds? - Correct AnswersIons are charged atoms due to gain or loss of an electron Ionic bonds = Formed between two oppositely charged ions What are covalent bonds? What are hydrogen bonds? - Correct AnswersCovalent bonds - When two atoms share one or more pairs of electrons in the outermost shell Hydrogen bonds - Weak attractions between molecules in water between the oxygen and hydrogen Explain why the covalent bonds in H2O are polar covalent bonds. - Correct AnswersElectrons are not shared equally. This causes opposite charges on the ends like a negative O and a positive H What are the two components of a chemical reactions? - Correct AnswersProducts and reactants Why do water molecules stick to other water molecules? What is surface tension? - Correct AnswersHydrogen bonding of water molecules causes them to stick together in cohesion Surface tension - How difficult it is to break or stretch the surface of a liquid. Hydrogen bonds give water a very high surface tension What is the relationship between solution, solute, and solvent? - Correct AnswersSolute - Substance being dissolved Solvent - What the solute is being dissolved in Solution - A liquid with a homogeneous mixture with one or more substances What is an acid? A base? Complete the following sentence by circling the correct choice or filling in the blank with the correct term: "At lower pH's, there are more/less (circle one) _________ (aka __________ ions) present in the solution; at higher pH's there are more/less (circle one) ________ present in the solution." - Correct AnswersAcid - Chemical compound that released H+ ions in a solution Base - Chemical compound that accepted H+ ions in a solution Less, OH-, hydroxide, more, H+ What is the range of the pH scale? What is the pH of pure water (a neutral solution)? What is a buffer? - Correct Answers0 - 14 Water is 7 Buffer is a solution that can be used to maint/control pH.... weak acid weak base What are organic compounds? Why is carbon such a versatile atom? - Correct AnswersOrganic compounds - Molecule with carbon Carbon acts as an intersection from which an organic compound can branch off What is a hydrocarbon? What is the simplest one? - Correct AnswersSimplest organic compounds. Methane. What is a macromolecule? What are monomers and polymers? Which biological molecules form polymers? Contrast dehydration reactions and hydrolysis reactions? - Correct AnswersMacromolecule - Large biological molecules Monomers - Smaller molecules, used to create polymers Polymers - Large molecules created by stringing together monomers Dehydration - Used to link monomers together to form polymers. Chemical reaction that removes a molecule of water. Hydrolysis - Used to break down polymers. Cells break bonds between monomers by adding water to them. Opposite of dehydration. What are the four categories of large molecules? - Correct AnswersCarbohydrates, lipids, proteins, nucleic acfids What roles do carbohydrates play in humans? Define the terms monosaccharide, disaccharide, and polysaccharide. Give examples of each. - Correct AnswersCarbohydrates - source of dietary energy; monosaccharides - glucose, fructose; Simple sugars Disaccharide - lactose; Double sugar Polysaccharide - Starch, glycogen; Complex carbs Define hydrophilic and hydrophobic. - Correct AnswersHydrophilic - water loving Hydrophobic - water fearing What characteristic do all lipids share? What is a triglyceride? What is the function of lipids? - Correct AnswersLipids are hydrophobic Triglyceride - Glycerol molecule with three fatty acids Lipids store energy in reserves What is meant by saturated and unsaturated fats? - Correct AnswersSaturated - Only hydrogen molecules attached to carbon; Unsaturated - fewer than maximum amount of hydrogens attached (indicates presence of double/triple bond, ring, etc) What are steroids? Which compound are they made from? - Correct AnswersSteroid - Carbon skeleton bent into four fused rings; made of lipid compound What are the functions of proteins? Give specific examples. - Correct AnswersStructural (hair/horns) Storage (seeds, eggs) Contractile (enable muscles to contract) Transport (hemoglobin) Enzymes (cleaning products) What is a polypeptide? - Correct AnswersPolypeptide - A polymer of the building blocks of proteins amino acids What basic structure do all amino acids have? How many amino acids are used to build proteins? What type of bond links amino acids to each other? - Correct Answers20 amino acids are used to make proteins; peptide bonds link amino acids together Describe the four levels of protein structure. - Correct AnswersPrimary - Order and number of amino acids Secondary - Alpha and beta sheets; Hydrogen bonds between polypeptides Tertiary - 3D shape of the polypeptide Quaternary - two or more polypeptide chains What happens when a protein is denatured? - Correct AnswersUnfavorable change in temp, pH, or some other quality of the environment which causes a protein to unravel and lose its normal shape. What is the function of nucleic acids? - Correct AnswersMacromolecules that store information and provide instructions for building proteins What three parts does every nucleotide have? What are the four bases in DNA? - Correct AnswersPhosphate base, 5 or 6 carbon sugar, and a nitrogenous base; Thymine, Guanine, Adenine, and Cytosine Describe the structure of the DNA double helix. What makes up the backbone? Which bases are bonded to each other? - Correct AnswersDouble helix - A twisted ladder Sugar-phosphate backbone Nitrogenous bases connected by hydrogen bonds List the three main differences between DNA and RNA. - Correct AnswersDifferent sugar (DNA deoxyribose; RNA ribose) Different bases (Instead of Thymine in RNA, Uracil is marche with Adenine) RNA usually single stranded whereas DNA double stranded Give examples of unicellular and multicellular organisms. - Correct AnswersUnicellular Valonia ventricosa Synringammina fagilissima Thiomargarita namibiensis Multicellular Dog Cat Fish Human How are light microscopes used? Define magnification and resolving power. - Correct AnswersVisible light is projected through the specimen, glass lenses enlarge the image a