BIO 105 Exam 1 Review Questions And Answers

Define Biology - ANS study of living things Know the steps in the scientific method - ANS 1. Observation 2. Question 3. Hypothesis 4. Experiment 5. Analyze 6. Hypothesis- True 7. Report results *6. Hypothesis-Fasle *7. Revise hypothesis Recognize what science can and cannot investigate - ANS it can investigate reasoning: why, how, what... cannot investigate right or wrong What special aspect determines an element's properties - ANS number of protons and neutrons Know how to determine the number of protons, electrons, and neutrons in an element by its entry in the periodic table - ANS Atomic # (top)- protons Atomic mass (bottom)- sum of protons & neutrons Period (columns)- # of shells (2 in first, up to 8 in others) Group (rows)- # of electrons in outer shell Know what an isotope is - ANS atoms of the same element that diiffer in number of neutrons Know the 4 major and 4 trace elements important to life - ANS Carbon, oxygen, hydrogen, nitrogen Calcium, phosphorus, potassium, sulfur Know what a valence is - ANS outer shell Know the properties of covalent bonds - ANS when 2 atoms share electrons in order to have a completed outer shell How they form (covalent) - ANS atoms sharing valence shell electrons to balance The different kinds there are (covalent) - ANS single, double, triple Know the example of a triple bond (Triyne) and what it does - ANS share 3 electrons in outer shells Know what a polar covalent bond is - ANS one atom takes more e's instead of sharing What causes that polarity - ANS opposite charges @ opposite poles- electronegativity The major example of a polar covalent molecule - ANS water Know how an ionic bond forms - ANS valence shell wants 8 e's, so steals one Terms Ion, Cation, & Anion - ANS ion- charged atoms (negative or positive) cation- positvie - more protons than electrons anion- negative- more electrons than protons Know what a hydrogen bond is - ANS non covalent attraction b/t hydrogen & electronegative atom Know the 4 properties of water - ANS cohesion, ice floats, universal solvent, temperature moderation What is cohesion? - ANS sticking; bonding What 2 properties does cohesion produce? - ANS adhesion & surface tension Give an example that illustrates all three of those properties - ANS water skipper "walking on water" Why some molecules are soluble and some aren't - ANS b/c of their charge (polarity) What is an acid? - ANS high H+ concentration What is a base? - ANS low H+ concentration Give one example of a base accepting H+ ions - ANS Ammonia in water Give one example of a base donating OH- ions - ANS NaOH Know the pH scale - ANS scale for # of hydrogen ions in a solution acidity - basicity 0-14 What does a buffer do? - ANS a chemical /combo chemicals that keeps pH w/i normal limits How does it do it (what does it do with H+ ions)? - ANS donates or accepts H+ ions Name one to two examples of where you can find buffers in nature- - ANS human blood stomach acid What is organic chemistry? - ANS study of carbon compounds What is the most important ingredient in living things? - ANS carbon Be able to tell me what structures they always come in and what element they always have attached - ANS a chain or ring structure hydrogen attached Know the 4 important functional groups and what they are - ANS hydroxyl, carboxyl, amino acids, phosphates Define monomer, polymer, and macromolecule - ANS monomer- small molecule, make up polymer eg glucose polymer- long chains of monomers macromolecule- large complex critical How are polymers made and destroyed? - ANS creation- uses all the water up destroyed- add water to break up What are the four classes of macromolecules? - ANS Carbs, lipids, proteins, nucleic acids What are the three types of carbohydrates? - ANS mono,di, & poly saccarides What are the two important functions of carbohydrates? - ANS energy storage store and release energy What is the most common & most important monosaccharide? - ANS glucose- used in respiration Give one example of a disaccharide - ANS sucrose- table sugar Give one example of a storage and one example of a structural polysaccharide - ANS storage- starch structural- cellulose