7. Chlorine has an atomic number of 17, how many electrons does it have in its outermost (third) shell? a. 7 c. 2 e. 8 b. 4 d. 10

Transcription

1 Multiple Choice: 1-32 (1.5 points each). Circle the best answer here and fill in your bubble sheet. This portion of the exam will be graded using the bubble sheets only. 1. According to modern science, life began about years ago and the Eukaryotic cell formed years ago. a. 4.6 billion, 6 thousand c. 4.6 billion, 5-9 million e. 6 thousand, 3 thousand b. 3.5 billion, 1-2 billion d. 46 million, 12 million 2. Approximately what percentage of the Earth's water is Fresh water? a. 75% c. 3% e. 68.5% b. 25% d. 97% 3. What are the two most abundant elements in our Sun and in the Universe? a. Hydrogen, Helium c. Hydrogen, Oxygen e. Hydrogen, Carbon b. Oxygen, Nitrogen d. Oxygen, Helium 4. Ozone forms when: a. CO 2 and O 2 combine c. O 3 combines with CO 2 e. O 2 combines with O b. O 3 combines with O d. CO 2 and O combine 5. The Ozone layer protects the Earth from: a. Comets c. Global warming e. Protons thrown from the sun b. Sun's magnetic field d. Ultraviolet radiation 6. Which subatomic particles are always equal in electrically neutral atoms? a. Electrons and neutrons c. Electrons and protons e. None of these b. Electrons and neutrinos d. Neutrons and protons 7. Chlorine has an atomic number of 17, how many electrons does it have in its outermost (third) shell? a. 7 c. 2 e. 8 b. 4 d Isotopes of the same element differ in the number of: a. Electrons c. Protons e. Electrons and protons b. Protons and neutrons d. Neutrons 9. Radioactive elements usually have an excess number of: a. Electrons c. Protons e. Neutrons b. Protons and neutrons d. Ions 10. What is formed when an atom loses or gains a proton? a. New element c. Ion e. Molecule b. Isotope d. Radioisotope 11. Arsenic has an Atomic Number of 33 and a Mass Number of 75. How many neutrons are in the nucleus of an Arsenic Atom? a. 33 c. 75 e. 108 b. 42 d Consider this chemical equation: HCl H + + Cl -. In this equation, what is HCl? a. Salt c. Acid e. Ion b. Base d. Isotope

2 13. If you Hypoventilate, you could experience which of the following conditions? a. Decreasing CO 2 levels c. Too much oxygen e. Respiratory acidosis b. Basic blood d. Tetany 14. Which of the following is the most abundant sugar in nature? a. Fructose c. Glycogen e. Starch b. Sucrose d. Galactose 15. Which of the following molecules is/are Hydrophilic? a. NaCl c. Triglycerides e. Answers a and c are correct b. Carbohydrates d. Answers a and b are correct 16. The greater the H + concentration, the the ph, the more the solution. a. Higher, acidic c. Lower, acidic e. None of these are correct b. Higher, basic d. Lower, basic 17. Which of the following is your brain's preferred food? a. Glucose c. Fructose e. Triglycerides b. Lactose d. Sucrose 18. A small circular piece of DNA that can be passed from one bacterium to another is called: a. Nucleus c. Nucleoid e. Kinesin b. Plasmid d. Ribosome 19. Which evolved first a. Chloroplasts, then mitochondria b. Mitochondria, then chloroplasts 20. Special endomembranes called detoxify Alcohols in the. a. Lysosomes, liver c. Golgi bodies, liver e. Lysosomes, pancreas b. Peroxisomes, pancreas d. Peroxisomes, liver 21. Prokaryotic cells: a. Have DNA c. Are very small e. All of these are correct b. Are single-celled d. Have ribosomes 22. Life's main energy-carrying molecule is called. Life's main energy-source is. a. Sunlight, ATP c. ATP, sunlight e. Carbon, ATP b. Aerobic respiration, carbon d. Sunlight, DNA 23. In the solute wants to move, in the solution wants to move. a Passive transport, active transport. c. Osmosis, diffusion e. None of the above b. Diffusion, osmosis d. Active transport, passive transport 24. Animals cells are unusual among the Eukaryotic cell type in that they do not have a. DNA c. Cell wall e. Linear chromosomes b. Ribosomes d. RNA 25. In the light reactions of photosynthesis, how does the P700 molecule replace its lost electrons? a. From forming water c. From the P680 molecule e. From light b. By dropping to a lower energy shell d. From NADPH 26. Longer wavelengths of light have more energy than shorter wavelengths of light. a. True b. False 2

3 27. What is the final electron acceptor in the light reactions of photosynthesis? a. ATP c. NADP + e. Cytochrome complex b. H 2 O d. NADPH 28. Movement of a molecule against a concentration gradient is called: a. Simple diffusion c. Osmosis e. Active transport b. Passive transport d. Easy diffusion 29. Does the Cytochrome Complex increase or decrease acidity in the Lumen? a. Increase b. Decrease 30. Which accessory pigment reflects the most yellow light? a. Chlorophyll a c. Beta-carotene b. Chlorophyll b d. Xanthophylls 31. Which of the following is NOT a factor contributing to the H + ion concentration gradient in the lumen during the light reactions of photosynthesis? a. Splitting of H 2 O to restore electrons to P680 releases H + ions into the lumen b. H + ions are used in the stroma to build NADPH c. Cytochrome complex pumps H + ions into the lumen d. P700 pumps H+ ions after receiving electrons e. All of the above are factors. 32. Photosynthetic plants release oxygen into the air. Where does that oxygen come from? a. Carbon dioxide c. C 6 H 12 O 6 e. NADPH b. Water d. NADP + Short answer questions: (2 points each). Answer these questions here in the exam booklet. Note: some questions have more than one part. Make sure you answer all parts. You can get partial credit. Write neatly so I can give you credit! Do not re-write questions in your answers. Short is sweet! 33. Two parts: a. What does the Earth's magnetic field protect the Earth against? Solar/nuclear radiation (not UV) b. What process is increasing the amount of CO 2 in our atmosphere? Burning of fossil Fuels 34. Compare the Earth's early atmosphere with the Earth's atmosphere today. (Don't have to give %). Early: Today: 1. Little free O 2 1. Lots of O 2 2. Lots of CO 2 2. Little CO 2 3. Lots of water vapor 3. Less water vapor 35. What is a polar-covalent bond? A bond between two different atoms where electrons are not shared equally 36. Why can Carbon form four chemical bonds? Because it has 4 vacancies in its outer electron shell (needs 4 more electrons) 3

4 Name Biol 1102 Exam Two parts: a. Neon's atomic number is 10. How many electrons in first shell 2, second shell 8? b. Is Neon stable or does it react with other molecules? Stable 38. Two parts: a. What two things are needed to make Vitamin D? Sunlight and Cholesterol. b. Where is Vitamin D made in our bodies? In our skin 39. Why do our bodies store triglycerides and not sugar? Because fat contains twice as much energy as sugar 40. Two parts: a. Consider Cellulose, Starch, and Glycogen; How are they similar? How are they different? All three are made from glucose chains, but differ in how the glucose molecules are linked together. b. Draw lines matching the word on the left with the correct definition on the right. Cellulose Glycogen Starch How plants store glucose Makes plant cell walls rigid and indigestible How animals store glucose 41. What are proteins made from? Amino Acids 42. What three facts provide evidence that Mitochondria and Chloroplasts were once free-living bacteria? a. Both have their own, DNA, RNA, and Ribosomes b. Both have the bacterial genetic code c. Both have circular DNA like bacteria 43. Fill in the correct words: Photosynthesis is the most important biosynthetic (anabolic) pathway and Cellular respiration is the most important Degradative (catabolic) pathway. 44. Circle the correct answers in the sentence below: (Hydrophobic, Hydrophilic) molecules CAN cross the cell membrane, while (Hydrophobic, Hydrophilic) molecules CANNOT cross the cell membrane. 45. Describe the cell membrane. You can use words, label the diagram, or both. There is a Phospholipid bilayer. The phospholipid molecules are composed of a hydrophilic head that faces outward and two hydrophobic tails that face inward. Hydrophobic tails make it waterproof. 4

5 46. Why is DNA kept inside a nucleus in Eukaryotic cells? To prevent DNA from being damaged by the chemical reactions occurring in the cytoplasm 47. What is Diffusion? Movement of solute molecules from an area of high concentration to an area of low concentration. 48. Give three reasons from class why enzymes are important biological molecules? a. Lower activation energy needed to start chemical reactions b. Make reactions happen very fast c. Most can be reused 49. Write an overview of Photosynthesis (either one from lecture will do). 12H 2 O + 6CO > C 6 H 12 O 6 + 6H 2 O + 6O What are the three things an excited electron can do? a. Drop back down and give off energy as heat b. Drop back down and give off energy as fluorescent light c. Be captured and moved to another molecule. 51. Circle correct answers: In the light reactions of photosynthesis, the Cytochrome Complex uses (active, passive) transport while ATP synthase uses (active, passive) transport. 52. Why do the leaves of deciduous trees turn different colors in Autumn? Accessory pigments become visible as chlorophyll degrades and is not replaced 53. How do pigment molecules absorb light energy (you can use words or draw a picture)? When light energy strikes a pigment molecule, it excites an electron to a higher energy state and moves the electron to the next energy shell. 5