LECTURE EXAM 1 REVIEW

1. What is a monosaccharide?

Answer: The simplest carbohydrate; a single sugar molecule (e.g., glucose, fructose, galactose).

2. What are the functions of monosaccharides?

Answer: Provide immediate energy and serve as building blocks for larger carbohydrates.

3. What is a disaccharide?

Answer: A carbohydrate made of two monosaccharides joined by a glycosidic bond.

4. Examples of disaccharides?

Answer: Sucrose, lactose, maltose.

5. Define atom, element, compound, molecule, and isotope.

Answer:

  • Atom: Smallest unit of matter

  • Element: Substance made of one type of atom

  • Compound: Two or more different elements chemically combined

  • Molecule: Two or more atoms bonded together

  • Isotope: Atoms of the same element with different numbers of neutrons

6. What is pH?

Answer: A measure of hydrogen ion concentration; indicates acidity or alkalinity.

7. What are the different types of fats?

Answer:

  • Saturated fats: No double bonds

  • Unsaturated fats: One or more double bonds

  • Trans fats: Artificially hydrogenated fats

8. How many covalent bonds can an atom form?

Answer: Determined by valence electrons. Example:

  • Carbon = 4 bonds

  • Oxygen = 2 bonds

  • Nitrogen = 3 bonds

  • Hydrogen = 1 bond

9. What pH is considered acidic?

Answer: Less than 7.

10. What pH is considered basic (alkaline)?

Answer: Greater than 7.

11. What easily crosses the cell membrane?

Answer: Small nonpolar molecules such as oxygen and carbon dioxide.

12. What cannot easily cross the cell membrane?

Answer: Large molecules, ions, and polar molecules.

13. What is a channel protein?

Answer: A membrane protein that provides a passageway for substances.

14. What is a carrier protein?

Answer: A membrane protein that changes shape to move substances across the membrane.

15. What is diffusion?

Answer: Movement of molecules from high concentration to low concentration.

16. What is osmosis?

Answer: Diffusion of water across a selectively permeable membrane.

17. Know the major organelles.

Answer:

  • Nucleus = control center

  • Ribosomes = protein synthesis

  • ER = transport/synthesis

  • Golgi = packaging

  • Lysosomes = digestion

  • Mitochondria = ATP production

18. What are microfilaments?

Answer: Thin cytoskeletal fibers made of actin.

19. What are intermediate filaments?

Answer: Fibers that provide structural support.

20. What are microtubules?

Answer: Hollow tubes involved in shape, transport, cilia, and flagella.

21. What are DNA nucleotides made of?

Answer: Phosphate group, deoxyribose sugar, and nitrogenous base.

22. What is a hypotonic solution?

Answer: Lower solute concentration outside the cell.

23. What happens to animal cells in a hypotonic solution?

Answer: They swell and may burst.

24. What is a hypertonic solution?

Answer: Higher solute concentration outside the cell.

25. What happens to plant cells in hypotonic and hypertonic solutions?

Answer:

  • Hypotonic = turgid

  • Hypertonic = plasmolyzed

26. How do cilia and flagella move?

Answer: Using microtubules arranged in a 9+2 pattern.

27. Cytosol vs. cytoplasm?

Answer:

  • Cytosol = intracellular fluid

  • Cytoplasm = cytosol + organelles

28. What dissolves in water?

Answer: Polar and ionic substances.

29. Why can an element form covalent bonds?

Answer: To fill its outer electron shell.

30. What is the extracellular matrix in animal cells made of?

Answer: Glycoproteins, collagen fibers, and proteoglycans.

31. How is membrane fluidity maintained?

Answer: Cholesterol helps regulate membrane fluidity.

32. What is active transport?

Answer: Movement against the concentration gradient using ATP.

33. What are major polysaccharides?

Answer: Starch, glycogen, cellulose, chitin.

34. Which organelle produces ATP?

Answer: Mitochondria.

35. Why is ice less dense than liquid water?

Answer: Hydrogen bonds create an open crystal structure.

36. Why is water polar?

Answer: Oxygen attracts electrons more strongly than hydrogen.

37. Cohesion vs. adhesion?

Answer:

  • Cohesion = water sticks to water

  • Adhesion = water sticks to other substances

38. What is mass number?

Answer: Protons + neutrons.

39. What are the monomers of major polymers?

Answer:

  • Proteins → amino acids

  • Carbohydrates → monosaccharides

  • Nucleic acids → nucleotides

  • Lipids (not polymers) → glycerol + fatty acids

40. What is starch?

Answer: Plant energy-storage polysaccharide.

41. What is glycogen?

Answer: Animal energy-storage polysaccharide.

42. What linkage joins monosaccharides?

Answer: Glycosidic linkage.

43. What linkage is found in lipids?

Answer: Ester linkage.

44. What is endocytosis?

Answer: Cell takes material in using vesicles.

45. What is a covalent bond?

Answer: Sharing of electrons.

46. What is an ionic bond?

Answer: Transfer of electrons causing attraction between ions.

47. What is a hydrogen bond?

Answer: Weak attraction involving hydrogen and electronegative atoms.

48. What is an isotope?

Answer: Same number of protons, different number of neutrons.

49. Difference between single, double, and triple covalent bonds?

Answer:

  • Single = 1 shared pair

  • Double = 2 shared pairs

  • Triple = 3 shared pairs

50. Why do oceans become more acidic?

Answer: CO₂ dissolves in water forming carbonic acid.

51. What is a buffer?

Answer: Substance that resists changes in pH.

52. Why is carbon the backbone of organic compounds?

Answer: Carbon forms four stable covalent bonds.

53. Phagocytosis vs. autophagy?

Answer:

  • Phagocytosis = engulfing external material

  • Autophagy = recycling damaged cell components

54. What is Tay-Sachs disease?

Answer: Lysosomal storage disease caused by inability to break down GM2 gangliosides.

55. What organelle is involved in Tay-Sachs disease?

Answer: Lysosome.

56. What are the major organ systems?

Answer: Integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, reproductive.

57. Which organelle packages proteins?

Answer: Golgi apparatus.

58. What are DNA complementary base pairs?

Answer:

  • A pairs with T

  • C pairs with G

59. Levels of organization?

Answer: Atom → Molecule → Organelle → Cell → Tissue → Organ → Organ System → Organism.

60. What are characteristics of life?

Answer: Organization, metabolism, responsiveness, growth, development, reproduction, homeostasis.

61. What is a serous membrane?

Answer: Membrane lining body cavities and covering organs.

62. What are the major body cavities?

Answer: Cranial, vertebral, thoracic, abdominal, pelvic.

63. What is the anatomical position?

Answer: Standing upright, palms forward, feet forward.

64. What is the supine position?

Answer: Lying face up.

65. What is the prone position?

Answer: Lying face down.

66. What is the sagittal plane?

Answer: Divides left and right.

67. What is the frontal (coronal) plane?

Answer: Divides front and back.

68. Superior vs. inferior?

Answer:

  • Superior = above

  • Inferior = below

69. Medial vs. lateral?

Answer:

  • Medial = toward midline

  • Lateral = away from midline

70. What cavity contains the lungs?

Answer: Pleural cavities.

71. What cavity contains the heart?

Answer: Pericardial cavity.

72. Most common elements in living organisms?

Answer: Oxygen, carbon, hydrogen, nitrogen.

73. Why is the membrane a phospholipid bilayer?

Answer: Hydrophilic heads face water; hydrophobic tails face inward.

74. What is a trace element?

Answer: Element required in very small amounts (e.g., iron, iodine).

75. Which organelle contains digestive enzymes?

Answer: Lysosome.