Ponce de Leon 8thGrade Winter Science Package '13-'14

Transcription

1 Name: Teacher: Period: Date: Ponce de Leon 8thGrade Winter Science Package '13-'14 Multiple Choice: Identify the choice that best completes the statement or answers the question. 1. Which of these phrases best describes the general properties of metals? a. highly reactive b. malleable, ductile, good conductors c. not easily corroded d. dull and brittle 2. Which parts of the atom move around the nucleus? a. atomic mass units b. electrons c. protons d. neutrons 3. Carbon dioxide is an example of a(n) a. compound. b. nucleic acid. c. sugar. d. element. 4. Specialized cells are found only in a. animals. b. single-celled organisms. c. bacteria. d. many-celled organisms. 5. Which of the following statements is part of the cell theory? a. Only plants are composed of cells. b. All cells are produced from other cells. c. Cells can be produced from nonliving matter. d. Cells are one of several basic units of structure and function in living things. 6. Many substances move through cell membranes from areas of higher concentration to areas of lower concentration in the process of a. cellular respiration. b. diffusion. c. reproduction. d. DNA replication. 7. Which of the following best describes the function of mitochondria? a. They convert energy from food molecules into energy the cell can use. b. They store energy from food molecules. c. They store energy from sunlight. d. They produce nucleic acids that release energy. 8. What is copied during replication? a. the cell s organelles b. chromosomes c. the cell s DNA d. two daughter cells 9. Which of these is not a function of cell division? a. growth b. respiration c. repair d. reproduction 10. What happens when chemical bonds break and new bonds form? a. a physical change b. a chemical change

2 c. matter is destroyed d. surface area increases 11. The only sure evidence for a chemical reaction is a. the formation of a gas. b. a color change. c. the production of one or more new substances. d. changes in properties. 12. When a chemical reaction takes place in an open system, a. matter can enter from or escape to the surroundings. b. matter is not allowed to enter from or escape to the surroundings. c. matter can enter from the surroundings, but cannot escape to the surroundings. d. matter cannot move at all. 13. The part of the earth that consists of water in the form of ice that is on or inside Earth is called the a. biosphere. b. cryosphere. c. geosphere. d. hydrosphere. 14. Climates are classified according to two major factors: a. elevation and precipitation. b. latitude and temperature. c. elevation and latitude. d. precipitation and temperature. 15. The layers of the atmosphere are classified according to changes in a. altitude. b. density. c. pressure. d. temperature. 16. When the north end of Earth s axis is tilted toward the sun, North America will experience a. more indirect rays and shorter days. b. more indirect rays and longer days. c. more direct rays and shorter days. d. more direct rays and longer days. 17. A measure of the average kinetic energy of the individual particles in an object is called a. thermal energy. b. conduction. c. convection. d. temperature. 18. The transfer of energy by electromagnetic waves is called a. conduction. b. convection. c. radiation. d. insulation. 19. In organisms, cells obtain energy by breaking bonds. Breaking bonds releases a. nuclear energy. b. electrical energy. c. electromagnetic energy. d. chemical energy. 20. Clara placed an empty mug on the table and poured hot tea into the mug. When she went to pick up the mug it was too hot to hold. Which type of heat transfer occurred between the tea and the mug? a. conduction b. convection c. radiation d. freezing 21. Which of the following actions does no work?

3 a. lifting a baseball b. holding a baseball c. throwing a baseball d. dropping a baseball 22. Which of the following has kinetic energy? a. a rock poised for a fall b. an archer s bow that is drawn back c. a rolling bowling ball d. a car waiting at a red light 23. Potential energy that depends on height is called a. kinetic energy. b. gravitational potential energy. c. elastic potential energy. d. mechanical energy. 24. How would you calculate an object s mechanical energy? a. Add its kinetic and potential energies. b. Multiply its kinetic and potential energies. c. Subtract its kinetic energy from its potential energy. d. Subtract its potential energy from its kinetic energy. 25. When an object s position relative to another object is changing, a. it is in motion. b. it is speeding. c. it has a high velocity. d. it is accelerating. 26. The rate at which velocity changes is called a. instantaneous speed. b. direction. c. acceleration. d. motion. 27. Which of the following captures energy from sunlight during photosynthesis? a. solar cells b. pigments c. chlorophyll d. oxygen 28. The force of gravity on a person or object on the surface of a planet is called a. mass. b. terminal velocity. c. weight. d. free fall. 29. What happens when two forces act in the same direction? a. They cancel each other out. b. The stronger one prevails. c. Their strengths are added. d. Their sum divided by two is the total force. 30. According to Newton s third law of motion, when a hammer strikes and exerts force on a nail, the nail a. creates a friction with the hammer. b. disappears into the wood. c. exerts an equal and opposite force on the hammer. d. moves at a constant speed. 31. What does the notation TT mean to geneticists? a. two dominant alleles b. heterozygous alleles c. at least one dominant allele d. one dominant and one recessive allele

4 32. If a homozygous black guinea pig (BB) is crossed with a homozygous white guinea pig (bb), what is the probability that an offspring will have black fur? a. 25 percent b. 50 percent c. 75 percent d. 100 percent 33. A heterozygous organism has a. three different alleles for a trait. b. two identical alleles for a trait. c. only one allele for a trait. d. two different alleles for a trait. 34. Table salt and water are examples of a. atoms. b. elements. c. mixtures. d. substances. 35. The surface of water can act like a sort of skin due to a property of liquids called a. viscosity. b. surface tension. c. condensation. d. evaporation. 36. Which of the following describes a physical change that results from the addition of thermal energy? a. inflating a balloon b. tearing paper c. a melting ice cube d. condensation on a mirror 37. In cold climates, the amount of snow on the ground may decrease even if the temperature stays below zero degrees Celsius. The process that best explains this event is a. condensation. b. sublimation. c. melting. d. evaporation. 38. During the process of sublimation, a. a solid turns directly into a gas. b. a solid turns into a liquid. c. a gas turns directly into a solid. d. a liquid turns into a gas. 39. Farmers may leave fields unplanted or plant alternate crops to reduce a. nutrient depletion. b. desertification. c. strip mining. d. erosion. 40. One of the acids in acid rain forms when water combines with a. ozone. b. particles. c. hydrogen gas. d. sulfur oxides. 41. A liquid mixture in which particles can be seen and easily separated by settling or filtration is a a. solution. b. suspension. c. solvent. d. solute. 42. When a solid compound dissolves in water, a. it breaks up into individual crystals. b. it always conducts electricity.

5 c. its particles surround individual water molecules. d. each of its particles becomes surrounded by water molecules. 43. How would a solute affect the boiling point of water? a. The water will boil at a lower temperature. b. The water will boil at a higher temperature. c. The water will not boil. d. The boiling point will be the same as the freezing point. 44. Observations that deal with a number or amount are called a. manipulated observations. b. quantitative observations. c. qualitative observations. d. operational observations. 45. When you make a possible explanation for a set of observations you are formulating a a. theory. b. law. c. prediction. d. hypothesis. 46. The volume of an irregular object can be measured by a. multiplying the object s length, width, and height. b. multiplying the object s density by its mass. c. submerging the object in water in a graduated cylinder. d. placing the object on a triple-beam balance. 47. The density of a block of wood with a volume of 50 cubic centimeters and a mass of 100 grams is a. 2 g/cm 3 b. 0.5 g/cm 3 c. 500 g/cm 3 d. 5,000 g/cm Electromagnetic waves can transfer energy without a(n) a. medium. b. electric field. c. magnetic field. d. change in either a magnetic or an electric field. 49. What happens when parallel rays of light hit a smooth surface? a. diffuse reflection b. diffraction c. refraction d. regular reflection 50. In which medium does sound travel the fastest? a. steel b. air c. water d. The speed is the same in all three mediums.

6