SCIENCE VOCABULARY WORDS  

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1. MECHANICAL DIGESTION – tearing and grinding of teeth on food, as well as churning of food by muscles that line the walls of the digestive tract (makes food smaller)

2. CHEMICAL DIGESTION – breaks down the chemical bonds in nutrients so they can be absorbed into the bloodstream

3. PERISTALSIS – wavelike motion that moves food down through the digestive tract

4. SPHINCTERS – rings of thickened muscles that allow the passage of food from one area of the digestive tract to another area

5. MUCUS – slippery secretion that coats the inner walls of the digestive tract

6. BOLUS – food turns into this moist ball when it is chewed and mixed with saliva

7. SALIVARY AMYLASE – a digestive enzyme that changes starch to simple sugar in the mouth

8. PEPSIN – a digestive enzyme that acts on protein in the stomach

9. CHYME – the stomach contents eventually turn into this thick, uniform liquid

10. CELLULAR RESPIRATION – process by which nutrients are broken down in the presence of oxygen to release energy

11. ABSORPTION – the process by which nutrients pass through the cells that line the digestive tract

12. VILLI – fingerlike projections in the walls of the small intestine to aid in absorption

13. VENTILATION – breathing; process by which air is moved into and out of the lungs

14. DIAPHRAGM – a broad, thin muscle that separates the chest cavity from the abdomen

15. VITAL CAPACITY – amount of air that a person can forcibly exhale after breathing in as much as possible

16. RESIDUAL VOLUME – the air that remains in the lungs even after exhaling as much as possilbe

17. TOTAL LUNG CAPACITY – the sum of the vital capacity and residual volume

18. AEROBIC RESPIRATION – respiration in cells in the presence of oxygen

19. ANAEROBIC RESPIRATION – respiration in cells when there is not enough oxygen available to complete the aerobic phase of cellular respiration

20. CALORIE – amount of heat energy required to raise the temp. of 1 gram of water 1 degree Celsius

21. ENERGY – ability to do work, energy is being used when something is happening

22. ATRIA – top chambers of the heart

23. VENTRICLES – bottom chambers of the heart

24. AORTA – the major artery of the body

25. ARTERY – blood vessel that moves blood away from the heart

26. VEIN – blood vessel that moves blood toward the heart

27. PULSE – rhythmic expansion and contraction of an artery

28. BLOOD PRESSURE – the force exerted by the blood on the walls of the arteries

29. CARTILAGE – slippery tissue found at the ends of bones at joints; reduces friction

30. JOINTS – where bones meet

31. NERVES – carry impulses that stimulate muscles to contract

32. TENDONS – connect muscles to bones

33. LIGAMENTS – connect bones to bones at joints

34. PLANE JOINT – found where bones are flat; allow slipping or gliding movements; small bones in the wrist and ankles are examples

35. BALL AND SOCKET JOINT – found at shoulders and hips; allows movement in all directions

36. HINGE JOINT – moves back and forth like a door; elbow is a hinge joint

37. PIVOT JOINT – allow limited rotation of one bone against another, like where the neck joins the head and where the radius and ulna meet just below the elbow

38. SADDLE JOINT – occur where the thumb meets the palm; each bone has both convex and concave surfaces that join, like a person sitting on a saddle

39. SMOOTH MUSCLE – line the digestive tract and are responsible for peristalsis; involuntary muscles

40. CARDIAC MUSCLE – heart muscle; involuntary muscle

41. SKELETAL MUSCLE – voluntary, except through a reflex action; responsible for moving your body around

42. EARTH CENTERED – the perspective that the earth is the center of the solar system

43. SUN -CENTERED – the perspective that the sun is the center of the solar system

44. GALAXY – large system of dust, gas, stars, and other bodies that has a particular shape

45. ASTRONOMICAL UNIT – a unit of measure equal to the average distance between earth and sun, about 150 million kilometers (about 93 million miles)

46. ROTATION – the movement of an object as it spins around a central axis

47. REVOLUTION – the movement of an object around a central object (the earth revolves around the sun in 365 days)

48. AXIS – an imaginary line that runs through the middle of an object (from pole to pole) around which that object rotates

49. SOLAR NOON – time of day when the sun reaches its highest point

50. HORIZON – the plane that extends from one’s eye to the edge of Earth

51. DEGREE – unit for measuring angles and arcs; one degree equals 1/360 of a circle

52. ECLIPTIC – path of the sun, planets, and moon in the sky as seen from earth; the plane along which these orbit

53. PHASES – any of 8 various stages in which the Moon appears to change its shape

54. SIDEREAL MONTH – time it takes the moon to orbit earth one complete revolution (about 27.3 days)

55. SYNODIC MONTH – time it takes between successive repetitions of the same lunar phase (example: the time from one new moon to the next new moon); about 29.5 days long

56. WAXING – the illuminated portion of the moon is continually growing

57. WANING – the illuminated portion of the moon is shrinking

58. UMBRA – the inner, darker part of a shadow

59. PENUMBRA – the lighter, outer part of a shadow cone

60. LUNAR ECLIPSE – the blocking of sunlight to the Moon; occurs during a full moon, when Earth’s shadow lands on the moon

61. SOLAR ECLIPSE – the blocking of the Sun’s light that occurs during a new moon when the moon’s shadow falls on earth

62. SYGZY – for a solar or lunar eclipse to occur, the sun, earth, and moon must be in sygzy (in a straight line)

63. SOLAR ENERGY – energy from the sun

64. RADIATION – process by which energy is transferred from one object (Sun) to another (planet) without the space between them being heated

65. SUNSPOT – relatively darker, cooler area on the Sun’s surface that emits charged particles

66. SOLAR FLARE – a sudden brightness near a sunspot; explosion of gas from the Sun’s surface

67. TERRESTRIAL PLANETS – the name given to the 4 inner planets (Mercury, Venus, Earth, Mars); terrestrial means having to do with solid rock

68. GASEOUS PLANETS – the name given to the 4 outer planets (Jupiter, Saturn, Uranus, Neptune); planets that are composed of compounds that under normal Earth conditions would be gases

69. ASTEROIDS – small, rocky solar system object that orbits independently around the sun in the asteroid belt

70. CRATERS – bowl-shaped pit on a planet, moon, or asteroid formed by the impact of an object or by volcanoes

71. IMPACT CRATERS – caused by asteroids, comets, or meteoroids striking the surface of planets, moons, or asteroids

72. VOLCANIC CRATERS – caused when a material from within the volcano blasted a hole in the top of its summit

73. WEATHERING – all the processes that cause rocks to fragment, crack, crumble, or decay

74. EROSION – process by which the earth is broken down and moved from place to place by wind and water

75. LANDSLIDES – occur when masses of rock or debris move down a slope

76. REGOLITH – loose material that makes up the surface of a planet or moon

77. HUMUS – the organic remains of decomposed vegetation

78. TECTONICS – the forces or conditions within a planet or moon that cause movements in the crust and/or compression of the crust

79. GRAVITY – a force of natural attraction between 2 objects; strength of the force is due to the mass and distance between the 2 objects

80. MASS – total amount of matter in an object; not dependent on gravitational pull

81. WEIGHT – a measure of the force of gravity on an object

82. ORBITAL VELOCITY – the speed at which a planet travels in its orbit

83. ORBITAL PERIOD – the time that it takes an object to orbit another object one complete time (also called period of revolution)

84. LAW OF INERTIA – states that a body in motion tends to travel in a straight line unless an outside force disturbs it

85. ACCELERATION – changing of the direction of motion

86. TIDES – periodic rising and falling of the surface level of an ocean resulting from the gravitational attraction of the moon and the sun on the solid and liquid surfaces of Earth

87. COMET – mass of frozen gas, cosmic dust, ice crystals, and organic material whose orbit around the sun takes it outside of the solar system

88. NUCLEUS – main part of a comet

89. COMA – part of the comet that surrounds the nucleus

90. HEAD – the coma and the nucleus together

91. TAIL – gas and dust that stream away from the comet

92. METEOROID – a solid object moving between planets, different from asteroids and planets because it’s smaller

93. METEOR – meteoroid that burns up in Earth’s atmosphere

94. METEORITE – meteoroid that does not completely burn up in Earth’s atmosphere and strikes Earth

95.   FOSSILS – the preserved remains or impressions of organisms or Earth’s geological past`