Grade 8 Science Cheat Sheet

1. Gravity is a law.
2. The strength of gravity is determined by f=m*a
3. Newton­'s second law is the Law of the Transfer of Energy.
4. The theory of Pangea is about how the continents were all together but moved apart over time.

5. Atoms make up everyt­­hing.
6. Atoms are made up of neutrons, protrons, and electrons.
7. Protrons and Neutrons are inside of the nucleus.
8. Electrons orbit around the nucleus at incredible speeds.
9. Molecules are made up atoms.
10. Atoms are also known as elements.
11. A compound is two or more diff­erent elements put together.

21. You are made of millions of cells each with a different function.
22. Your cells are constantly dying and reprod­ucing all the time.
23. Mitosis is when a cell splits into two identical copies.
24. A cell spends most of it's life in Interp­hase.
25. The phases of mitosis are prophase, metaphase, anaphase, and telophase.
26. Nerve cells hardly reproduce.
27. If a cell has chromatin, it is in Interp­hase.

46. Biotec­hnology is involved in pharma­ceu­ticals because it helps create medicines.
47. Biotec­hnology is involved in farming because it can help there be less pesticide use on crops and also it helps crops last in the cold.
48. Biotec­hnology is involved in police because it helps in forensics finding who a person is or matching DNA found at a crime scene.
49. Biotec­hnology is involved in zoology because it can help preserve endangered animals.
50. Biotec­hnology is involved in antibi­ote­rrorism because it can create a protein that will counteract the virus used.

70. John Dalton was the the first person to devlope the theory of the atom, a postively charged sphere.
71. J.J. Thompson built on the ideas of John Dalton and said that the atom was a positively charged shere with negatively charged particle evenly distri­buted throug­hout.
72. Ernest Rutherford built on the ideas of J.J. Thompson and said that the in the center of the atom is the necleus filled with protrons and neutrons and surrounded by electrons.

28. Organelles are specia­lized structures in a cell.
29. Endopl­asmic reticulum is the organelle that ships out proteins.
30. Ribosomes are the organelles that make proteins.
31. Amoebas are single celled organisms that uses pseudopods to move and catch food.
32. Paramecium are single celled organisms that are covered in cilia which helps them move.
33. Euglenas are single celled organisms that uses a flagellum to move and stun prey.
34. Volvox are single celled organisms that form colonies and use flagellum to move.

51. A chemical equation is balanced when both sides of the equation have the same amount of each element that went into the equation.
52. The law of conser­vation of mass states that mass can neither be created nor destroyed.

73. Meiosis is a type of cell division in which a necleus divides into four daughter nuclei each containing half the chromosome number of the parent necleus.
73. Meiosis consists of 8 phases, prophase 1, metaphase 1, anaphase 1 telophase 1, prophase 2, metaphase 2, anaphase 2, and telophase 2.
74. In prophase 1 homologous chromo­somes pair up and exchange fragments.
75. In metaphase 1 the chromasome pairs line up at the equator and attach to spindle fibers.
76. In anaphase 1 the spindle fibers pull the chromosome pairs apart.
77. In telophase 1 the spindle fibers pull the chromosome pairs into their own cells and form a necleus.
78. In prophase 2 both cells' homologous chromo­somes pair up and exchange fragments.
79. In metaphase 2 both cells' chromo­somes line up at the equator and have spindle fibers attach to them.
80. In anaphase 2 the spindle fibers in both cells pull the chromo­somes apart.
81. In telophase 2 the spindle fibers have pulled the chromo­somes apart and caused them to start forming their own necleus.

12. The periodic table has elements organized by the number of protrons each element has.
13. The number of protrons, neutrons, and electrons changes for each element.
14. Compounds can't be separated physic­ally.
15. Mixtures are 2 or more compound together.

35. Osmosis is when a liquid moves from an area of low concen­tration to an area of high concen­tra­tion.
36. Endocy­tosis is when a cell takes in matter and forms a vacuole.
37. Exocytosis is when a cell removes matter using a vacuole.
38. Photos­ynt­hesis is the process that plant cells use to make food.
39. Respir­ation is when a cell produces energy by taking oxygen and breaths out carbon dioxide.
40. Fission is when a cell divides into two.

53. Leukemia is a disease that occurs when your body produces too many white blood cells.
54. Diabetes is a condition that occurs when your body can't process glucose normally.
55. Tuberc­ulosis is a disease charac­terized by the growth of tubercules in the lungs.
56. Influenza is a highly contagious viral infection of the respir­atory passages that is also know as the flu.
57. Strep throat is an infection in throat that comes with a fever.
58. Dysentery is an infection of the intestine resulting in diarrhea.
59. Tetanus is a bacterial infection that causes spasms of the voluntary muscles.
60. A STD is an infectious disease that is spread from person to person by sexual contact.
61. HIV is also known as human immuno­def­iciency virus, a virus that weakens the body's immune system, leading to life-t­hre­atening infect­ions; causes AIDS.
62. AIDS is also known as acquired immuno­def­iciency syndrome, a disease that causes lowered a immune system, leading to a higher chance of getting sick.
63. Malaria is a disease that causes a fever and invades blood cells. Carried by mosqui­toes.

82. There are 10 types of elements, alkali metals, alkaline earth, transition metals, basic metals, semime­tals, nonmetals, halogens, noble gases, lantha­nides, and actinides.
83. There are 103 elements on the periodic table.
84. There are 3 categories of elements metals, metall­oids, and gases.
85. Hydrogen is the only gas on the left hand side of the periodic table.
86 You determine the atomic mass of a single atom of an element by adding up the mass of the protrons and neutrons.
87. The periodic table is arranged in periods or rows and they go from left to right. Each element in a period has the same energy levels.
88. The periodic table is also arranged in families or groups that go form top to bottom. Each element in a family has the same charac­ter­istics.
89. The charac­ter­istics of an element are also known as chemical properties which are things that allow a chemical change to occur.
90. Dmitri Mendeleev is the man that made the periodic table.

16. Chemical changes are also known as chemical reactions.
17. Chemical changes are different from physical changes because in a chemical change you can't get what was used in the reaction back but in a physical change, such as crumpling up a piece of paper, you can uncrumple the paper.
18. Chemical changes are charac­terized by the forming of a precip­itate, a substance formed by a solution.
19. A solution is a liquid mixture where a solute (the substance dissolved) is distri­buted evenly in the solvent (the substance that dissolved the solute).
20. Physical changes involve tearing or crumpling an object but while mainta­ining its original traits. Chemical changes involve changing the object through the use of chemicals.

41. Biotec­hnology is the use of natural processes to create something.
42. Biotec­hnology is used in making better crops.
43. Biotec­hnology can also be used for making medicine.
44. Two biotec­hnology centers in North Carolina are located in Sanford, North Carolina and Research Triangle Park, North Carolina.
45. Biotec­hnology is also being used in the treatment of cancer.

64. Protrons are positively charged particles in the necleus of an atom.
65. Neutrons are particles with neutral charge in the necleus of an atom.
66. Electrons are negatively charged particles in the necleus of an atom.
67. A solution is a mixture of a solute and solvent.
68. A substance is made of more thanone element that combine to form something new, made from a chemical reaction.
69. A chemical reaction is a chemical reaction and when a new substance is made, bonds break and recombine to form something new.