Science TAKS Facts

1. Science TAKS Facts

2. Levels of Organization largest smallest smallest largest

3. Human Body Systems

4. PLANT Cell wall Contains chloroplast Larger vacuoles ANIMAL Flagellum to help with movement CELLS

5. Cell Parts • CELL MEMBRANE – the outer boundary that only allows certain materials to move into or out of the cell • CYTOPLASM – gel-like material that contains water and nutrients • NUCLEUS – contains the chromosomes with the DNA • MITOCHONDRIA – breaks down food and releases energy • VACUOLES – storage areas for cells

6. SUCCESSION • Primary – no soil; lichens are a pioneer species that help develop soil • Secondary – occurs after devastation (Fire, flood)

7. CHARLES DARWIN • NATURAL SELECTION • ADAPTATION • VARIATION • EVOLUTION • SPECIES Galapagos Island: Large turtles Variety of Finches, adaptation to Different environments

8. Species and Adaptations • SPECIES – group of similar organisms that can mate and produce fertile offspring • ADAPTATIONS – genetic trait that helps an organism survive and reproduce • EVOLUTION – change in a species over time • NATURAL SELECTION – process by which individuals better adapted to their environment are more likely to survive and reproduce

9. ECOSYSTEMS (BIOMES)

10. FOOD WEBS • Arrows show movement of energy through the system • Food chain always begins with producer • Energy originates with sun as part of photosynthesis

11. FOOD PYRAMID 10% of the available energy moves up to the next level producers Decomposers

12. Symbiotic relationships • Mutualism- both benefit • Commensalism- neither is affected nor harmed not commonly seen in nature • Parasitism- one benefits and the other is harmed • Ex. Flea and dog

13. PUNNETT SQUARE Dominant allele Recessive allele Homozygous dominant Heterozygous Homozygous recessive 75% display dominant trait 25% display recessive trait

14. GENOTYPE – Genetic description • TT, Tt, tt • PHENOTYPE – Physical description • tall, tall, short

15. PHOTOSYNTHESIS • CO2 + H2O + sunlight  C6H12O6 + O2 • Carbon dioxide + water + sunlight  glucose + oxygen

16. Feedback Mechanisms that maintain homeostasis • Maintaining body temperature • Maintaining blood sugar levels glucose levels controlled with insulin and diet Tugor pressure-plants

17. Objecive 3 Structure and Properties of Matter

18. STATES OF MATTER

21. ATOMIC STRUCTURE • Valence electrons – electrons on the last energy level of an atom

22. ELEMENT INFORMATION

23. PERIODIC TABLE Noble gases Group – columns - elements have similar properties Period – rows - # of energy levels in an atom

24. CHEMICAL REACTIONS

25. ATOM VS. MOLECULE

26. COUNTING ATOMS • Subscript – number below letters; tells # of atoms • Coefficient – Number in front of element or compound; tells number of units; multiplied by scubscript

27. Law of Conservation of Mass • Mass of reactants and mass of products will remain the same You cannot create nor can you destroy matter; you can only rearrange it!

28. PHYSICAL CHANGES • Does not change the composition of the substance • Examples: change in shape, size, phase (melting, freezing, condensing, evaporating)

29. Physical Properties • Porosity • Hardness • Conductivity • Solubility • Density • Viscosity • luster

30. Chemical Properties • Reactivity • Corrosiveness • Flammability • oxidation

31. CHEMICAL CHANGES • New substance is formed; the change cannot be undone • CLUES: when 2 substances are mixed and • Bubbles form – created a gas • Color changes – created a solid • Temperature changes • Odor is produced

32. SPECIFIC HEAT • HIGH SPECIFIC HEAT • Takes more energy to change temperature • Slower temperature change • Example: water, nonmetals • LOW SPECIFIC HEAT • Takes less energy to change temperature • Quicker temperature change • Example: sand, metals

33. Endothermic Reaction • Energy absorbed into the system Ex. Photosynthesis, cold pack

34. Exothermic Reaction • Energy is released from the system Ex. Candle burning, cellular respiration

35. Objective 4 Forces, Motion, and Energy

36. FORCES • Push or pull • Balanced forces • Have no effect on an object’s motion • Opposite in direction and equal in strength • Unbalanced forces – • Motion is in the direction of the stronger force. • Opposite in direction and unequal in strength

37. 1st LAW OF MOTION • Known as the LAW OF INTERTIA • Forces are balanced

38. 2nd LAW OF MOTION

39. 3rd LAW OF MOTION • For every action force, there is an equal and opposite reaction force • Forces are balanced • Motion is determined by mass of objects involved

40. ENERGY • Ability to work or cause change • FORMS OF ENERGY: electrical, mechanical, chemical, thermal, potential, kinetic • LAW OF CONSERVATION OF ENERGY – cannot create nor destroy energy; energy may be transformed

41. decreasing height means decreasing potential energy Increased height means Increased potential energy increasing speed means Increasing kinetic energy Decreasing speed means Decreasing kinetic energy

42. ENERGY TRANSFORMATIONS

43. SOURCES OF ENERGY • Renewable – readily available • Wind, water, solar • Nonrenewable – takes a long time to replenish • Fossil fuels

44. TRANSVERSE WAVE • PARTICLES MOVE UP AND DOWN • EXAMPLE: LIGHT WAVES, RADIO WAVES, MICROWAVES

45. ELECTROMAGNETIC SPECTRUM

47. REFLECTION • Light bounces off of a surface and starts traveling in a different direction • Example: image in a mirror, echo

48. REFRACTION • Change in the direction of a wave as it passes from one medium to another; causes the wave to bend • Changes the speed and wavelength

49. DIFFRACTION • Wave direction changes as it passes through an opening • Will cause a straight wave front to bend

50. LEVERS BEST WHEN FULCRUM IS NEAR RESISTANCE FORCE BEST WHEN RESISTANCE FORCE IS NEAR FULCRUM NOT AN ADVANTAGE FOR FORCE; ADVANTAGE IS IN DISTANCE GAINED