Across
- 3. The process in which a solid changes into a liquid when heated.
- 7. A recurring sequence of events, often in nature.
- 8. A substance that releases hydrogen ions when dissolved in water.
- 10. The phenomenon by which materials exert attractive or repulsive forces on each other.
- 12. The smallest type of blood vessel that connects arteries and veins.
- 17. A layer in the atmosphere that protects Earth from harmful ultraviolet radiation.
- 18. A state of matter that has neither a definite shape nor a definite volume.
- 20. The basic building blocks of matter.
- 23. The fusion of male and female gametes to form a zygote.
- 27. A type of bond formed when atoms share electrons.
- 29. Clues:
- 31. A process in which one or more substances are changed into others.
- 32. A form of energy that travels through air as a vibration of particles.
- 33. A species that is at risk of becoming extinct.
- 34. A measure of how acidic a solution is, typically measured on the pH scale.
- 37. The process by which water moves through the soil and into the roots of plants.
- 38. The flow of electric charge in conductors.
- 39. The branch of biology that deals with the study of ecosystems and organisms' interactions with their environment.
- 40. Related to the moon.
- 43. A classification based on biological differences and roles in reproduction.
- 44. A microscopic infectious agent that can only reproduce within the living cells of a host organism.
- 47. The process by which a gas changes into a liquid.
- 50. A substance that dissolves a solute to form a solution.
- 51. The process by which plants make their own food using sunlight.
- 53. The units of heredity that carry information for traits in organisms.
- 54. The element in the atmosphere that makes up about 78% of it.
- 58. Compounds that contain carbon, typically from living organisms.
- 59. The ability to maintain ecological balance and avoid depletion of resources.
- 61. The process by which organisms convert food into energy with the help of oxygen.
Down
- 1. An object that produces a magnetic field and attracts certain materials like iron.
- 2. The fine powder released by flowers that contains the male gametes in plants.
- 4. The process by which traits are passed from parents to offspring.
- 5. The process by which liquid turns into gas.
- 6. Subatomic particles that have no charge and are found in the nucleus of an atom.
- 9. The process by which insects and amphibians change their body form during their life cycle.
- 11. A compound of nitrogen and hydrogen commonly used in fertilizers.
- 13. The process by which plants make their own food using sunlight.
- 14. The introduction of harmful substances into the environment.
- 15. A state of matter with a definite shape and volume.
- 16. A substance used to stimulate the production of antibodies to protect against diseases.
- 19. The system that is responsible for the transport of blood, nutrients, and gases in the body.
- 21. The scientific study of animals and their biology.
- 22. An instrument used to measure temperature.
- 24. A pH of 7, indicating neither acidity nor alkalinity.
- 25. A phenomenon by which materials exert attractive or repulsive forces on each other.
- 26. The force that attracts objects towards the center of the Earth.
- 28. A substance that releases hydrogen ions when dissolved in water.
- 30. The transfer of heat through a material without the movement of the material itself.
- 35. A material that allows the flow of electric current.
- 36. The fluid in the circulatory system that carries oxygen and nutrients to the body.
- 41. A pure substance that cannot be broken down into simpler substances by chemical means.
- 42. The green pigment in plants that is involved in photosynthesis.
- 45. A material that does not allow the flow of electricity.
- 46. The process by which two atoms combine to form a heavier atom, releasing energy.
- 48. The degree of hotness or coldness of an object, typically measured with a thermometer.
- 49. The branch of science that deals with the composition, structure, and properties of matter.
- 52. The reproductive body of a plant that contains an embryo.
- 55. The branch of science that deals with celestial objects, space, and the universe.
- 56. Refers to a system based on two digits, often 0 and 1, in computing.
- 57. The movement of molecules from an area of higher concentration to an area of lower concentration.
- 60. The preserved remains or traces of organisms from past geological ages.