Parts of an experiment

1. Parts of an experiment

2. constant • Something in an experiment that is kept the same in all trials. • Egg-speriment: • Egg, amount of solution (200 mL), cup, • Covering with plastic wrap, scale, temperature, time of day when we checked the egg

3. control • The standard for comparison in an experiment. • You don’t administer the independent variable to it.

4. variable • a variable is any factor that can be controlled or changed in an experiment • anything that can change and affect the results in an investigation • (In a controlled experiment, the main variables are: • The independent variable • The dependent variable • The control

5. controlled experiment • An experiment in which all of the variables except for one remain the same.

6. independent variable • The thing in an experiment that you change on purpose. It is also known as the manipulated variable. • IT IS THE THING YOU CHANGE!!!!

7. dependent variable • predicted response to the change, what you think will happen because of the change you made (IV), the reason for doing the experiment • helicopter experiment: the change of the direction of the spin)

8. responding variable • another name for the dependent variable • The thing in an experiment that responds to the independent variable.

9. manipulated variable • Another name for the independent variable. • The thing in an experiment that you change on purpose.

10. Why should we use controlled experiments? • When you use a controlled experiment, only one variable, or part of the experiment, is changed at a time. • This means that your results/findings will be more reliable/accurate. • To be sure that what we changed on purpose (IV) is what caused the results

11. What is the difference between a constant and a control? • You do not change constants or controls. • The difference is that a control is the standard for comparison (the one thing that does not receive the change of the IV) and a constant is something that stays the same in each trial of the experiment (there will be multiple constants in an experiment. • Constants are not being compared to the other variables in an experiment.

12. What is the difference between an IV and a DV? • An IV is something you change on purpose in an experiment, and the DV is what responds to that change. • Helicopter experiment: • IV—fold of the blades • DV—change in direction of rotation • Egg-speriment • IV—the solution • DV—the change in mass (weight)

13. Chapter 1

14. Marine and Freshwater 25. What are the two types of aquatic ecosystems? • ~70% of the Earth’s surface is covered in water • Marine ecosystems—salt water • Freshwater ecosystems—only 3% of the water on the Earth’s surface!

15. Aquatic communities are influenced by the amount of light present, the availability of nutrients, and the presence of oxygen. • These factors determine which organisms can live in different aquatic biomes or communities.

16. Freshwater Ecosystems • has less than 1% salt

17. Differences among Freshwater • Standing water - lakes, ponds, wetlands • Ponds and lakes—bodies of fresh water that flow slowly or not at all • Lakes are generally deeper and larger than ponds • Producers—algae floating on the surface • Turtles, frogs, snails, dragonflies; fish

18. Moving water – estuaries, rivers, and streams • Rivers, streams, creeks, and brooks—freshwater that flows • streams-most begin in the mountains or hills; water flows rapidly; joins with other streams to form rivers (slows as it twists and turns) • organisms must be able to survive currents—trout; river otters and beavers

19. areas where water either covers the soil or is near the soil’s surface for all or part of the year; *can be fresh or salt water Wetlands

20. marshes, swamps, bogs • breeding grounds for fish, amphibians, birds, and aquatic animals • may form an estuary—a place at the mouth of a river where fresh water mixes with salt water from a bay or ocean (brackish) • shrimp, redfish, mullet

21. Estuary where freshwater and marine biomes meet Freshwater Saltwater

22. estuary where freshwater and marine biomes meet place at the mouth of a river where fresh water mixeswith salt water from a bay or ocean

23. coniferous trees with cones and thin, needle-shaped leaves

24. deciduous trees that have flat leaves that change color and fall off before winter

25. species • A group of similar animals that can breed to produce fertile offspring • Example: raccoons • Procyon lotor

26. A living thing is called an organism. Example: a deer

27. All of the organisms of the same species that live in an area at the same time is called a population. Example: a herd of deer

28. All the populations of all species that live in an area is called a community. Example: deer + rabbits + bears

29. All the organisms living in an area, as well as the non-living parts of their environment, is called an ecosystem. Example: deer + rabbits + bears + sunlight + soil + air water + carbon + nitrogen

30. ecosystems made up of all of the biotic and abiotic parts of the environment It includes the relationships of the organisms with each other.

31. Large geographic areas that have similar climates and ecosystems are called biomes. Example: tundra, taiga, desert, etc.

32. What is the order from smallest to largest? • Organism • Population • Community • Ecosystem • Biome

33. limiting factor anything that restricts the number of individuals that can live in an ecosystem This includes food, water, and living space.When resources are plentiful, a population generally grows.

35. carrying capacity the largest number of individuals of the same species that an area can support The carrying capacity is determined by the limiting factors in an area.

36. When a population reaches the carrying capacity, its size remains fairly constant. However, when environmental conditions change, the carrying capacity also changes.

38. energy Sun • All living things need _____ to grow and to carry out their activities. • They get this energy from their food or directly from the ____. • This energy is passed from one organism to another in an ecosystem.

39. producers living things that can make their own food by using energy in sunlight (autotrophs) Plants are one kind of producer and they make their food through photosynthesis.

40. consumers an organism that gets its energy by feeding on other organisms (heterotroph) Animals, fungi, some protists, and some bacteria are consumers.

41. decomposers • consumers that get energy by breaking down dead plants and animals. • They return materials stored in dead plants and animals to the soil, water, and air. • Then green plants use the materials to make food.

42. herbivores • animals that only eat plants (producers). • They are called • primary, or first level, • consumers.

43. carnivores • animals that eat meat

44. Carnivores can be secondary (second-level) consumers, which means they eat the primary consumers

45. …tertiary (third-level) consumers, which means they eat the secondary consumers.

47. omnivores • eat both plants and animals. • Most humans are omnivores.

48. food chain • a model of how energy passes from plants through a series of animals is

49. food webs • shows several interconnecting food chains

50. Food Webs Food webs show many possible feeding relationships and energy pathways among the organisms in an ecosystem.