EOCT Review

1. EOCT Review Domain IV - Ecology

2. Ecology • The study of the interactions between living things and their environment • Biotic factors – living organisms in an ecosystem • Plants, animals, bacteria • Abiotic factors – nonliving factors in an ecosystem • Climate, light, soil, water

3. Organization of Life • Organism – an individual • A cow • Population – a group of organisms of the same species • A herd of cows • Community – several different species living in the same area • A herd of cows, insects, grass, trees • Ecosystem – all of the living and nonliving components of an area • Cows, insects, grass, trees, rain, streams, rocks • Biosphere – the entire planet

4. Populations • Population density – the number of organisms living in a given area • Growth rate – change in population size • Exponential growth – under ideal conditions, with unlimited resources, the population increases exponentially • J-shaped curve • Logistic growth – as resources become less available, the growth of a population slows or stops • S-shaped curve • Carrying capacity – the maximum number of individuals an environment can support

5. Population Graphs

6. Limiting Factors • Density-dependent limiting factors • The more organisms there are, the greater the impact • Ex. Competition, predation, parasitism, crowding • Density-independent limiting factors • The impact is the same regardless of population size • Ex. Weather, fires, droughts, floods, human activities

9. Energy Flow • Producers (autotrophs) – organisms that make their own food • Plants, photosynthetic bacteria, algae • Consumers (heterotrophs) – organisms that need to feed on other organisms • Trophic levels – each step in a food web or food chain • First level is producers, second level is primary consumers, third level is secondary consumers, etc.

10. Consumers • Herbivore – eats plants • Ex. deer • Carnivore – eats other animals • Ex. lion • Omnivore – eats both plants and animals • Ex. raccoon • Decomposer – breaks down dead organisms • bacteria

11. Food Chains and Food Webs • Show the flow of energy and matter through an ecosystem

12. Question #1 • In the food chain below, which population will most likely decrease if snakes are removed from the food chain? • grass • grasshopper • frog • hawk

13. Energy Pyramids • Show how energy decreases at each trophic level • The total energy transfer from one level to the next is only about 10% • Some of the energy is used by the previous organism • Some of the energy is lost as heat

14. Other Ecological Pyramids

15. Water Cycle

16. Carbon Cycle

17. Nitrogen Cycle

18. Phosphorus Cycle

19. Ecological Succession • Primary succession – occurs on surfaces where no soil exists (no previous life) • Glaciers, lava • Usually lichens and mosses are the first organisms (pioneer species) to move in • Secondary succession – occurs when a disturbance changes the existing community without removing the soil • Tornado, clear-cutting • Climax community – the final, stable community

20. Ecological Succession

21. Resources • Renewable resource – a natural resource that is replaced or replenished by natural processes • plants, water • Nonrenewable resource – a natural resource that is available only in limited amounts • Soil, fossil fuels, metals • Reduce, reuse, recycle

22. Extinction • Extinction – the complete disappearance of a species • Threatened species – species that are declining rapidly • Endangered species – when a species numbers drop so low that extinction is almost inevitable

23. Pollution • The contamination of soil, water, or air and is the result of human activity • Pollutant – any substance that is harmful or is a waste product • Air pollution – caused primarily by the burning of fossil fuels • Acid rain – rain with a pH lower than 5 • Caused by air pollutants

24. Pollution • Water pollution – caused by contaminants from sewers, industries, farms, and homes • Enters water sources such as lakes, rivers, groundwater, and oceans • Sewage, chemical wastes, fertilizers

25. Greenhouse effect • Earth’s atmosphere traps solar radiation • Keeps Earth at a ‘livable’ temperature • An increase in the greenhouse effect (due to excessive greenhouse gases) is believed to be the cause of global warming • Ozone layer – prevents lethal doses of UV radiation from getting to Earth • The ozone layer is being depleted by CFCs

26. Question #2 • The theory of global warming suggests that a trend toward warmer temperatures on Earth will cause glaciers to lose mass. A major consequence of glacial melting is • flooding coastal regions • destruction of fossil records • increased saltiness of the ocean • increase in atmospheric carbon dioxide

27. Plant Adaptations • Tropism – a plant’s response to their environment • Geotropism – response to gravity • Phototropism – response to light • Thigmotropism – response to touch

28. Plant Adaptations • Hormones – chemical messengers • Auxin – causes cell elongation • Gibberellins – growth hormone • Causes plants to grow taller, increases rate of germination and bud development, larger fruit • Flowers and cones are adaptations that aid in plant reproduction

29. Question #3 • What characteristic of some pine trees allows the species to survive disasters? • modified leaves form needle bundles • seeds that germinate after fires • pollen that is easily carried by wind • bark that is lightly colored

30. Animal Adaptations • Behavior – anything an animal does in response to stimuli in its environment • Innate behavior – inherited behavior • Reflexes – automatic responses that require no thinking • Instincts – may take longer and may be a combination of behaviors (ex. Mating rituals) • Territorial – protecting or defending your territory (which contains breeding grounds, feeding areas, shelter, etc.) • Reduces conflict, controls populations, decreases competition

31. Animal Adaptations • Migration – instinctive, seasonal movement of a species • Hibernation – the body temperature drops, oxygen consumption decreases, breathing rates decrease • Estivation – animals reduce the rate of their metabolism due to extreme heat, lack of food or long periods of drought

32. Animal Adaptations • Mechanical defenses – physical structures such as claws, sharp tusks, stingers, and shells • Chemical defenses – chemicals such as poisons or toxins • Camouflage – enable the organism to blend into its environment or appear to be something they are not

33. Question #4 • A group of organisms of a certain species that is in one area at a given time is known as a(n) • ecosystem • community • population • trophic level

34. Question #5 • As energy flows through an ecosystem, at each trophic level it • increases • decreases • fluctuates • remains the same

35. Question #6 • Predators often feed on weak or sick animals in an ecosystem. The role of the predator is described as its • community • habitat • niche • population

36. Question #7 • The dodder is a land plant that parasitizes other plants. It grows in long thin strands that penetrate the host plant and absorb water, minerals and carbohydrates. Unlike other land plants, the mature dodder does not require • nutrients • water • air • sunlight

37. Question #8 • The state of California has several large cities and very productive croplands that divert and use large amounts of water from rivers. What is one damaging effect of this use of water from the rivers? • Increased amounts of solid waste pollution in the oceans • Decreased amounts of fresh water in marshes and estuaries • Changes in local rainfall amounts • Changes in upstream water tables

38. Question #9 • Plants that live in the rainforest have many adaptations to their environment. Some plants such as vines have adaptations which allow them to attach themselves to the trunks of trees. These adaptations allow vines to successfully compete for which of the following limiting resources in the rainforest? • sunlight • water • carbon dioxide • oxygen

39. Question #10 • Lightning causes a fire that destroys all the plants in a forest community. Which of the following is most likely to be the first to occupy the burned area? • oak seedlings • pine trees • grasses and annual plants • woody shrubs

40. Question #11 • Pilot fish and sharks have a relationship where the pilot fish eats bits of food that the shark drops or leaves behind. The shark is unaffected by the pilot fish behavior. Which of the following best roles describes the pilot fish? • predator • herbivore • scavenger • parasite

41. Question #12 • Birds have been observed puffing up their feathers under certain conditions. By trapping air between the feathers, this behavior helps the bird • hide from enemies • expend less energy during flight • shelter offspring • trap body heat

42. Answers • D • A • B • C • B • C • D • B • A • C • C • D

43. Information and Images Obtained From: • http://www.doe.k12.ga.us/ci_testing.aspx?PageReq=CI_TESTING_EOCT&SubPageReq=GUIDES • Google image search • Campbell, Neil A. and Reece Jane B (2001). "6". Biology. Benjamin Cummings. • Miller, Kenneth R. and Levine Joseph S. (2002). Biology. Prentice Hall.