Mr. Spahn’s Science Gateway Review

1. Mr. Spahn’s Science Gateway Review 2013-2014

2. Section 1 Ecosystems

3. What is an Ecosystem? • An ecosystem is a community of living organisms (plants, animals and microbes) in conjunction with the nonliving components of their environment (things like air, water and mineral soil), interacting as a system. • These biotic and abiotic components are regarded as linked together through nutrient cycles and energy flows. • As ecosystems are defined by the network of interactions among organisms, and between organisms and their environment, they can be of any size but usually encompass specific, limited spaces. • Some scientists say that the entire planet is an ecosystem.

4. Biome • A major biological community that occurs over a largearea of land. • Determined primarily by precipitation • Affected by elevation, latitude, soil type, and geographical features. • Biomes are climatically and geographically defined as similar climatic conditions on the Earth and are often referred to as ecosystems

5. Terrestrial Biomes

6. Terrestrial Biomes Tropical Rain Forest • Rain: 200-450 cm (80-180 in) per year (A lot of rain) • Rich in number of species (many different types of organisms) • Central America, South America, Africa, Asia • Examples of Animals and Plants: tree frog, monkeys, birds, green canopy Desert • Rain: fewer than 25 cm (10 in) per year (Very little rain) • Sparse vegetation • May be warm or cold • Examples of Animals and Plants: Cactus, snakes, lizards, nocturnal animals

7. Terrestrial Biomes Temperate Deciduous Forest • Rain: 75-250 cm (30-100 in) per year • Mild climate, plentiful rain • Deciduous trees shed leaves in fall • Warm summer, cold winter • Mammals hibernate in winter, birds migrate • Eastern US, Southeastern Canada, Europe, Asia • Examples of Animals and Plants: Bears, Deer, Oak Trees Tundra • Located between taiga and poles • 20% of Earth’s surface • Rain: very little rain (less than 25 cm (10 in) per year) • Permafrost 1m deep (3ft) • Examples of animals: foxes, lemmings, owls, caribou, lichen

8. Terrestrial Biomes Temperate Grasslands • Halfway between equator and poles • Interior of North America, Eurasia, South America • Fertile soil, used for agriculture • Examples of Animals and Plants: Grazing animals (Bison), grasses, field mice Coniferous Forest • Cone bearing trees prevalent • Pacific Northwest (temperate rain forests); cold and wet • Northern coniferous forest is called aTaiga • Winters long and cold; precipitation in summer • Examples of Animals and Plants: pine, spruce, fir, elk, moose, deer, wolves, bears, lynx.

9. Aquatic Biomes Freshwater Communities • Standing bodies of water: lakes, ponds • Moving bodies of water: streams, rivers • Wetlands: swamps, marshes, bogs • ~2% of Earth’s surface • Examples of Animals and Plants:fish, arthropods, mollusks, microscopic organisms Marine Communities (salt water) • 75% Earth’s surface covered by ocean • Average depth 3km (1.9mi) • Mostly dark and cold • Photosynthetic organisms mostly towards surface • Heterotrophic organisms throughout • Examples of Animals and Plants:Fish, plankton (algae, diatoms, bacteria).

10. AQUATIC BIOMES

11. TERRESTRIAL BIOMES

12. Important Ecological Terms • Abiotic factors • Nonliving chemical or physical factors in the environment. • Examples: Air, soil, water, wind • Biotic factors • Living organisms in the environment. • Examples: Plants, animals, fungi, microorganisms

13. Important Ecological Terms • Ecosystem • All living and nonliving things in a given area • Community • All living organisms that inhabit a given area. • A group of populations • Population • A group of individuals belonging to the same species that live together in the same area

14. Important Ecological Terms • Competition • Two or more organisms require the same resource that is in limited supply. • Food, shelter, light, water, mates • The strongest organism will win the competition and will be more likely to live and pass its genes on to the next generation (natural selection). • Habitat • Place or environment in which populations live • Niche • Role of a species in an ecosystem • Relationships, activities, resources used

15. Section 2 Energy Transformations in Biology

16. Respiration and Photosynthesis • Photosynthesis • Process of using energy from the sun to produce sugars (glucose) • 6CO2+ 6H2O + Light Energy  C6H12O6 +6O2 • Occurs in chloroplast of plants and some algae • Photosynthesis produces all of the energy available in most ecosystems. • Some ecosystems that are not exposed to any sunlight get their energy chemically.

17. Respiration and Photosynthesis • Respiration • Process of using energy from sugar (glucose) to produce ATP • C6H12O6 +6O2 6CO2 + 6H2O + 38ATP • Occurs in mitochondria • Occurs in both animals and plants • ATP provides energy to do work in the cell • When ATP is used, it is converted to ADP; respiration then uses energy in sugars to convert ADP back to ATP by adding a phosphate.

18. Respiration and Photosynthesis • How are photosynthesis and respiration related? The products of respiration are the reactants of photosynthesis; the products of photosynthesis are the reactants of respiration.

20. Respiration and Photosynthesis • Where and how are excess sugars stored in plants? Excess sugars are stored as starch in the roots. Starch is a polymer of glucose. • Where and how are excess sugars stored in animals? Excess sugars are stored as glycogen in the liver of animals. Glycogen is a polymer of glucose.

21. Flow of Energy Through an Ecosystem • In order to live, organisms must obtain energy and nutrients • Heterotrophs • Obtain energy and nutrients from the food they eat • Autotrophs • Obtain energy from the sun • Obtain nutrients from the soil. • Chemotrophs • Obtain energy from chemical reactions, not the sun. • Examples are the breakdown of rocks in caves (no sunlight), and the breakdown of gases at undersea vents (no sunlight).

22. Chemotrophs • Chemoautotrophs (chemosynthesizers) are bacteria that oxidize reduced inorganic substances • (typically sulfur and ammonia compounds) • and produce complex organic compounds. oxygen reduced inorganic compounds complex organic compounds chemoautotrophs

23. Chemosynthesis near hydrothermal vents

24. Flow of Energy Through an Ecosystem • Producer • Uses energy from the sun and carbon from the environment to make its own food. • “Bottom of the food chain” • Why are producers necessary in any ecosystem? Make energy from the sun available/usable for heterotrophs.

25. Flow of Energy Through an Ecosystem • Consumer • Obtains energy through eating other organisms • Herbivore: eats only plants • Carnivore: eats only animals • Omnivore: eats both plants and animals • Primary consumer: eats producers • Secondary consumer: eats the consumers that eat the producers • Tertiary consumer: eats the consumers that eat the consumers that eat the producers • Means of obtaining nutrition • Predation • Ecological interaction in which one organism (predator) feeds on another living organism(prey). • Predator may or may not kill the prey. • Scavenging • An animal ingests dead plants, animals, or both. • Vultures, termites, beetles

26. Decomposers • Decomposer (Saprophytes) • A type of comsumer • Breakdown (absorb nutrients from) non-living organic material—corpses, plants, waste of living organisms—and convert them to inorganic forms. • Bacteria, fungi • Why are decomposers necessary in any ecosystem? Recycle nutrients.

27. Flow of Energy Through an Ecosystem Food Chain • Linear pathway of energy transport through an ecosystem (only one arrow goes to and from each link in the chain). • algaekrillcodsealkillerwhalebacteria • Producers always come first in the food chain. • Decomposers always come last in the food chain; they will break down dead organisms and allow nutrients to be recycled. • Arrows indicate the direction in which energy flows through the ecosystem.

28. Trophic Levels and Food Chains • The trophic level of an organism is the position it occupies in a food chain. • Primary consumers include insects and zooplankton • Secondary consumers include many small mammals, such as rodents, and small fishes that eat zooplankton • Tertiary consumers, such as snakes and bigger fish eat mice and other secondary consumers • Quaternary consumers include hawks and killer whales. Quaternary consumers Carnivore Carnivore Tertiary consumers Carnivore Carnivore Secondary consumers Carnivore Carnivore Primary consumers Zooplankton Herbivore Producers Plant Phytoplankton A marine food chain A terrestrial food chain

29. Flow of Energy Through an Ecosystem Food Web • A network of interconnected food chains in an ecosystem • Producers are at the beginning. • Decomposers are at the end. • Arrows indicate the direction in which energy flows through the ecosystem.

30. Construct two distinct food chains (different starting and ending points) from the food web pictured with 4 organisms.

31. Practice: • How does a food chain prove the Law of Conservation of Matter and Energy? The energy is not disappearing but is being transferred from one organism to another.

32. Energy Pyramids • Energy Pyramid -a diagram that represents the cumulative loss of energy from a food chain • There is a 90% decrease from each trophic level to the next. • The Law of Conservation of Energy states that matter can not be created or destroyed. Yet the energy pyramid shows that less energy is available as you move up a food chain.

33. Not all of the organism is consumed. • Not all parts are digestible so they are excreted. • Some energy is lost in excretory substances. • Considerable heat is lost by respiration. Why is the Percentage of Energy Transfer Between Trophic Levels so Low?

34. Conservation of Energy Plant material eaten by caterpillar 100 kilocalories (kcal) 35 kcal Cellular respiration 50 kcal Feces 15 kcal Growth

35. Pyramid of Biomass Biomass is the total weight of living matter at a specific trophic level. A pyramid of biomass represents the total weight of living material available at each trophic level. The amount of biomass decreases at higher trophic levels. Pyramid of Biomass 1 kilogram of human tissue 10 kilograms of beef 100 kilograms of grain

36. Pyramid of Numbers A pyramid of numbers shows that populations decrease at each higher trophic level. Population sizes decrease in relation to biomass, energy and sustainability . Fox (1) Birds (25) Grasshoppers (250) Grasses (3000) Pyramid of Numbers

37. Carbon Cycle • Carbon is the key ingredient in all living organisms • Processes involved: biological (example: photosynthesis), geochemical (example: release of CO2 by volcanoes), human activity (example: burning of fossil fuels) • Producers: Plants take in CO2 and make sugar by photosynthesis. • Consumers: Animals eat plants to get energy (respiration) from sugar and make proteins from the carbon. • Breath out CO2 as a waste product of respiration. • Animals die and decomposers break down the carbon and other elements back into the soil and air for plants to use again.

38. Carbon Cycle CO2 in atmosphere Photosynthesis Burning Producers Wood and fossil fuels Cellular respiration Higher-level consumers Primary consumers Decomposition Bacteria Detritus

39. Nitrogen Cycle • All organisms require nitrogen to build proteins • Forms of nitrogen: N2 in atmosphere; NH3, NO3-, NO2- in wastes; nitrate from fertilizers • Some bacteria convert N2 into NH3 during nitrogen fixation. • Some bacteria convert nitrates into N2during denitrification.

40. Nitrogen Cycle

41. Water Cycle • The never-ending circulation of the earth’s water as it makes its long journey from the oceans, to the air, to the land, and back to the oceans again • All organisms require water to survive. • Processes: evaporation, transpiration, condensation, precipitation, seepage, runoff

42. Water Cycle

43. How much water is on the earth? There are about 326 million cubic miles of water. There are over a million gallons of water per cubic mile. How much of the earth’s water is fresh? Only about 3% of the earth’s water is fresh. About 75% of the earth’s fresh water is frozen in ice caps and glaciers. Some Cool Water Facts • How much water does a person use every day? • -On average, each person in the United States uses more than 100 gallons of water a day in the home. • How much water do living things contain? • -All living things consist mostly of water. Humans are 60% water. • What is the largest single use of water? • -The largest single use of water is by industry. It takes about 80 gallons of water to make the paper for one Sunday newspaper. • Can water ever be used up? • -Water is used and reused over and over again—it is never used up. Every glass of water you drink contains molecules of water that have been used countless times before.

45. Section 3 Ecological Changes

46. Important Ecological Terms • Succession • The series of predictable changes that occurs in a community over time • Primary succession occurs on a surface where no soil exists. Example: bare rock, areas covered by volcanic ash • Secondary succession occurs in an area where a disturbances changes an existing community without destroying the soil. Example: plowed land, area burned by wildfire • As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community

47. ECOLOGICAL SUCCESSION • Pioneer community– the first community to enter an area • Climax community– the final or most stable community in an area

48. Primary Succession M-DCC / PCB 2340C

49. Primary Succession • Lichen (algae and fungi) are the first to grow on the volcanic rocks • They help break up the volcanic rocks • When the lichen die, they add organic matter to help form soil • Plants start to grow on the soil • Trees replace bushes as time goes by

50. Secondary Succession