Chapter 3 Academic Biology

Chapter 3 Academic Biology

1. Limiting factor – any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms
2. Availability of food & water
3. Predation
4. Temperature – timberline
5. Sunlight
6. Climate
7. Space

1. Tolerance – the ability of organisms to withstand fluctuations in biotic and abiotic factors
2. Fish and water temperature

1. Succession – orderly, natural changes and species replacements that take place over time e.g. abandoned parking lot over 30 years
2. Primary succession – the colonization of barren land (no living organisms)
3. Fire
4. Flood
5. Volcano
6. Pioneer species (Lichens & mosses) break up rock into soil
7. Ferns and weeds further break up soil
8. Seeds are carried by animals or blown by the wind
9. Secondary succession – the sequence of changes that takes place after an existing community is severely disrupted in some way (fire, flood, etc…) PREVIOUS LIVING ORGANISMS AND SOIL ARE PRESENT
10. Climax community – A stable, mature community that undergoes little or no change in species
11. Can last hundreds of years
12. Climax communities occur quicker through secondary succession because soil is already formed (primary succession takes longer due to soil formation)

1. Biomes – ecosystems with a similar climax community

1. Aquatic
2. Marine
3. Photic zone – layer of water where light penetrates (Phytoplankton and zooplankton)

i. Bays

ii. Intertidal zone , tide pools, & sandy beaches

(Clams, barnacles, snails, crabs)

iii. Estuaries (mixture of salt & fresh water e.g.

river delta)

1. Coral reefs

1. Aphotic zone – layer of deep water where light cannot penetrate (Decomposers & scavengers eat dead organisms off the ocean floor)

1. Freshwater
2. Lakes, ponds, rivers
3. Warm water holds more oxygen resulting in more species
4. Light penetration affects species variation
5. Swamps (have trees), marshes (no trees)
6. Wetlands – where land and water meet

1. Terrestrial – Sunlight, latitude, and rainfall determine climate

1. Tundra ( treeless land w/permafrost)
2. shallow rooted grasses
3. Mosquitoes & black hippaboscid flies in summer
4. Lemmings, weasels, arctic fox, snowshoe hare
5. Musk oxen, reindeer, & caribou

1. Taiga (coniferous forest)
2. Warmer and wetter than tundra biome
3. fir, hemlock, and spruce trees
4. Lynx, snowshoe hare, weasels, red squirrels
5. Caribou and moose

1. Desert (arid region with sparse to non-existent plant life)
2. Less than 25 cm of precipitation annually
3. Rain-shadow effect
4. Cacti and succulents have modified leaves and waxy cuticle to retain water
5. Kangaroo rat does not have to drink water
6. Coyotes, hawks, owls, roadrunners, snakes, lizards, & scorpions
7. Grassland – covered in rich soil and grasses
8. receive between 25 cm and 75 cm of precipitation annually
9. Have dry season and not enough water to support trees
10. Oats, rye, and wheat are typical grasses
11. Jack rabbits, deer, elk, bison, prairie dogs
12. Prairie (U.S.,Canada, Australia), steppes (Russia), savannas (Africa), and pampas (Argentina)
13. Deciduous forest – lose leaves each year
14. receive between 70 cm to 150 cm of precipitation annually
15. Maple, oak, birch, elm, ash hardwood deciduous trees
16. Squirrels, mice, rabbits, deer, bears, & migratory birds

1. Rain forest – contain the most species of organisms & receive greater than 200 cm of precipitation annually
2. Temperate rainforest – cool temperatures and high precipitation e.g. Seattle, Washington
3. Tropical rainforest – warm temperatures and high precipitation
4. Vertical layering of habitats

ia. Canopy – (25-45 m high) monkeys and birds habitat

ib. Understory – (1-25 m high) insects vines, ferns, shrubs, epiphytes which get water from air, birds, bats, snakes, tree frogs, chameleons, etc…

ic. Groundlayer – (0-1 m high) jaguars, rodents, ants, termites, earthworms, bacteria, fungi

1. Decomposers quickly break down organisms and together with the warm air replenish nutrients to the soil for rapid use.