Unit 2 Biology

Define weather

Short-term conditions of the atmosphere

Define climate

Overall atmospheric conditions

Define biodiversity

The variety of different species, alleles, communities, and nonliving environments

Define population

Members of a particular species within a defined area, found in the same time and place and actually/potentially interbreeding

Define ecology

the study of interactions of organisms with their environment

Ecosystem

All the organisms and their nonliving environment within a defined area.

Define sustainability

an ecosystem's ability to independently maintain its natural balance, biodiversity, and productivity over time,

Define conservation

The management, protection, and preservation of the natural environment and its resources, to ensure their long-term survival.

Tropical Rain Forests (general climate in terms of temperature and precipitation, and lifeforms found)

• Average temperature is very warm-hot

• Rain-fall is generally heavy; it’s moist

• Tree-orientated organisms: towering trees, tree-dwelling orchids, red-eyed tree frogs, and fruit-eating toucans

  • Soil is very infertile; vegetation absorbs most nutrition

• High biodiversity

Tropical Deciduous Forests (general climate in terms of temperature and precipitation, and lifeforms found)

• Annual rainfall is high, but there are wet and dry seasons.

• Trees that shed their leaves during dry seasons

• Migration, hibernation and drought-orientated organisms: elephants, bears, slugs, bamboo

• High biodiversity

Tropical Scrub Forests and Savannas (general climate in terms of temperature and precipitation, and lifeforms found)

• Moderate rainfall overall; has dry and wet seasons

• Short and spread out deciduous trees; acacia trees

• In drier areas grasses are the dominant vegetation; these are savannas

• Most diverse array of large mammals on Earth: rhinos, elephants, and giraffes, lions, leopards, hyenas

Deserts (general climate in terms of temperature and precipitation, and lifeforms found)

• Variable dryness

• Can have freezing temperatures or boiling temperatures

• Widely spaced vegetation and large areas of bare ground

• Heat and drought-orientated organisms: cacti, bats, turtles, kangaroos

• Some deserts have a very brief rainy season, in which a whole year’s rain falls in just a few weeks

Chaparral (general climate in terms of temperature and precipitation, and lifeforms found)

• Overall dry

  • Cool, wet winters and hot and dry summers

• Drought and fire-resistant organisms; shrubs and small trees, coyote, lizards, jackrabbits

Grasslands (general climate in terms of temperature and precipitation, and lifeforms found)

• Hot summers and cold winters

• Moderate rain

• Lots of grass and virtually no trees, except along rivers

• Fire, drought, and camoflauge organisms; prairie dogs, ground squirrels, eagles, foxes, coyotes, bison

Temperate Deciduous Forests (general climate in terms of temperature and precipitation, and lifeforms found)

• Moderate rainfall; higher than grassland

• Deciduous trees

• Below-freezing winters

• Harsh-winter and decomposer organisms: earthworms, fungi, salamanders, raccoons, deer, bears, coyotes, and beavers

Temperate Rain Forests (general climate in terms of temperature and precipitation, and lifeforms found)

• High rainfall

• Huge conifers such as spruce, Douglas fir, and hemlock

• Mosses, fungi, and ferns

Northern Coniferous Forests / Taiga (general climate in terms of temperature and precipitation, and lifeforms found)

• Harsher than in temperate deciduous forests, with long, cold winters and short growing seasons

• Moderate-low precipitation; SNOW

• Harsh-winter-orientated: conifers, black bears, moose, snowshoe hares

Tundra (general climate in terms of temperature and precipitation, and lifeforms found)

• Severe temperatures and wind

• Low precipitation

• Permafrost

• Cold-orientated: arctic fox, caribou, mosses, mosquitoes

Freshwater Lakes - Littoral zone

Littoral zone

• Near shore

• Abundant sunlight and nutrients

• Anchored and fully submerged plants, photosynthetic protists, and phytoplankton and zooplankton

• Crayfish, frogs

Freshwater lakes - limnetic zone

Limnetic zone

• Further from shore, only enough light penetrates to support photosynthesis by phytoplankton

• Fish

Freshwater lakes - profundal zone

Profundal zone

• Light is too weak for photosynthesis to occur

• Catfish and detritivores and decomposers

Freshwater lakes - oligotrophic

Oligotrophic Lakes

• Few nutrients → little life

• Clear water, deep light penetration

Freshwater lakes - eutrophic

Eutrophic Lakes

• High nutrients (sediment, organic material, phosphates, nitrates)

• Dense plants & phytoplankton → murky water

• Shallow limnetic zone

• Dead organisms sink → decomposers use O₂ → profundal zone low in oxygen, little life

Streams and Rivers

• Source (mountains): Cold, clear, little sediment, sparse phytoplankton. Algae on rocks → insect larvae → trout (need high O₂).

• Transition zone (lower elevation): Streams merge, wider & slower, warmer, more sediment/nutrients. Supports aquatic plants, algae, phytoplankton. Fish: bass, bluegill, perch (moderate O₂ needs).

• Floodplain / lower river: Warm, wide, slow, murky with phytoplankton. Decomposers lower O₂, but carp & catfish survive (low O₂ tolerant). Floods deposit sediment on land.

• End: River drains into lake or estuary.

Freshwater wetlands

• algae, phytoplankton, cattails, marsh grasses, birds, beavers, otters, bacteria