Ecology dr clapp

Here are your flashcards formatted for Knowt import. Each card uses `

to separate the term from the definition, and

` separates individual cards:

---

Tropical Zone Climate and Rainfall

Tropical zones are warm and wet year-round with temperatures averaging 25-28°C and rainfall often exceeding 2,000 mm annually.

Tropical Rainforest Plant Adaptations

Large leaves capture maximum sunlight in the dense canopy; epiphytes like orchids grow on other plants to access light; drip tips allow excess water to run off preventing fungal growth; buttress roots provide stability in shallow, nutrient-poor soils.

Tropical Rainforest Animal Adaptations

Camouflage helps frogs and insects blend into vegetation; monkeys have prehensile tails for climbing; poison dart frogs use bright warning coloration; toucans have large beaks to reach fruit on thin branches.

Desert Water Conservation Examples

Cacti store water in succulent stems; deep roots access underground water; waxy cuticles reduce water loss; spines reduce surface area and provide shade; CAM photosynthesis opens stomata only at night; some plants drop leaves during drought.

Why Desert Animals Are Nocturnal

Desert animals are nocturnal to avoid extreme daytime heat exceeding 38°C, conserve water by reducing evaporation, and hunt when temperatures are cooler and humidity is higher.

Savanna Grass Fire Regrowth

Grasses regrow quickly after fires because their growing points (meristems) are at or below ground level protected from fire, they have extensive deep root systems with stored energy, and fire releases nutrients back into the soil.

Cheetah Hunting Adaptations

Cheetahs reach speeds up to 110 km/h; lightweight streamlined body reduces air resistance; large nasal passages and lungs increase oxygen intake; non-retractable claws provide traction; long muscular tail acts as a rudder; binocular vision gives excellent depth perception.

Deciduous Trees

A deciduous tree sheds its leaves annually in autumn to conserve water and energy during winter when photosynthesis is less efficient. They are usually found in temperate forests with moderate temperatures and distinct seasons. Examples include oak, maple, and birch.

Hibernation in Bears

Hibernation helps bears survive winter by lowering metabolic rate (heart rate drops from 40-50 to 8-10 beats per minute), slightly reducing body temperature, and utilizing stored fat for energy without eating, drinking, urinating, or defecating for months. Bears also recycle urea into proteins to prevent muscle atrophy.

Boreal Forest Conifer Adaptations

Conifers have conical shapes to shed snow, needle-like leaves with thick waxy cuticles to reduce water loss, evergreen nature to photosynthesize immediately when warm, dark color to absorb more solar radiation, flexible branches that bend under snow, and shallow wide-spreading roots for thin soils.

Tundra Animal Adaptations

Tundra animals have dense multi-layered insulating fur, store thick fat layers for energy, change coat color seasonally for camouflage, compact body shapes with short appendages to reduce heat loss, and migrate long distances to find food. Caribou have broad sharp hooves for digging through snow.

Mosses and Lichens Wind Avoidance

Mosses and lichens grow low to the ground in dense mats staying below strongest winds, have flexible structure that bends rather than breaks, colonize sheltered microhabitats like rock crevices, anchor firmly with rhizoids, and can survive complete desiccation then rehydrate when conditions improve.

Deep Roots and Grazing Resistance

Deep roots help grasses withstand grazing by storing energy reserves that mobilize for regrowth after grazing, anchoring plants firmly to prevent uprooting, accessing water during drought, and protecting meristems at or below soil surface where grazers cannot reach them.

Grassland Animal Adaptations

Prairie dogs and ground squirrels burrow for protection; bison and zebras use herding behavior for safety; pronghorn antelope evolved speed for open terrain; grass-colored coats provide camouflage; large ears and elevated vantage points detect predators; flat grinding teeth process tough grasses.

Streamlined Fish Bodies

Streamlined (fusiform) bodies reduce water drag and turbulence, allowing smooth water flow over the body surface. The pointed head cuts through water with minimal resistance, and the tapered tail region reduces the energy-wasting drag wake, conserving energy for longer swimming.

Dolphin and Whale Blubber

Blubber provides thermal insulation in cold ocean waters preventing heat loss, serves as energy-rich fat reserve for long migrations or food scarcity, helps maintain neutral buoyancy, provides cushioning against impacts, and releases metabolic water when metabolized.

Visible Light in Photosynthesis

Visible light is absorbed by chlorophyll and photosynthetic pigments (primarily red and blue wavelengths), exciting electrons that initiate the electron transport chain. Light energy splits water molecules (photolysis) and produces ATP and NADPH, which power the Calvin Cycle where CO₂ is fixed into glucose.

Radiation Reflected by Upper Atmosphere

The upper atmosphere reflects gamma rays and X-rays completely, absorbs most UV radiation (UV-C completely and most UV-B by the ozone layer), and absorbs some infrared radiation. Visible light, some UV-A, and radio waves pass through relatively unimpeded.

Autotrophs in the Carbon Cycle

Autotrophs absorb CO₂ during photosynthesis and convert it into glucose, fixing inorganic carbon into organic compounds. Phytoplankton alone produce 50% of world's oxygen and sequester significant carbon. Fixed carbon forms the base of food webs and can become fossil fuels over geological time when buried.

Why Plants Need Nitrogen

Nitrogen is an essential component of amino acids that make proteins, part of nitrogenous bases in DNA and RNA, a component of chlorophyll needed for photosynthesis, and required for enzyme production and function.

Why Plants Need Phosphorus

Phosphorus is a key component of ATP (energy currency of cells), forms the sugar-phosphate backbone of DNA and RNA, is an essential part of phospholipids in cell membranes, and is important for root development, flower and seed production, and energy transfer within cells.

The 10% Rule

The 10% rule states that only about 10% of energy transfers between trophic levels in a food chain, with 90% lost primarily as heat from respiration, undigested material, movement, and incomplete consumption. This explains why food chains rarely exceed 4-5 trophic levels and why energy pyramids are always upright.

Primary Consumers Controlling Plant Biomass

Primary consumers control plant biomass by directly eating plants to reduce living plant material, preventing overgrowth of dominant species, promoting diversity through selective feeding, stimulating new growth through moderate grazing, dispersing seeds through droppings, and returning nutrients to soil through waste.

Secondary Consumers

Secondary consumers are carnivores that eat primary consumers (herbivores) or omnivores that eat both producers and primary consumers. Examples include frogs eating insects, snakes eating mice, small fish eating zooplankton, spiders eating flies, and foxes eating rabbits.

Secondary Consumers Controlling Grazers

Secondary consumers keep grazers under control through direct predation reducing numbers, altering grazer behavior to avoid predation, preventing populations from exceeding carrying capacity, indirectly protecting plant communities from overgrazing (trophic cascade), and removing weak or sick individuals to prevent disease spread.

Tertiary vs Secondary Consumers

Tertiary consumers eat secondary consumers (carnivores eating carnivores) occupying the fourth trophic level, while secondary consumers eat primary consumers (herbivores) occupying the third trophic level. Tertiary consumers have less energy available due to the 10% rule and are typically fewer in number. Example: Grass → Grasshopper → Frog → Snake.

Apex Predators

An apex predator is a tertiary or quaternary consumer that has no natural predators as a healthy adult, occupies the highest trophic level, exerts top-down control on the ecosystem, has large home ranges with lower population densities, and plays a keystone role in maintaining ecosystem balance. Examples: lions, killer whales, great white sharks, polar bears.

Decomposers in Nutrient Cycling

Decomposers break down dead organic matter into simpler inorganic substances, releasing carbon, nitrogen, phosphorus, and sulfur back to soil, water, and atmosphere. They convert organic nutrients into inorganic forms plants can absorb (mineralization) and complete biogeochemical cycles. Without decomposers, nutrients would remain locked in dead organisms.

Detritivores

Detritivores are organisms that feed on detritus (dead decaying organic matter) and physically ingest and digest it internally. Examples include earthworms, millipedes, woodlice, dung beetles, sea cucumbers, fiddler crabs, springtails, and termites. They differ from decomposers (bacteria and fungi) which absorb nutrients externally.

Transpiration in the Water Cycle

Transpiration moves water from soil to atmosphere as plants absorb water through roots and release it as water vapor through leaf stomata. A single large tree can transpire hundreds of liters daily, contributing to atmospheric humidity and driving precipitation when water vapor condenses to form clouds.

Condensation in the Water Cycle

Condensation occurs when water vapor cools and changes from gas to liquid droplets at the dew point. It requires condensation nuclei (dust, salt, smoke particles) and results in cloud and fog formation. This process releases latent heat which can fuel weather systems and is essential for precipitation formation.

Runoff Positives and Negatives

Positives: replenishes surface water bodies, transports nutrients to aquatic ecosystems, contributes to groundwater recharge, deposits nutrient-rich sediments on floodplains. Negatives: carries pollutants into water bodies, causes soil erosion, excess nutrients cause eutrophication and algal blooms, sedimentation damages aquatic habitats, can contribute to flooding.

Decomposition in the Carbon Cycle

Decomposition breaks down dead organisms and waste, releasing CO₂ back to the atmosphere through decomposer respiration. Some carbon becomes soil organic matter (humus). This process frees carbon for reuse by producers and completes the carbon cycle. In anaerobic conditions, decomposition produces methane (CH₄).

Nitrogen Fixation

Nitrogen fixation converts atmospheric N₂ into ammonia (NH₃) and ammonium (NH₄⁺) carried out by nitrogen-fixing bacteria (free-living like Azotobacter, symbiotic Rhizobium in legume root nodules, cyanobacteria). Lightning and industrial Haber-Bosch process also contribute.

Nitrification

Nitrification is a two-step aerobic process: Nitrosomonas bacteria oxidize ammonia/ammonium into nitrite (NO₂⁻), then Nitrobacter bacteria oxidize nitrite into nitrate (NO₃⁻). Nitrate is the form most easily absorbed by plants and is essential for making nitrogen available to producers.

Ammonification

Ammonification is the process where decomposer bacteria and fungi break down organic nitrogen compounds from dead organisms and waste into ammonia (NH₃) and ammonium (NH₄⁺), converting organic nitrogen back into inorganic form available in soil for plants or nitrification. Also called mineralization.

Denitrification

Denitrification is the process where denitrifying bacteria (like Pseudomonas) convert nitrates and nitrites back into atmospheric N₂ gas in anaerobic conditions (waterlogged soils, wetlands). It completes the nitrogen cycle but can cause soil fertility loss and produces nitrous oxide (N₂O), a greenhouse gas.

Greenhouse Gas Heat Trapping

Greenhouse gases trap heat through the greenhouse effect: solar radiation warms Earth's surface, which re-radiates infrared radiation. Greenhouse gas molecules absorb this outgoing infrared and re-emit it in all directions including back toward Earth, trapping heat in the lower atmosphere. Without this effect, Earth's average temperature would be about -18°C instead of 15°C.

Greenhouse Effect on Climate Change

The enhanced greenhouse effect causes rising global temperatures (approximately 1.1°C since pre-industrial times), ocean warming and acidification, coral bleaching from warmer acidic waters, melting ice caps causing sea level rise, increased extreme weather events, shifting climate zones, and ecosystem disruption with extinction risks.

Phytoplankton

Photosynthetic plankton that are primary producers making approximately 50% of the world's oxygen. They capture and sequester carbon through photosynthesis controlling global CO₂ levels, form the base of aquatic food webs, and when they die, sink to the ocean floor taking carbon with them for long-term sequestration.

Zooplankton

Animal plankton that are primary consumers feeding on phytoplankton. They serve as food for larger consumers like fish and whales, forming the critical link between primary producers and higher trophic levels. A decrease in zooplankton can lead to fisheries collapse due to lack of food sources for fish.

Bacterioplankton

Bacterial plankton that absorb and cycle nutrients like nitrogen, phosphorus, and iron. They decompose organic matter in the water column, playing essential roles in nutrient cycling and energy flow, contributing to both production and decomposition processes in aquatic ecosystems.

Plankton as Bioindicators

Plankton serve as bioindicators because changes in their composition, abundance, and diversity signal shifts in water quality, temperature, nutrient levels, and pollution. They respond rapidly to environmental changes providing early detection of ecosystem stress, and nutrient overload from runoff can cause eutrophication reflected in plankton blooms.

Secondary Succession

Secondary succession is ecological recovery after a disturbance where soil remains intact. Process: disturbance removes vegetation, pioneer species (grasses, weeds) colonize first, intermediate species (shrubs, small trees) establish as conditions improve, and a climax community (mature stable ecosystem) eventually develops. Examples: after forest fires, abandoned farmland, hurricanes, or logging.

Pioneer Species

First organisms to colonize disturbed or bare areas. They are fast-growing, tolerant of harsh conditions, short-lived, produce many seeds, and are small in size. They stabilize soil, add organic matter, and create conditions for other species. Examples: lichens, mosses, grasses, weeds.

Intermediate Species

Species that establish during middle stages of succession between pioneer and climax communities. They have moderate growth rates, can tolerate some shade, are medium-sized (shrubs, small trees, pines), require developing soil, and increase biodiversity while transitioning the ecosystem toward climax community.

Climax Community

The final, stable, self-sustaining stage of ecological succession with maximum biodiversity. Species are slow-growing, long-lived, shade-tolerant, competitive, and large in size. They require well-developed nutrient-rich soil. Examples: mature hardwood forests and established grasslands.

Population Size Determinants

Population size increases through birth rate (natality) and immigration, and decreases through death rate (mortality) and emigration. Limiting factors include density-dependent factors (competition, predation, disease), density-independent factors (natural disasters, weather), carrying capacity, resource availability, and environmental conditions.

Photosynthesis and Cellular Respiration Carbon Relationship

Photosynthesis removes CO₂ from the atmosphere to make glucose (6CO₂

Human Impact on Carbon Cycle

Human activities disrupt the carbon cycle by burning fossil fuels releasing stored carbon as CO₂ faster than natural processes, deforestation removing carbon sinks, cement production releasing CO₂ from limestone, agriculture disturbing soil carbon and livestock producing methane, and land use changes reducing carbon storage. Atmospheric CO₂ has increased from ~280 ppm pre-industrial to over 420 ppm today.

Why Phosphorus is Essential

Phosphorus is essential as a component of ATP (energy currency of cells), forms the sugar-phosphate backbone of DNA and RNA, is part of phospholipids in cell membranes, provides structural strength in bones and teeth as calcium phosphate, regulates proteins through phosphorylation, and helps maintain cellular pH. Phosphorus has no atmospheric component and cycles through rock, soil, water, and organisms.

Intraspecific Competition

Competition within the same species for resources like food, mates, territory, and shelter. It drives natural selection and evolution, and can lead to territoriality, dominance hierarchies, and population regulation. Examples: two deer competing for food, male birds competing for mates.

Interspecific Competition

Competition between different species for similar resources like food, habitat space, water, and light. It can lead to competitive exclusion or niche partitioning and drives ecological relationships and community structure. Examples: lions and hyenas competing for prey, different plant species competing for sunlight.

Energy

The capacity to do work; flows through ecosystems in food chains and webs from producers to consumers.

Ecology

The scientific study of interactions between organisms and their environment, including both biotic and abiotic factors.

Ecosystem

A biological community of interacting organisms and their physical (abiotic) environment, including all biotic and abiotic characteristics in an area.

Biome

A large-scale community characterized by distinct climate and dominant vegetation types, such as tropical rainforest or tundra.

Symbiotic

A close, long-term relationship between two different species, which may be mutualistic, commensal, or parasitic.

Commensalism

A symbiotic relationship where one species benefits and the other is neither helped nor harmed.

Carnivore

An organism that consumes only other animals for energy.

Herbivore

An organism that consumes only plants or producers for energy.

Detritivore

An organism that feeds on dead, decaying organic matter by physically ingesting and digesting it internally.

Primary Producer

An autotroph that produces its own food through photosynthesis or chemosynthesis, forming the base of food webs.

Primary Consumer

An herbivore that eats primary producers, occupying the second trophic level.

Biotic

All living factors affecting an ecosystem including animals, plants, microorganisms, and fungi.

Abiotic

All non-living factors affecting an ecosystem including pH, temperature, water, sunlight, salinity, and currents.

Predation

The act of one organism (predator) hunting and consuming another organism (prey) for energy.

Predator

An organism that hunts, kills, and consumes other organisms for food.

Prey

An organism that is hunted, killed, and consumed by a predator.

Environment

The surroundings or conditions in which an organism lives or operates, including all biotic and abiotic factors.

Limiting Factors

Environmental conditions that limit population growth or distribution, including both density-dependent and density-independent factors.

Carrying Capacity

The maximum population size that an environment can sustainably support given available resources.

Energy Pyramid

A diagram showing energy transfer between trophic levels, illustrating the 10% rule where only about 10% of energy transfers to the next level.

Arrows on a Food Web

Indicate the direction of energy flow, pointing from the food source to the consumer.

Autotroph

An organism that makes its own food through photosynthesis or chemosynthesis (producer).

Heterotroph

An organism that consumes other organisms for food and energy (consumer).

Habitat

The area and resources used by a particular species, including both biotic and abiotic components of their environment.