Biology Test 1 2024

• Ecosystem


  Formed by organisms interacting with each other and their non-living environment in a balanced way
• Desert


  A major ecosystem in Australia characterized by arid conditions and sparse vegetation
• Biotic factors


  Living organisms in an ecosystem, e.g., insects, trees, fish
• Sustainable ecosystem


  Maintains energy input, biodiversity, and necessary substances for survival
• Sun


  Ultimate source of energy for ecosystems
• Sustainability


  Ecosystem's ability to support diverse species in suitable conditions
• Photosynthesis


  Process converting light energy into sugars by plants
• Glucose


  Product of photosynthesis used in cellular respiration or stored as starch
• Chlorophyll


  Chemical in chloroplasts that traps sunlight for photosynthesis
• Cellular respiration


  Process converting glucose and oxygen into water, carbon dioxide, and energy
• Food chain


  Linear sequence showing energy transfer in an ecosystem
• Producer


  Organism that produces food for other organisms
• Consumer


  Organism that consumes other organisms for energy
• Energy flow


  Transfer of energy through trophic levels in an ecosystem (10%, 90% rule)
• Decomposers


  Organisms that break down dead matter into nutrients for the ecosystem
• Population


  Group of organisms of the same species living in a specific area
• Carrying capacity


  Maximum population size an environment can sustain
• Exponential growth


  Population growth where numbers increase rapidly over time
• Food web


  Complex network showing multiple interconnected food chains in an ecosystem
• Adaptation


  Trait or behavior that helps an organism survive and reproduce in its environment
• Fire management


  Use of fire by indigenous people to manage the environment
• Drought


  Extended period of low precipitation affecting plant and animal populations
• Flooding


  Inundation of land by water, impacting plant and animal populations
• Pyramid of Numbers


  Shows the number of organisms at each trophic level
• Pyramid of Biomass


  the total amount of living material at each level at any one time (always a triangle shape)
• Competition (win/lose)


  2 organisms competing for a limited resource - food, shelter, space eg. African animals compete for water
• Predation (win/lose)


  one organism benefits, the other loses. fox-rabbit, croc-fish.
• `Parasitism (win/lose)


  one organism benefits and the other is harmed but not normally killed - mosquitoes, fleas, worms
• Mutualism


  a relationship between two different types of organisms where both benefit from each other, must be different species eg. cleaner fish - shark, ox peaker - rhino
• interspecific


  different species compete
• intraspecific


  same species compete
• Overcoming Competition - Plant Strategies

  1. allelopathy - toxic chemicals are produced by one organism and directed at potential threats

  2. strangler figs start their seeds high in the canopy so the roots grow downwards and strangle the tree which originally supported the fig.

  3. desert plants space themselves protecting an area from which their roots will draw water from.
• Overcoming Competition - Animal Strategies

  1. different habitats - separating the habitat between young and the adults to reduce competition within the species.

  2. territorial behaviors - birds use displays/calls to repel others of the same species.

  3. infanticide - male lions and gorillas may kill younger males (even their own young) to reduce competition for females
• Desert Biome


  Located - Victoria, WA, NT, Central Australia

  Biotic Factors - Bilbies, King brown snake, Honey Grevillea, Blue Malle

  Abiotic Factors - Precipitation + Temperature

  Human Impacts - Desertification - vegetation decrease
• Wetlands Biome


  Located - South/ South-east of Australia

  Biotic Factors - Black Swan, Long neck Turtle

  Abiotic Factors - Topography + Water quality

  Human Impacts - Introduced species - Cane toad
• Rainforest Biome


  Located - North and Costal regions of Australia

  Biotic Factors - Southern Cassowary, Quail

  Abiotic Factors - Strangler figs + Stinging trees

  Human Impacts - Hunting + Pollution + Fishing