biology quiz 2

• Ecology is the study of how living things interact with each other and their environment
• An ecosystem is made up of all living (BIOTIC) and non-living (ABIOTIC) factors
• Organism: a single living thing that obtains food, water, and shelter to live, grow, and reproduce in its habitat (environment)
• Population: A group of interbreeding organisms (species) living in the same area
• Community: all the populations in an ecosystem
• Ecosystem/Biome: Includes all the living (biotic) & nonliving (abiotic) features of an environment
• Biosphere: All of the life present on the planet including plants, animals, bacteria, protists, and fungi
• Organisms → Population → Community → Ecosystem/Biome → Biosphere Smallest —> Largest
• Producers (Autotrophs): create their own food source (glucose) using energy from the Sun in the process of photosynthesis
• Consumers (Heterotrophs): get their food from other sources. There are 4 types:

  • Herbivores: consumers with specialized digestive structures adapted to eat only PLANTS
  • Carnivores: consumers with specialized digestive structures adapted to eat only OTHER ANIMALS
  • Omnivores: consumers with specialized digestive structures adapted to eat both PLANTS and ANIMALS
  • Scavenger: carnivores that eat the remains of dead organisms
  • Detritivores (Decomposers): consumers that break down decaying material and return nutrients to the soil
• Food Chain: series of events in which one organism eats another and obtains energy
• Energy Pyramid:

  • The sun is the ultimate source of energy for all living organisms
  • As you go up the food chain/energy pyramid, the amount of available energy decreases because you are getting further away from the original source of energy, the sun
• Bioaccumulation: The accumulation of toxins, pesticides, etc. in an organism as it gets older and consumes more toxins
• Biomagnification: An increase in the concentration of a toxin as it moves up the food chain
• Exponential Growth: Unlimited population growth; birth rate and death rate are constant(j curve)
• Logistic Growth: Limited population growth; birth rate and death rate change depending on the population size and competition for resources(s curve)
• Carrying capacity (K): The number of individuals that can be supported in an area given the amount of natural resources available
• Density-Dependent Factors: Affect large populations more than small populations depends on population size
• Density-Independent Factors: Affect large and small populations equally
• Immigration is the movement of individuals into a population
• Emigration is the movement of individuals exiting out of a population
• Interactions of Living Things:

  • Symbiosis: close relationship between two species benefiting at least one
  • Predation: predator kills prey for food
  • Competition: struggle between organisms for limited resources
• Mutualism: Both species benefit

  • Cow gets insects removed and Black-faced Langur (monkey) gets food
  • Egyptian Plover bird gets food and Crocodile gets insects removed
  • Bees get nectar from flowers and flowers get pollinated
• Commensalism: One species benefits while the other remains unaffected

  • Clownfish uses sea anemone to hide from predators
  • Cattle egret forages among cattle and horses for insects
  • Remora swims closely to the shark for protection
• Parasitism: One species benefits while the other is harmed

  • Mosquitoes get blood from animals and plasmodium uses human blood cells to reproduce
  • Tapeworms steal food from their hosts
• Ecosystems are made up of biotic and abiotic factors
• Water, nitrogen, and carbon cycles bring nutrients into ecosystems
• Water cycle:

  • Processes include condensation, transpiration, precipitation, surface runoff, groundwater, infiltration, and evaporation
• Nitrogen cycle:

  • Nitrogen is essential for organisms to live and grow
  • Nitrogen fixation is the process of converting atmospheric nitrogen into a usable form with the help of bacteria
  • Plants use fixed nitrogen like ammonium and nitrates
  • Denitrifying bacteria convert nitrogen back into the atmosphere
  • it helps make proteins and amino acids
• Carbon cycle:

  • Plants take in carbon dioxide through photosynthesis and release oxygen
  • Animals inhale oxygen and exhale CO2 through respiration
  • Human activities have influenced carbon levels in the atmosphere
• Greenhouse Effect:

  • Naturally occurring process that keeps us warm
  • Human activities adding carbon to the atmosphere lead to global warming or Global Climate Change
• Factors affecting climate change:

  • Burning of fossil fuels
  • Deforestation
  • Human causes
  • Volcanic eruptions
  • Geological processes
  • Natural causes
• Healthy ecosystems are biodiverse, meaning they have a variety of living organisms
• In a healthy ecosystem, organisms have a niche (role) and competition is low
• The study of populations and the factors that affect population size is called demography
• Biodiversity is important for keeping ecosystems healthy and providing benefits for humans
• Benefits of biodiversity for humans include oxygen, diverse diets, materials, and medicines
• Negative impacts on biodiversity by humans include population growth, technology, consumption of resources, and waste production
• Habitat loss is the number one threat to biodiversity
• Deforestation is the mass removal of trees that can take away habitats for species and contribute to climate change