Ecology(redundant ai import)

• What is the definition of an ecosystem?

  A community of organisms and how they are affected by and affect the abiotic environment.
• What is a habitat?

  The place where an organism lives.
• How is a species defined?

  Organisms with similar characteristics that can breed together to produce fertile offspring.
• What is a population?

  The number of organisms of the same species in the same place at the same time.
• What is a community in ecological terms?

  The different populations and their biotic interactions in a habitat.
• What are abiotic factors?

  Non-living factors in an ecosystem, such as soil pH, nutrient availability, water, temperature, and light.
• What are biotic factors?

  Living factors in an ecosystem, such as competition, predation, and grazing.
• What is biodiversity?

  The range of different plants and animals living in a particular ecosystem.
• What is a producer?

  An organism that can produce its own food by photosynthesis, such as green plants.
• What is a consumer?

  An organism that eats another organism to obtain food/energy.
• What is a decomposer?

  An organism in the soil that breaks down organic substances, such as bacteria and fungi.
• What is a trophic level?

  The level at which an organism feeds in a food chain.
• What is an autotroph?

  An organism that can produce its own food supply, such as producers.
• What is a heterotroph?


  An organism that obtains food/energy by feeding on other organisms, such as consumers.
• What is the process by which autotrophs produce food?

  • Autotrophs use carbon dioxide from the atmosphere, water from the soil, and light energy from the sun.
  • This process is called photosynthesis.
• Why are producers always at the start of the food chain?

  Because they produce the food for all the other members of the community.
• What do the arrows in a food chain represent?

  The movement of food, the direction of energy flow, and the feeding relationships.
• What are the reasons for short food chains?

  1. Energy is lost between trophic levels.
  2. Only 10% of the energy available to one trophic level is available to the next.
• Why is only 1% of the sun's energy used by plants in photosynthesis?

  Because a lot of light energy is reflected by the atmosphere or is of an unsuitable wavelength for photosynthesis.
• What happens to energy during respiration in animals?

  A lot of energy is lost as heat, which is used to keep warm-blooded animals warm.
• Why is it more efficient for humans to feed on the 2nd trophic level as herbivores?

  Because there is more energy available on the 2nd trophic level than the 3rd, resulting in less energy loss.
• How can farmers maximize the yield from livestock?

  By reducing the amount of energy lost as heat in respiration, such as keeping animals housed indoors.
• What is the estimated total amount of energy flowing through an oak woodland in one year?

  4,600,000 kJ/m²/yr.
• Calculate the percentage of light energy landing on the trees that is stored in the cells of the trees.


  $\frac{44000}{4600000} \times 100 =$$0.96\%$
• Calculate the percentage of energy passed from the producer to the primary consumer.


  $\frac{2900}{44000} \times 100 =$$6.59\%$
• Calculate the percentage of energy passed from the primary consumer to the secondary consumer.


  $\frac{700}{2900} \times 100 =$$24\%$
• Why are food chains with more than three levels uncommon?

  Because energy is lost between trophic levels, limiting the energy available to sustain higher levels.
• What happens to the energy in organisms at the very top of a food chain when they die?

  It is passed to the decomposers.
• What are the differences in energy distribution between herbivores and carnivores?

  • Herbivores have a higher intake of indigestible cellulose fiber.
  • Carnivores are often warm-blooded and have higher respiration rates to generate heat.
• How is energy flow through a food chain more accurately represented?

  Using a pyramid of biomass.
• What is biomass?

  The dry weight of living organisms, excluding water.
• What are the advantages and disadvantages of pyramids of number?

  Advantages:

  • Relatively easy to collect data by counting the number of organisms at each trophic level.

  
  

  Disadvantages:

  • Does not take into account the size of organisms, which can result in inverted pyramids.
• What are the advantages and disadvantages of pyramids of biomass?

  Advantages:

  • Always form the proper shape because energy is lost between trophic levels.
  • Producers will always have the widest bar.

  
  

  Disadvantages:

  • Difficult to measure the biomass of organisms such as trees without destroying them.
• What is the importance of nutrient cycling in ecosystems?

  • Nutrients need to be constantly recycled to provide the atoms needed for new organisms to form.
  • Living organisms obtain matter/atoms/nutrients from the food they eat.
• What are the main elements that living organisms are composed of?

  • Carbon
  • Hydrogen
  • Oxygen
  • Nitrogen
• What happens to carbon atoms during the carbon cycle?

  • CO2 is absorbed by plants during photosynthesis.
  • Some glucose is used in respiration, returning carbon to the atmosphere.
  • Carbon is made available to primary consumers when they eat plants.
• What is the role of decomposers in the ecosystem?

  They break down waste material and dead material, returning nutrients to the soil.
• What is the process by which plants convert CO2 into glucose?

  Photosynthesis.
• How do consumers obtain carbon atoms?

  By consuming plants or other organisms that contain carbon.
• What happens to the glucose produced by plants?

  It can be used for respiration, growth, or stored as starch.