Science Y2

• What is a habitat?

  A place where organisms live
• What is a population?


  Organisms of the same species that live in a particular habitat
• What is a community in ecological terms?

  Made up of different plant and animal populations living together and interacting in a habitat
• What is an ecosystem?

  The interactions between a community and its physical environment
• What are the components of the physical environment in a habitat?

  • Sunlight
  • Temperature
  • Water
  • Air
  • Minerals
  • pH
• What constitutes the biotic environment in a habitat?

  • All the organisms/biotic factors in a habitat
• How do abiotic factors influence biotic factors in an environment?

  The abiotic factors in the environment determine the type of biotic factors that can live in that environment
• What happens to biotic factors that cannot adapt to abiotic factors?


  They will not survive in that environment
• What are adaptations in organisms?

  • Physical or behavioral characteristics developed over time
  • Help organisms survive better in their environment
  • Can be structural or behavioral

  
• What are structural adaptations?

  • Physical features that protect from enemies or warn predators
  • Examples: sharp spikes, blue and yellow colors
  • Features to feed or find food, like downward-facing mouths
  • Features to gain sufficient oxygen, like breathing roots

  
• What are behavioral adaptations?

  • Ways an organism behaves to protect from predators
  • Examples: hiding in sea anemone tentacles, gliding from tree to tree, migrating to escape cold weather
• What are the benefits of adaptations?

  • Enable organisms to find food
  • Help escape from predators
  • Attract mates
  • Allow survival in environmental conditions
• What happens if an organism is unable to adapt?

  It may face extinction
• Why does adaptation require a long period of time?

  Because when the environment changes too quickly, species do not have enough time to adapt
• What is the predator-prey relationship?


  • Predators hunt and kill other animals for food
  • Animals killed are called prey
  • Predators are adapted to catch prey with good senses, speed, strong jaws, claws, and camouflage
  • Prey have adaptations like camouflage, high speed, and small size to protect themselves

  
• What is mutualism?

  • A relationship between two or more organisms in which both benefit
• What is parasitism?

  • A relationship in which one organism benefits while the other is harmed
  • The organism causing harm is called a parasite
• What are the trophic levels in a food chain?

  • Producers
  • Primary consumers
  • Secondary consumers
• What happens to energy as it is transferred from one trophic level to another?

  Energy is lost to the environment
• How is energy lost in a food chain?


  • As thermal energy during respiration
  • In uneaten body parts
  • Through undigested matter egested by consumers
  • Through waste products excreted by consumers
  • Used for body movement (only for primary and secondary consumers)

  
• What percentage of energy is lost from one trophic level to the next?

  90%
• What happens to the predator and prey populations in an ecosystem?

  A rise in predator population causes more prey to be eaten, leading to a decline in prey population
• What occurs when a predator is removed from an ecosystem?

  The prey population will rise but eventually fall since it cannot be supported by producers
• What is the pyramid of numbers?

  • It can be inverted when many small organisms feed on a large organism
  • Example: Many small caterpillars feed on one large tree
• What is the pyramid of biomass?


  • Remains broad at the bottom as one large organism has a comparatively large biomass
  • Represents biomass at a snapshot of time
  • Does not account for the rate of reproduction of organisms
• What is work in physics?

  The use of a force to move an object in the direction of the force
• What is the formula for work done?

  $W =$$F \times d$
• What are the SI units for work?

  Joules
• What conditions are required for work to be done?


  There must be force acting on the object, the object must move through a distance, and the object must move in the direction of the force

  
• When is work not done?

  When any of the three conditions are not fulfilled
• What is energy?


  The ability to do work
• What are the different forms of energy?

  • Potential energy (PE)
  • Kinetic energy (KE)
  • Electrical energy (EE)
  • Thermal energy (TE)
  • Light energy (LE)
  • Sound energy (SE)
  • Nuclear energy (NE)
• What happens when work is done?

  Energy is transferred from one object to another
• What is potential energy?

  • Stored energy due to a body’s position or condition
  • Depends on height, mass, and gravitational field strength
• What is the formula for gravitational potential energy?


  $GPE =$$mgh$
• What factors affect gravitational potential energy?


  Height, mass, and gravitational field strength
• What is kinetic energy?


  The energy that a body has due to its motion
• What is the formula for kinetic energy?


  $KE =$$\frac{1}{2}mv^2$
• What happens to thermal energy as friction increases?

  Thermal energy increases
• What is total mechanical energy?

  • The sum of potential energy and kinetic energy