Life on Earth - Biology Revision

• What is a biome?


  A biome is a distinct geographical region with specific climate, vegetation, and animal life.
• What is an ecosystem?


  An ecosystem consists of all the living organisms living in a particular habitat and the non-living components with which the organisms interact.
• Aquatic ecosystem


  An ecosystem in a body of water. Examples: Lakes, ponds, rivers, oceans, and streams
• Terrestrial ecosystem


  An ecosystem that occurs on land. Examples: Tundra, woodland, rainforest ,desert, and grassland.
• Population 


  The total number of individuals from the same species living in one area.
• Community


  Populations of differant species living together in one area. Includes plants and animals.
• Habitat 


  The place an organism lives.
• Species 


  A group of organisms with similar characteristics that can interbreed to produce fertile offspring.
• Biodiversity 


  The total variety and abundance of differant species present in an ecosystem.
• Differant types of biomes.


  Rainforest, temperate forest, taiga, desert, grassland, savanna, tundra, freshwater, and marine.
• Producer

  Example: Grass

  
• Primary consumer

  Prey

  Herbivore

  Example: Grasshopper

  
• Secondary consumer

  Prey

  Predator

  Carnivore/Omnivore

  Example: Small Bird

  
• Tertiary consumer

  Carnivore

  Predator

  Example: Owl

  
• What is a food Web?

  Food Webs show complex feeding relationships with multiple food chains in an ecosystem.
• What is deforestation?


  Deforestation is the cutting down of trees which destroy habitats for animals and reduce biodiversity.
• What is over-fishing?

  Large boats and nets used by fisherman have increased the amount of fish being caught. This has reduced the fish in the ocean. Fishing at a rate that does not allow them enough time to reproduce.
• What is Climate Change?

  Global warming is the continuing rise in the average temperature of our Earth. Increased use/burning of fossil fuels increases greenhouse gases in the atmosphere. Global warming is causing ice to melt and sea levels to rise.
• What is Acid Rain?

  Acid rain is caused by pollution in the air which mixes with water to form acid. Acid rain can run into rivers and cause fish to die.
• Examples of Natural Disasters.

  Forest Fires, earthquakes, tsunamis, floods and volcanic activity.
• How much Nitrogen makes up the air around us?

  70-90%
• Living organisms need nitrogen in order to make protein. True or False?

  True
• What is protein needed for?

  Growth of tissue

  Repair of tissue
• Deficency in humans diets can lead to:

  Stunted growth, weak immune system and loss of muscle.
• Deficency in plants nitrogen/nitrates in soil can cause:

  Stunted growth or inability to grow well. Grow much slower and less yield from crops, less fruit or vegetables or foliage.
• What can be added to soil to add nutrients?

  Fertilisers

  NPK = N= nitrogen

  P= phosphorus

  K= potassium
• Fertilisers

  Provide extra supplies of nitrogen.
• Manure

  Made from faeces and provides the soil with minerals.
• Compost

  Decomposed remains of dead plants to provide the soil with minerals.
• Type of fertilisers.

  Seaweed, coffee, manure, compost.
• Disadvantages of fertiliser

  Water washing chemicals from soil.
• Variation

  Variation is the genetic difference between members of the same species.
• Adaption

  Adaption are inherited characteristics that make an organsim well suited to survive within its environment.
• Types of adaption

  Structural and behavioural
• Introducing new alleles into a gene pool helps what?

  Increase variation within a species.
• Increased variation allows what?

  Species to better adapt to changes in environment. This makes it possible for species to evolve over time.
• Camel adaptations

  Stores fat in humps helping it to survive long periods of time without food and water. Long legs help keep the camel cool.
• Polar bear adaptations

  Thick fur to trap heat. Wide feet to spread their weight over ice and snow.
• Cacti adaptations

  Succulent tissue for storage of water. Spikes on leaves protect the cactus from predators.
• Adaptation of birds beaks

  Each species of bird has a differant shape and size of beak, allowing them to access differant food resources.