B7-Ecology

• What is a habitat?


  Place where an organism lives
• What is a population?

  All the organisms of one species living in a habitat
• What is a community?

  The populations of different species living in a habitat
• What are abiotic


  non-living factors of the environment e.g. temperature
• What are biotic factors?

  living factors of the environment e.g. food
• What is an ecosystem?

  The interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment
• How do plants and animals compete for resources to survive?

  -Organisms need things from their environment and from other organisms in order for survival and reproduce:

  -Plants-need light and space, as well as water and mineral ions from the soil.

  -Animals needs space (territory),food, water and mates.

  -Organisms compete with other organisms for the same resources.
• What is interdependence?


  In a community, each species depends on other species for things such as food, shelter, pollination and seed dispersal.
• What does interdependence mean?


  The interdependence of all living things in an eco-system means that any major changes in the ecosystem (such as one species being removed) can have far-reaching effects.
• What is the effect on the population in changes to the environment?

  -Less competition-population increase

  -More likely to be eaten by predators-decrease

  -Less food-decrease
• What is a stable community?


  A community is one where all the species and environmental factors are in balance so that the population sizes remain fairly constant.

  Examples-tropical rainforests and ancient oak woodlands.
• What are the different abiotic factors in an ecosystem?

  -moisture levels

  -light intensity

  -temperature

  -carbon dioxide level

  -wind intensity and direction

  -oxygen level

  -soil ph and mineral content
• How can a change in environment affect the community?

  -Increase or decrease in an abiotic factor e.g an increase in temp.

  -These changes can affect the size of populations in a community.
• How can a decrease in light intensity, temperature or level of carbon dioxide affect a community?

  -Decreases the rate of photosynthesis in a plant species.

  -Could affect a plants growth and cause a decrease in population size.
• How can a decrease in mineral content in soil affect a community?

  -Could cause nutrient deficiencies.

  -Could also affect plant growth and cause a decrease in the population size.
• What are examples of biotic factors?

  -New predators

  -Competition

  -New pathogens

  -Availability of food
• What can a change in environment cause?

  -could be the introduction of a new biotic factor e.g new predators or pathogen.

  -changes could also affect the size of the population in a community which can have knock on effects because of interdependence.
• How do adaptations help an animal?


  Allow organisms to survive.

  Organisms including microorganisms are adapted to live in different environmental conditions-The features and characteristics that allow them to do this are called adaptations.
• What are the different types of adaptations?

  structural, behavioral, functional
• What are structural adaptations and what are some examples?

  Features of an organisms body structure-shape or colour.

  -Artic animals-have white fur so they're camouflaged against the snow.This helps them avoid predators and sneak up on prey.

  -Animals that live in cold environments-have a thick layer of blubber and a low surface area to volume ratio to help them retain heat.

  -Animals that live in hot places (like camels) have a thin layer of fat and a large surface area to volume ratio to help them lose heat.
• What are behavioural adaptations and what is an example of this?

  -These are ways that organisms behave.

  -Many species (e.g. swallows) migrate to warmer climates during the winter to avoid the problems of living in cold conditions.
• What are functional adaptations and what is an example of this?

  Things that go on inside an organism's body that can be related to processes like reproduction & metabolism.

  1)Desert animals conserve water by producing very little sweat and small amounts of concentrated urine

  2)Brown bears hibernate over winter.They over their metabolism which conserves energy's they don't have to hunt when there is not much food about.
• What are extra


  Organisms that can live in extreme conditions such as high pressure, high salt concentration, or high temperatures
• What do food chains start with?

  Producer
• What is a producer?

  -Producers make their own food using energy from the Sun.

  -Producers are usually green plant or algae-they make glucose by photosynthesis.

  -When a green plant produces glucose, some of it is used to make other biological molecules in the plant.
• What re the biological molecules known as?

  -Biomass

  -the mass of living material

  Biomass can be thought of as an energy stored in a plant.
• How is energy transferred through living organisms?

  When organisms eat other organisms
• What is the chain further from producers?

  Producers are eaten by primary consumers.

  Primary consumers-then eaten by secondary consumers and secondary consumers are eaten by tertiary consumers.
• How do the population of predators and prey correlate?

  In a stable community containing prey and predators)

  1)the population of any species is usually limited by the amount of food available.

  2)If the population of the the prey increases, then so will the population of the predators

  3)However ,as the population of predators increases, the number of prey will decrease.
• How are predator prey cycles described?

  -always out of phase with one another

  -this is because it takes a while for one population to respond to changes in the other population.

  e.g when the number of rabbits goes up,the number of foxes doesn't increase immediately because it takes time for them to reproduce.
• What are the two ways in which we can study the distribution of an organism?

  -Measure how common an organism is in two sample areas (using quadrants and comparing them)

  -Study how the distribution changes across an area

  (by placing the quadrants along a transect

  Both give quantitative data about the distribution
• Describe a method to use quadrants to study the distribution of small organisms

  A quadrant is a square frame enclosing a known area.

  1)Place a 1m squared quadrat on the ground at a. random point within the first sample area.(Divide the area into a grid and use a random number generator to pick coordinates.

  2)Count all the organisms within the quadrat

  3)Repeat steps 1 and 2 as many time as you can

  4)Work out the mean number of organisms per quadrat by adding total umber of organisms and dividing it by the number of quadrats.

  5)Repeat steps 1-4 in the second sample area.
• Describe a method of using transects to study the distribution of organisms along a line


  1)Mark out a line in the area you want to study using a tape measurer

  2)Collect data along the line

  3)You can do this by just counting all the organisms you are interested in that touch the line.

  4)Or we can add quadrants along the transect line
• Describe the water cycle

  1)Energy from the Sun makes water evaporate from the land and sea, turning it into water vapour

  2)water also evaporates from plants by the process of transpiration

  3)The warm water vapour is carried upwards.When it gets higher up, it cools and condenses to from clouds.

  4)Water falls from the clouds as precipitation (usually rain, sometimes snow or hail) onto land, where it provides fresh water for plants and animals

  5)Some of this water is absorbed by the soil and is taken up by the plant roots.This provides plants with fresh water for things like photosynthesis.Some of the water is taken up by plants, becomes part of the plants tissues and is passed along to animals in food chains.

  6)Like plants, animals need water for the chemical reactions that happen in their body.Animals therefore return the water to the soil and atmosphere through secretion.

  7)Water that does not get absorbed by the soil will run off into streams and rivers.

  8)From here, the water then drains back into the sea, before it evaporates all over again.
• What are living things made out of?

  Made of materials they take from the world around them.

  Plants turn elements like carbon, nitrogen, oxygen and hydrogen into complex compounds that make up living organisms.THESE GET PASSED THROUGHOUT THE FOOD CHAIN.
• How are the materials returned back tot he environment?

  In waste products

  or when the organisms die and decay
• How do materials decay?

  Because they're broken down by microorganisms.

  Decay puts the stuff that plants need to grow back into he soil.
• How does decay happen faster?

  In moist and aerobic conditions because microorganisms are more active in these conditions.
• Describe the carbon cycle (7 points)

  1) Carbon dioxide is removed by the atmosphere by green plants and algae during photosynthesis.The carbon is used to make glucose which can be turned into carbohydrates, fats and proteins that make up the bodies of the plants and algae.

  2 )When plants and algae respire-some carbon is returned to the atmosphere as CO2

  3) When plants and algae are eaten by animals, some carbon becomes part of the fats and proteins in their bodies.The carbon then moved through the food chain.

  4) When animals respire, some carbon is returned to the atmosphere as CO2.

  5) When plants, algae and animals die, other organisms and microorganisms feed go their remains.When these organs respire, Co2 is returned to the atmosphere.

  6) Animals also produce waste that is broken down by detritus feeders and micro-organisms.

  7) The combustion of wood and fossil fuels also release Co2 back into the air
• What is biodiversity?


  Biodiversity is the variety of different species of organisms on Earth, or within an ecosystem