Ecology Flashcards
What is a habitat?
The 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 factors?
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 with the non-living parts of the environment.
Why do animals have to compete to survive?
Animals need to use resources (biotic and abiotic) in order for them to survive they have to get the resources first or they will starve or die, These resources include: - Food, - Drink, - Territory, - Mates.
What is interdependence?
- All species have to depend on each other to live*
- Species need food, if one species died out, the whole ecosystem would be effected as other animals would not be able to get food and also die out etc.
What is a stable community?
When the population of an ecosystem stays roughly constant at all times.
What are examples of abiotic factors (7)?
- Temperature,
- Moisture levels,
- Light intensity,
- Carbon dioxide levels,
- Wind intensity and direction,
- Oxygen levels,
- Soil PH and mineral content.
What are examples of biotic factors (4)?
- New predators,
- Competition,
- New pathogens,
- Availability of food.
What is a change in the environment caused by?
An increase or decrease in abiotic or biotic factors.
Give an example of how an abiotic factor would change the environment?
- A greater light intensity will increase photosynithisis in plants,
- This means plants have more glucose and can grow faster as they need glucose to make energy (respiration) and create proteins for growth,
- Population will increase.
Give an example of how a biotic factor would change the environment?
- If one species dominates the competition for food, they will eat a lot more than other animals,
- This means that other animals will not get enough food and die out,
- This means the predator will eventually die out due to a lack of food.
What are adaptations?
Features or characteristics that organisms have to allow them to live in certain habitats, e.g. Polar bears live in the cold so have thick fur.
What are the three adaptations?
- Structural,
- Behavioural,
- Functional.
What are structural adaptions?
Structural adaptations are features of an organisms body such as shape or colour.
What are some examples of structural adaptations?
- Fur on animals for cold climates.
- Whales have a thick layer of blubber for the cold water/ low surface area to volume ration so heat is kept in better.
- Animals in hot places have thin layers of skin so that heat can be lost easily/ large surface area to volume ratio.
What are behavioural adaptions?
This is the way an animal behaves.
What are some examples of behavioural adaptations?
- Some animals hibernate in winter in order to avoid the cold temperature and the harsher conditions it brings.
What are functional adaptions?
These are internal adaptions that can be related to chemical reactions such as reproduction and metabolism.
What are some examples of functional adaptations?
- Desert animals conserve water by sweating very little and urinating in small concentrated amounts,
- When a brown bear hibernates in winter, their metabolism lowers to conserve energy so they dont have to hunt.
What is an extremophile?
They are organism that are adapted to withstand very extreme conditions.
An example of an extremophile would be microorganisms such as bacteria.
What is a food chain?
It is a diagram that shows what organism is eat by what.
What must all food chains start with?
A producer.
What are some examples of producers?
- algae,
- grass,
- green plants.
What is biomass?
A plant or animals material used for energy production.
How is biomass transferred between organisms?
Eating the organism will take its biomass.
What is the order of a typical food chain?
Producer > Primary consumer > Secondary consumer > Tertiary consumer.
What happens to biomass as you go further up a food chain?
Each organism gives of less biomass because some is lost due to natural circumstances (energy production or movement.)
Where on the food chain is the most biomass typically?
The producers.
Why does the population of prey effect the population of the predators?
- Everyone in an ecosystem are interdependent on each other so the population of all species change when one does.*
- If there is more prey, it means there is more food for the predators, so population increases.
- If the population of the predator increases, then the population of the prey will decrease because more are being eaten.
- If the population of the prey decreases so will the population of the predator because they have less food.
What is the predator-prey cycle?
When the population of the predator changes, so will the population of the prey, and vise versa.
Why is the predator-prey cycle out of phase most the time (There is a delay before the other species’ population changes)?
It takes time for the other species to react to the change in food supply so the population does not change for a short amount of time.
What is the distribution of an organism?
Where the organism can be found. An organism is more likely to live in certain environments because their bodies are better adapted for that environment.
What are the two ways to study distribution of an organism?
- Measure how common a species is in two sample ares (e.g. using quadrats) and compare them,
- Study how the distribution changes across an area, e.g. by placing quadrats along a transect.
What is a quadrat?
A square frame enclosing a known area, used to Compare how common an organism is across two sample areas.
How do you use quadrats to study distribution of an organisms?
- Place a 1m^2 quadrat on the ground in a random spot within the sample area,
- Count all the the organisms within the quadrat,
- Repeat steps 1 and 2 as many times as you can in the sample area,
- Work out the mean number of organisms per quadrat within the first sample area,
- Repeat steps 1 to 4 with the second sample,
compare the two means.
What is a transects?
A single line that is used to sector out an area for studying the distribution of organisms., it can be a tape measure to see the distance that you will be studying.
How do you study the distribution across an area using transect and quadrats?
- Mark out a line in the area you want to study using a tape measure,
- put down quadrats with in the area marked using the tape measure,
- Count the organisms within the quadrat then move down the measuring tape and redo this.
What are three environmental factors that effect the distribution of organisms?
- Availability of water,
- Temperature,
- Atmospheric gases.
How does availability of water effect distribution of organism?
- The distribution of animal and plant species in tropic area changes according to rainfall.
- Some animals and plants like a lot of water while some prefer the lack of water.
How does temperature effect distribution of organism?
- All animals and plants prefer different temperatures.
- For example, European bee-eater bird is now present in parts of Germany instead of their normal Mediterranean habitats.