Unit 3 - Life on Earth Flashcards
The variety of life forms in a particular area
Biodiversity
Living factors that affect biodiversity
Biotic factors
Non-living factors that affect biodiversity
Abiotic factors
Examples of biotic factors
Predation OR Grazing OR Food availability OR Disease
Examples of abiotic factors
Temperature OR Light intensity OR pH OR Oxygen concentration
All the living and non living factors in an area
Ecosystem
The place an organism lives
Habitat
Regions of the planet with similar climates, animals and plants
Biome
Main influences determining the distribution of biomes
Temperature and rainfall
ALL the organisms living in an area
community
The role an organism plays within a community
Niche
Result of two organisms that need the same resource (food)
Competition
Type of competition between members of SAME species
Intraspecific
Type of competition between members of DIFFERENT species
Interspecific
Examples of resources which organisms compete for
Food OR Light OR Water OR Space
A relationship between animals in which on hunts and kills the other
Predation
A relationship between two organisms in which one benefits and the other is harmed
Parasitism
Percentage of energy lost at each level of a food chain
90%
Percentage of energy in food used for growth
10%
Ways in which energy is lost from each level in a food chain
Heat OR Movement OR Undigested food
A diagram with the width of each
bar representing the NUMBER of
organisms at that feeding level in a
food chain
Pyramid of numbers
A diagram representing the total
energy contained in the organisms
at each feeding level
Pyramid of energy
Organism that makes its own food by photosynthesis
Producer
Organism that has to eat another organism to obtain energy
Consumer
A plant eating organism
Herbivore
An organism that eats both animals and plants
Omnivore
An organism that eats animals
Carnivore
All the organisms of ONE SPECIES living in an area
Population
Molecule produced by plants using nitrogen from nitrates
Protein
Example of a decomposer
Bacteria
OR
Fungi
Man made nitrates use by farmers to increase crop yields
Fertilisers
A method for sampling ground living insects/invertebrates
Pitfall trap
A square placed on the ground to estimate number of plants
Quadrat
Ways to reduce errors with sampling in quadrats and pitfall traps
Place randomly
OR
Take many samples
Why do we repeat sampling
To increase reliability
Instrument to measure pH of soil
pH meter
Instrument to measure moisture of soil
moisture meter
Instrument to measure air temperature
thermometer
Ways to minimise error when using probes
Wipe between samples
Name for random changes to DNA/Genetic material
Mutation
Environmental factors that increase rate of mutation
Radiation OR UV light OR X-rays OR Some chemicals
Differences in members of a species
Variation
Inherited characteristic that makes and organism suited to survive in its environment
Adaptation
Biological term for a group of organisms that can interbreed and produce fertile offspring
Species
Term for an organism that is best adapted to its environment and passes on favourable genes/alleles to offspring
Natural selection
The process by which a new species can arise after isolation from part of a population
Speciation
A reason for different alleles arising in two isolated populations
Mutations will occur in each population
Term for gradual change in genetic makeup over many generations
Evolution
Types of speciation barrier that may separate a population
Geographical (river/mountains) OR Reproductive (different mating displays) OR Ecological (plants prefer different light intensities)
Effect of excess fertiliser leaching into fresh water
Eutrophication
OR
Algal bloom
Effect of algal bloom on biodiversity
Plant and animal species will decrease due to decrease in light and oxygen
Man made chemical used to kill of pests
Pesticides
Herbicides/insecticides/fungicides
Use of natural predator to reduce or limit the number of pests
Biological control
Plants that have gene inserted to protect against pests OR increase crop size
Genetically modified
What is the waste product of water splitting?
Oxygen (released from stomata)
Second stage of photosynthesis
Carbon fixation
Controls the series of reactions in photosynthesis
Enzymes
Produced by water splitting and combines with Carbon Dioxide to make glucose
Hydrogen
Product of photosynthesis that can be used in respiration or converted to other molecules
Glucose
Structural molecule used to make cell walls
Cellulose
Storage carbohydrate in plants
Starch
Word equation for photosynthesis
Carbon dioxide + Water -> Glucose + Oxygen
Term for an essential input in short supply that reduces the rate of photosynthesis
Limiting factor
Limiting factor on a cloudy day in summer
Light intensity
Limiting factor on a sunny day in winter
Temperature
Three factors that may limit the speed / rate of photosynthesis
Temperature, Light intensity, Carbon dioxide concentration
