ecosystems Flashcards
what is a population
a group of organisms of the same species living in the same area at the same time
what is a community
all organisms of all the different species living in the same habitat
what is a habitat
a particular area in which a population lives
name the different types of ecosystems in malta
garigue
maquis
woodland
sand dunes
freshwater
rocky shores
name a few characteristics of garigue ecosystems
-snap pockets of shallow soil
-high sun and heat exposure
-high wind exposure
-low water availability
-Maltese honey bee and blue rock thrush (animals)
-mediterranean thyme,heath and maltese pyramidal orchid (plants)
name a few maquis characteristics
-deep soil
-more water availability, still limited
-relatively sheltered from wind
-hot and dry climate
- lentisk, bay laurel and fig tree (plants)
-maltese wall lizard, maltese rock centipede (animals)
name the characteristics of woodland
-deep soils
-more water availability. still limited
-hot climate
-tall trees
-aleppo pine, Evergreen oak, Olive and carob trees (plants)
-european hedgehog, common black bird (animals)
name some characteristics of sand dunes
-hot and dry climate
-dry sand
-rocks and wind
-high levels of salinity
- sand lizard, sand wasp (animals)
- sand couch, drop seed grass (plants)
name a few characteristics of fresh water
-water temperature
-water PH
-oxygen concentration
-light
-great reed, Maltese waterwork (plants)
-painted frog, maltese freshwater crab (animals)
name a few characteristics of rocky shores
-high winds
-many rock pools
-rough wave action and sea spray
-high levels of salinity
-maltese sea camomile, golden samphire (plants)
-flattened barnacle, black periwinkle (animals)
what is an ecological niche
the way in which an organism interacts with other members of its community and the physical features of its surroundings
name 3 types of local species
indigenous species
endemic species
alien species
what is an indigenous species
a species that naturally occurs in that ecosystem
eg: carob tree found in malta and mediterranean
what is an endemic species
a species which only occurs in one particular area of the world, said to be endemic to that region and doesn’t naturally occur anywhere else, making them vulnerable to extinction
what are alien species
species that have been introduced to an ecosystem that they did not form part of before. These may cause disruptions in the ecosystems and may result in displacement of other species
what is the carrying capacity
the maximum number of individuals if a species that can be supported by the rescources available in a given environment
how can abiotic factors affect a community of organisms
-light intensity (more light more photosynthesis)
-temperature (affects photosynthesis )
- moisture levels (plants and animals need water to survive)
-wind intensity and direction (wind affects transpiration which affects photosynthesis)
what are two important stimuli for plants
light and gravity
what are auxins
hormones that cause plants to react in certain ways, produced at the tips of shoots and roots
what is phototropism
a growth response to light
what is geotropism
a growth response to gravity
phototropism causes :
SHOOT move TOWARDS light
ROOT moves AWAY from light
geotropism causes :
SHOOTS move AWAY from gravity
ROOTS move TOWARDS gravity
what are the main biotic factors affecting communities
availability of food
new predators
competition
new pathogens/parasites
what’s a parasite
an organism that derives its food from another organism called the host, whilst the host is still alive- harming it in the process
what are the two types of parasites
endoparasites- inside host (tapeworms)
ectoparasites- host surface (mosquito)
what is a mutualistic relationship and give an example
a relationship between two organisms that benefits both
eg: insect pollination (bees+flowers)
what do plants usually compete for
-water
-minerals
-space
-light for photosynthesis
what do animals usually compete for
-food to eat
-water to drink
-mates
-territory
explain a predictor pray relationship
the number of predators increases when there is more prey
the number of pray reduces when there are more predators
the number of predators reduces when there is less prey
what are scavengers and decomposers
-scavengers feed on dead parts of organisms and digest it, they help keep the environment clean and reduce chances of disease spread
-decomposers feed on waste material of organisms and on their dead bodies. They break complex materials into simple inorganic substances and make vital nutrients available to ecosystems
