B7 Flashcards
Habitat?
the environment in which an organism lives e.g. elephants live in grasslands
Population?
Total number of organisms of the same species living in the same geographical area
Community?
The populations of all the different species that live in the same habitat
Biotic?
living
Ecosystem?
both the biotic and the abiotic parts of an environment and how they interact
Why do living organisms have to compete with each other?
because there is only a short supply of resources such as food and water
4 things that plants compete for?
light
space
water
mineral ions from the soil
What 2 things do animals compete for?
Food
Water
Why do animals compete for food and water?
for mating partners and territory
Interdependence?
All of the different species in a community depend on each other
e.g. lions eat animals such as zebras and gazelles
e.g. zebras and gazelles eat grass and shrubs
Why do animals depend on trees?
they provide shelter from the sun
how do plants depend on animals?
Many plants depend on bees to spread their pollen
How could losing one part of an of an ecosystem affect other animals?
for example, if all plants died, then there would be no food for zebras and gazelles leading to the population falling
Stable community?
In most communities, the populations of the different species remain fairly constant
abiotic?
non-living parts on an ecosystem e.g. water, light intensity, temperature
what are the four different biotic factors?
availability of food e.g. lions eat zebras
Arrival of a new predator species - can cause the population of a prey species to fall
competition - if a species is outcompeted then its population can fall so much that they could go extinct
New pathogens - if an infectious disease spreads it can wipe out a population of species
What are the first 2 abiotic factors?
Light intensity - all plants need life to carry out photosynthesis
Temperature - Animals could migrate away from the hot area and plants could disappear, water evaporation
Next two abiotic factors?
Wind intensity and direction - strong winds blowing inland from the sea can cause plants to lose water
carbon dioxide and oxygen - carbon dioxide is needed for photosynthesis and if these levels fall, then the rate of photosynthesis decreases, oxygen is needed for aerobic respiration
4 structural adaptations of camels to the hot and dry conditions of a desert?
humps - store fat in one place, which allows heat loss from other parts of the body and reduces water loss from sweating
Thick coat on the upper surface - insulates the top of the camel from the heat of the sun
Leathery mouth - able to chew plants which have thorns
Long eyelashes - keep dust out of the eyes
2 functional adaptations of camels to the hot and dry desert?
They produce concentrated urine and dry faeces to reduce water loss
can tolerate very large changes in body temperature
behavioural adaptation of a kangaroo rat?
nocturnal, this avoids the heat of the desert, and during the day they live in burrows underground to keep them cool and away from predators