Biology paper 2 (Ecology) Flashcards
what is the main thing to understand in ecology
All organisms have relationships with animals that live near them and the environment for example these animals can breathe in oxygen and breath out CO2 and can also burrow holes in the soil to improve irrigation and improve quality of the soil. Meaning that if one part of the ecosystem were to change then the other parts of the ecosystem are likely to be affected
what does habitat mean
habitat is where an organism lives
what is the population
the population is all the organisms of a particular species that live together in that habitat
what is the community
the community is all the populations of different species that live together in that habitat
what is the ecosystem
the ecosystem refers to the interaction of a community of living species with non - living parts of their environment
what do animals and plants compete for
animals compete for territory, mates and food
plants compete for light water(mineral ions) space, soil
what does interdependence mean
interdependence is the thought that all species depend on other species in some way
what are biotic factors and examples of them
Biotic factors are any living factors of the environment that affects an organism or shapes the ecosystem in some way or another
for example:
- competition for different resources and habitat
- amount of disease
- availability for food
what are abiotic factors and examples of them
Abiotic factors are non living parts of the environment that affects an organism or shapes the ecosystem in some way
- wind intensity/direction
- light intensity
- moisture levels
- temperature
- CO2 and O2 levels
- PH level and mineral content of the soil
give two examples of plant adaptations
- plants that grow deep roots can access underground water easier than those plants that grow shallow roots
- plants can spread their seeds across wide areas to reduce competition among themselves
how can we plan an investigation for plant competition
- set up two trays of cress seeds
- compact seeds in one tray and spread out seeds in other tray
- leave all other conditions identical to each other
- after a few days record differences in growth in each tray of seedlings
what do organisms need in order to survive and reproduce
in order to survive and reproduce organisms require a supply of materials from their surroundings and from other living organisms in their common habitat
what are adaptations and what do they allow
adaptations are special features of an organism that allow that organism to survive in particular habitats even when conditions are extreme
what are extremophiles
extremophiles are organisms usually microorganisms that are adapted to survive in conditions where most enzymes wouldn’t work as they regularly would denature
describe some adaptations in animals
adaptations can either be structural ( physical ) behavioural or functional (inside processes) that enable these organisms to survive in conditions specific to that animal
- one way animals have adapted in cold climates is to have thick fur and also fat under skin in other words blubber to conserve heat and keep organism warm
- animals in the arctic such as the artic fox are adapted to remain white in winter and brown in summer to maintain camouflaged so that hunting prey or in other cases hiding from predators is easier
- bigger animals have a lower surface area to volume ratio then smaller animals. This means that in bigger animals conserving energy/heat energy is easier however it also means that cooling down is made difficult.
- in hot and dry conditions animals are adapted to conserve water and not get to hot. Some animals have developed behavioural adaptations as those in the dessert may hunt or feed during the night to remain cool during the day
what is an example of a defence mechanism
some animals such as caterpillar’s are poisonous and such have warning colours to fend and scare of predators to prevent them from being eaten
explain adaptations within plants
a plant needs to collect and conserve water however water is lost from the plant in the form of water vapour through the stomata in the leaves and therefore has developed adaptations to reduce water loss as follow
- closing of the stomata at certain times but especially in hot climates seen as rate of evaporation would be highest at these times to reduce water loss
- fewer stomata as if there is fewer stomata then less water is lost
- plants have adapted to have waxy cuticles which act as waterproof barriers in which decreases rate of transpiration (water lost through leaves) by preventation of evaporation
- plants have also adapted to have an extensive root system which enables them to collect water in a dry environment
- plants have also adapted to have swollen stems to store and conserve water acting as a method in a way to reduce water loss
- plants have also adapted to develop thorns, poisonous chemicals, and warning colours to prevent them from being eaten
describe food chains
feeding relationships within a community can be represented by food chains starting with a producer that is a photosynthetic organism that is responsible for producing biomass on earth and these producers are commonly algae or green plants that get their main source of energy from the sun needed for photosynthesis. The glucose then produced via the process of photosynthesis can be used to synthesise other compounds such as plant cells. A producer is then consumed by the primary consumer however as cellulose from algae and green plants is difficult to digest consumers must eat lots of plant material in order to absorb sufficient amounts of nutrients. A stable community is one in which populations (numbers) of predators and prey rise and fall in cycles
how does material cycling work (talk about why its important)
materials will cycle between abiotic and biotic components of the ecosystem. The recycling of these materials back into the environment is very important as it provides building bocks for future organisms.
First plant material is ate by consumers then through the process of excretion faeces and urine and potentially dead organisms is given of as waste products
detritus feeders or sometimes referred to as detritivores for example maggots and worms can induce decaying process by eating remains of dead organisms and waste products
decomposers such as bacteria and fungi will digest and break down dead organisms and waste products releasing carbon dioxide back into the air which can be absorbed by the plants/trees via photosynthesis which its glucose produced can be used to synthesise other compounds such as plant cells. Also mineral ions and water will be secreted back into the soil and absorbed into the plant via the roots and the process of material cycling event can repeat once more.
