science year 9 chp 9 ecosystems Flashcards
what is ecology
the study of how organisms interact (affect) with each other and with their non living surroundings. they are also study environments and factors that affect survival of organisms.
what is an ecosystem
is a place where the organisms and their physical surroundings form an environment that is different from other environments nearby
Organisms in an ecosystem are affected by two sets of environmental factors - what are they
ABIOTIC: Physical factors eg sunlight, rainfall, fires, wind
BIOTIC: Living factors such as predators, infectious bacteria, viruses and also included dead organisms eg rotting logs faeces and urine
Abiotic Factor: WATER
essential for all organisms and allows chemical reactions to occur. Water allows the movement of chemcials within the cell without this the cell would die
.Animals in desert with access to less water are nocturnal
Abiotic Factor: Temperature
temp affects the speed of chemical reactions in the cell. As temp increases the rate of reaction increases to. Fish Lizards are ECOTHERMIC meaning to obtain heat from their environment, therefore their body temp varies depending on the environment. These animals will regulate their temp by lying on rocks.
ENDOTHERMIC means warm blooded and can generate heat internally keeping body temp constant eg mammals, humans, kangaroos
Abiotic Factor: Fire
Some fires can kill plants but others flower better and drop their seed after a fire. Plants germinate after a fire in response to chemicals released in fire
Abiotic Factor: Light
Light is necessary for Photosynthesis
Change in light will affect growth rate of plants, this is why in winter the growth rate of plants is much slower as there is less light. Light can also affect animal behaviour eg rock lobster avoid bright moonlight
What is Photosynthesis
process by which plants manufacture their food materials using water, carbon dioxide and light
Is Ecothermic cold or warm blooded
cold Endothermic (warm)
Abiotic factor: soil type
Most plants require nitrate and phosphate. Loam soil usually contains more plant nutrients than sandy soil. The chemical composition of soil will determine what plants can grow there
Abiotic factor: oxygen
most organisms require oxygen to carry out respiration (this provides the cells with energy). Amount of water in oxygen depends on temp, movement and depth
What is interdependence
means that all organisms in a food web are interconnected and affecting each others survival in helpful and harmful ways.
What is an community
all the living things in an ecosystem
When are organisms in competition
when they both try to obtain the same resource, which may only exist in limited amounts
Define prey, predator and predation
Prey is the one being eaten
Predator is the attacker
The feeding relationship is the predation
Give examples of Biotic Factors
Competition, predation, mutualism, parasitism, adaptationism
What is Mutualism
is a relationship where two organisms live closely together and both benefit. eg a cleaner shrimp and a fish
What is Parasitism
Is a relationship when one organism benefits from the relationship and the other is harmed. eg wasp on a caterpillar
What factors affect population size in an area
birth rate, death rate, immigration and emigration
What is an adaptation
any feature that assists an organism to survive and reproduce in its environments
Adaptations are divided into groups what are they and give examples
STRUCTURAL: the wing of a bat
BEHAVIOURAL: bats using echolocation
FUNCTIONAL: bats hearts beats faster when they fly
What is sustainability
means that an ecosystem has the ability to maintain suitable living conditions for the community
things such as water / nitrogen for growth, sunlight for energy, wide range of species and food.
What are producer and consumers
Producers are a source of food most likely green plant. A consumer uses the food source provided by the producer
draw the photosynthesis equation
sunlight
carbon dioxide + water —————->glucose + oxygen
chlorophyll
what is a food chain
is a diagram showing the sequence of organism feeding on each other. Draw an example
What is a food web
there are many food chains within a community. It is all the food chains interconnected that form a food web
What are decomposers
organisms that break down dead bodies and waste and recycle matter for the producers to reuse. Eg are bacteria and fungi
What is pyramids of energy
the energy losses along a food chain can be represented in a diagram called a pyramid of energy.
Draw an example
What is Biodiversity
the number of different species in an ecosystem and the population of each of these species
name 4 reasons for protecting ecosystems
1 cultural value - speicies have a value as part of the way of life of a country eg kangaroo
2 economics - some plants and animals have a financial value eg great barrier reef
3 survival - we get oxygen water food from the environment around us
4 compassion - humans feeling sympathy for other organism eg stranded whale
Name natural events that can affect ecosystems
Bushfires
Drought
Flooding
Name changes on ecosystem due to human impacts
Habitat destruction CLEARING Introduced species CAT FOX Chemical Pesticides DDT Chemical Pollution OIL SPILL Over cropping WHALING
