Adaptations, interdependence and competition.

Define interdependence

The network of relationships between different organisms within a community.

Define ecosystem.

The community of organisms interacting with the non-living and living factors of their environemtent.

Define community.

A group of interdependent living organisms in an ecosystem.

Define population.

A group of organisms of the same species living in a habitat.

Give examples of how plants and animals can interact in an ecosystem.

Plants produce food by photosynthesis

Animals eat plants

Animals pollinate plants

Animals eat other animals

What is a stable community?

Where the environmental factors are relatively constant.

The species of living organisms are in balance.

Describe several examples of stable communities.

Tropical rainforest

Oak woodlands

Mature coral reefs

What are stable communities important?

They take a long time to evolve and aren't easily replaced.

They include a high range of biodiversity.

Biotics factors: describe food availability.

When there is an abundance of food, organisms breed successfully.

A lack of food means animals struggle to survive and don't breed.

Biotics factors: describe predators

New predators arriving may mean organisms have no defense against them and quickly wiped out.

Biotics factors: describe diseases

When a new pathogen or parasite emerges, organisms have no resistance to the disease.

They can damage or wipe out populations in a community.

Biotics factors: describe competition for resources between species

Interspecific competition (competition between different species): a new species may outcompete another to the point where members become too low for successful breeding.

Abiotic factors: describe temperature

A limiting factor phor photosynthesis

Warmer tempertatures means plants photosynthesis faster and grow faster and bigger.

If more plants grow, there are more foods for animals, so animals populations increase.

Describe examples of abiotics factors.

Amount of rainfall

Light intensity

Soil pH

Mineral content of soil

Temperature

Oxygen levels

CO2 levels.

Abiotic factors: describe soil pH

Affects the rate of decay and controls the release of mineral ions back nto the soil.

Acidic pHs inhibits decay and therefore reduces the number of plant species that can grow.

If more plants grow, more food for animals so populations increase.

Abiotic factors: describe soil minerals

If more nitrate ions, there is increased plant growth as can make amoni acids for proteins.

If more magnesium ions, there is increased plant growth as more chlorophyll for photosynthesis.

If low mineral content, there are fewer plants, although some have adapted to growing in poor mineral areas by trapping and digesting animals.

If there are more minerals there is more food for animals so their populations increase.

Abiotic factors: describe light intensity

Limiting factor for photosynthesis: increased light intensity means plants photosynthesise faster so grow faster.

Means more food if there are more plants so bigger animals productions.

Abiotic factors: describe the availability of water.

If not enough water, then no plants grow.

If the correct level, then plants grow better.

If now water, animals will die. If correct level, more food as more plants.

Abiotic factors: describe availability of oxygen.

Oxygen levels not usually limiting, but if more animals, more predation by herbivores.

In most cases, if higher oxygen levels, more animals can grow. More food as more plants.

Abiotic factors: describe the availability of CO2.

Limiting factor for photosynthesis.

Increasing CO2 levels means plants photosynthesise faster so grow faster and bigger.

Some blood suching insects are attracted to carbon dioxide.

Also more food for animals as more plants.

Measuring abiotics factors. Describe how to measure rainfall.

Use a rain gauge the same time every morning (24 hour period) between data collection.

The rain gauge is a funnel that empties into a bottle. These are poured into a measuring cylinder and the depth of rainfall in mm is calculated.

Measuring abiotics factors. Describe how to measure temperature.

Using a thermometer, in degrees celsius.

Measured it at any time of day.

Didital thermometer: connects to a data logged that records the temperature, usually via graphical output.

An advantage is that nobody needs to actually be present to take the reading. Better resolution. Equipment is expensive.

Maximum-minimum thermometer: not as expensive, have to be there to collect data, lower reolution.

Measuring abiotics factors. Describe how to measure oxygen levels.

Using a digital oxygen probe, connects to a data logged and records oxygen levels automatically over time.

Unit is % or parts per million (ppm).

Can be measured at any point or continuously.

What is competition?

An interaction between organisms or species in which both require a resource that's in limited supply.

What may animals compete for?

Mates - animals competer through physical contact (eg tusks) or display/rituals (bright fathers)

Food - may be in limited supply

Territory - some areas are safer to raise offspring from predators, better access to food

What may plants compete for?

Seed dispersion - allows species to spread and makes it harder for diseases and pests to spread.

Light

Water

Nutrients

Describe the phases of predator prey graphs.

Lag phase - organisms adapting to their environment

Log phase - large increase in population as resources are plentiful

Stationary phase - some resources become limiting so population stops increasing - brth and death rates are eaqual

Death phase - poth populations fall as resources may run out completely or toxic waste products build up.

What is a predator?

Animals that kill and eat other animals.

What are prey?

The animals eaten by predators.

What is an extremophile?

AN ORGANISM THAT CAN SURVIVE AND REPRODUCE IN VERY EXTREME CONDITIONS.

Example of extremophile: describe thermophiles

Types of bacteria known as thermophiles which can survive at temperatures of over 45 degrees and often up to 80 degrees plus.

Have specially adapted enzymes that don't denature at these high temperatures.

Many cant lsurvive at lower temperatures.

Example of extremophile: describe bacteria in salty environments.

Some bacteria can live in extremely salty environments like the Dead Sea and salt flats.

These bacteria have adaptations to their cytoplasm so that water doesn't move out into the salty water by osmosis.

Describe the adaptations of the arctic fox.

White fur to camouflage with snow and hide from predators.

Largy fluffy predator to act as insulation and provides warmth when the fox sleeps.

Describe the adaptations of the arctic hare.

Fur is white during winter to blend with snow.

Turns greyish-brown during summer to blend with environment.

Ong curved claws for digging into hard packed snow.

Describe the adaptations of the (desert) fennec fox.

Golden fur to blend with sand and hide from predators.

Small, so little food and water needed to survive.

Big ears allows heat to escape from body, keeping it cool. A good blood supply to the ears allows for more heat loss via radiation. Gives them great sense of hearing to watch out for predators.

Nocturnal to avoid hunting in warm day temperatures and reduces risk of dehydration.

Describe where the fennec fox is found

Sandy deserts in North Africa

Extreme heat during the day and very cold temperatures at night

Andy dunes, rocky terrains, sparse vegetation and few water sources.

Describe the habitat of a polar bear.

Arctic and tundra environment.

Extreme long, cold waters.

The sea ice is important as the polar bears main prey, seals, live on these platforms.

Describe the adaptations of a polar bear.

Large SA:V reducing heat loss

Sarp teeth and claws allowing them to tear into the thick blubber of seals.

Thick layer of fat provides insulation against the cold and acts as an energy store during scarce food supplies.

Beneath fur they have black skin which absorbs heat from the sun for warmth

Large wide flat feet to distribute weight

Describe where the saguaro cactus is found.

The Sonoran desert in the southwestern US and northern Mexico.

Ctremely dry, high winds, intense heat and little rainfall.

How is the saguaro cactus adapted?

Stem - fleshy stem stores large amounts of water, allowing it to survive long periods of drought. Waxy coating that reduces water loss via evaporation.

Leaves - chlorophyll is found in the stem allowing the plant to carry out photosynthesis.

Large white flowers in late spring that bloom at night and early morning to avoid heat of the day.

Shallow widespread roots o allow the cactus to quickly absorb water before it evaporates.