Life on Earth

What is an ecosystem?

It consists of all the organisms living in a particular habitat

What is a species?

An organism that can interbreed to product fertile offsprings

What is biodiversity?

It’s the range of living things in an ecosystem

What is population?

It’s the total number of a single species in an ecosystem

What is the definition of community?

All of the organisms living in an ecosystem

What is the definition of a producer?

Is the plant that being the food chain by making their own energy

What is a consumer?

An orangish that must consume other organisms to gain energy to survive

What the definition of a herbivore?

An organism that only eats plant

What’s a carnivore?

An organism that only eats animals

What is an omnivore?

An organism that eats both plant and animals

What is the definition of a predator?

It’s an organism the hunts, kills and eats other animals for food

What the definition of a prey?

An organism that predators kills for food

What the definition of a niche?

The role an organism play in its community

When does interspecific competition occur?

It occurs amongst individuals of DIFFERENT species for a few of the resources the both require

When does intraspecific occur?

Occurs amongst individuals of the SAME species and is for ALL resources required

What competition is more intense interspecific or inraspecific?

Intraspeific

What the definition of a biotic factor?

Their living factors the affect the distribution of organism

What is the definition of an abiotic factor?

Their non-living factors affect the distribution of organisms

What is an indicator species?

They’re species the by there absent or present can indicate the level of pollution

What is the photosynthesis word equation?

Carbon dioxide + water ——light energy + chlorophyll——> glucose + oxygen

What is photosynthesis?

It’s the process by which green plant make their own food

What are the stages called in photosynthesis?

Stage 1 - Light dependent stage

Stage 2 - Carbon fixation

What is the definition of stage 1 of photosynthesis?

It’s the light energy from the sun then is trapped by the chlorophyll in the chloroplasts and is converted into chemical energy with is used to generate ATP

What is water split into?

It’s split in to hydrogen and oxygen

What is the definition of stage 2 of photosynthesis?

It’s the series of enzyme - controlled reactions which is use hydrogen and ATP which carbon dioxide to produce sugar

Stage 2 of photosynthesis is controlled by what?

By enzymes

What do plants do with the glucose made during photosynthesis?

Used immediately in respiration

Converted in to starch for storage

Cellulose for structure

What is cellulose for?

Build long chains of cellulose for

Structure

What are the 3 limiting factors of photosynthesis?

Temperature

Carbon dioxide concentration

Light intensity

How much energy is passed on to an organism?

Only 10%

How much of the energy if lost?

90%

How is the energy is lost?

Heat

Movement

Indigested waste

how are nitrates dissolve?

In the soil water and adsorbed through the roots

What does nitrates produce?

Amino acids

What does nitrates synthesis into?

Into plant protein

What happen there is to much fertiliser?

it can leach into fresh water adding excess nitrates

What happens when algal populations increases?

Can cause algal bloom

What can algal bloom reduce?

Light levels reaching the water killing aquatic plants

Dead plants and algae can provide what?

Plenty food for bacteria

The more bacteria the more of what is used up?

Oxygen

Leaching can results in what?

Biodiversity decreasing

Why do farmers spray pesticides on to crops?

To increase crop yield by protecting the crops by killing pests

What is a mutation?

It’s a random change to genetic material (DNA)

What are the source of new alleles?

Mutations

What are the 3 types of mutations?

Advantageous

Disadvantageous

Neutral

What environmental factors can increase the rate of mutations?

UV rays

X-rays

What is the definition of adaptation?

Is an inherited characteristic that makes an organism well suited to survival in its environment

What does new alleles produced by?

Mutation can result in plants and animals becoming better adapted to their environment

Variation within a population can be a result in what?

To make it possible for a population to evolve overtime

What is natural selection?

The best adapted individuals in a population survive to reproduce passing on the favourable alleles the confer the selective advantage

Natural selection or survival of the fittest occurs when?

There are selection pressures

Initial population is separated by?

An isolation barrier

What is the definition of geographical?

Features such as rivers or mountains ranges isolate groups

What is ecological?

Isolated by such things as occupying different habitats

What is behavioural?

A population barriers caused by different in timing location that prevent members of the population from mating