Option G - Blended Biology
Transcript Option G - Blended Biology
G 3.3 Discuss reasons for the conservation of biodiversity
using rainforests as an example.
• Rainforests are area in the world with highest
• Ethical- all plants/animals have a right to live.
Future humans have a right to see the world that
• Ecological- animals depend on other animals.
Species have already adapted
• Aesthetic- rainforests are beautiful
• Economic- Many resources lie in rainforests
G 3.4 List three examples of the introduction of alien
species that have had significant impacts on ecosystems.
• Purple loosestrife- overtook other native
plants and had no predators.
• Brown tree snake- extirpated bird species and
bats by preying on them.
• Ophiostoma ulmi- caused disease in trees that
killed many native trees
G 3.5 Discuss the impacts of alien species on ecosystems.
• Alien species can outcompete other native
species for limited resources like food and
• Can eat organisms and create a destroyed
food chain that must then adapt or become
• Can interbreed and cause extinction of a
species or create new species.
• Can keep other invader species under control.
G 3.6 Outline one example of biological control of invasive
• Control pest species
• Prickly pear cactus invaded Australia, but has
been controlled by South American moth
• Moth eats cactus
G 3.7 Define biomagnification
• Process in which chemical substances become
more concentrated at each trophic level.
G 3.8 Explain the cause and consequences of
biomagnification, using a named example.
• Animals at higher trophic levels need to eat
more organisms at lower levels in order to get
enough energy because 90% of the energy is
lost at each level.
• If a lower level species has poison in it, like the
mosquitos that were infected with DDT, the
larger animals, like geckos, that eat many of
them, are ingesting large amounts of poison
that could kill them.
G 3.9 Outline the effects of ultraviolet radiation on living
tissues and biological productivity.
• UV radiation causes DNA damage, like
mutations that cause protein malfunction. Or
• Can also damage organic molecules, hurting
enzymes, nitrogen-fixing bacteria in soil
• Causes eye damage (cataracts)
• Lower immune system
• Food shortage
G 3.10 Outline the effect of chlorofluorocarbons (CFCs) on
the ozone layer.
• CFCs speed depletion of ozone layer.
G. 3.11 State that ozone in the stratosphere absorbs UV
• There is a limit to UV absorption in the
atmosphere. Therefore the stratosphere
absorbs UV radiation.
G 4.5 Discuss the advantages of in situ conservation of
• Conserve natural habitat
• Ideal for threatened species
• Long term sustainability
G 4.6 Outline the use of ex situ conservation measures, including
captive breeding of animals, botanic gardens and seed banks.
• Replanting plants in areas they know will
survive, like botanic gardens.
• Captive breeding ensures that animals will
breed and increase population size.
• Seed banks allow seeds to spread easily in
order to fertilize.
G 5.4 Describe the methods used to estimate the size of
commercial fish in stocks.
• Tag and release
• Perception made by fisherman
• Record number and type of fish and throw
• Study catches made
G 5.5 Outline the concept of maximum sustainable yield in
the conservation of fish stocks.
• The fish population increases as fishermen
fish for the fish.
• Only until a point. Then the fish population
starts to decrease as they are over fished.
– Fish populations are very difficult to find and
therefore, people often disagree when it comes to
fishing in order to conserve fish.