Transcript b4e-h-pig-h - Macmillan Academy

B4 e-h Pig
• What’s wrong with
this food chain?
• Arrows pointing wrong way
• List 3 ways energy is
lost as you move up a
food chain
• Some parts don’t get eaten
• Some lost as faeces
• Some used in respiration (movement,
keeping warm etc)
• What is the
efficiency of
energy transfer in
the diagram?
• 16.5%
• Why can farmers
make more money by
keeping battery hens
in cages than they
can from free range?
• Less energy is lost in
moving and keeping
warm so farmers can
feed them less
• Name 2 biofuels
• Biogas (methane)
• Bioethanol
• Wood
• How do you make
biogas?
• Fermentation
• By bacteria
• In a digester
• Biomass fuels are
considered by some
to be environmentally
friendly. Suggest why
this might not be the
case.
• Natural habitats
destroyed to grow
biomass
• Biomass grown on
land normally used for
food
• Why do farmers use
pesticides?
• Less of the crop’s energy is lost to pests is a
better answer
• What are the
advantages of
biological control?
• No toxic chemical
• Useful insects not
harmed
• Top predators not
poisoned
• Why does crop
rotation reduce the
need for fertilizers?
• Nitrogen-fixing crops
can be grown once
every 4 years
• These contain Nfixing bacteria that
change nitrogen gas
into nitrates
• What 3 conditions do
decomposers need to
grow?
• Oxygen
• Water
• Warmth
• Why does
adding sugar or
salt preserve
food?
• Removes water using osmosis
• Name 2 uses of
decomposing
microbes?
• Making compost
• Breaking down
sewage
• How does carbon get into plants?
• Photosynthesis
• List 3 ways carbon is put back into the
atmosphere?
• Respiration by
animals
• Respiration by plants
• Respiration by
decomposers
(decomposition)
• Combustion
• Why is there more
carbon dioxide in the
atmosphere in the
winter?
• Less photosynthesis (fewer leaves)
• More combustion (heating)
• Name 2 bacteria that
add nitrates to the
soil?
• Nitrifying bacteria
• Nitrogen-fixing
bacteria