Biological
catalysts
that speed
up chemical
reactions
Work best at
optimum pH or
temperature
Exceeding optimums
makes the enzyme
change shape, or
denature
Lock and Key Model
Respiration
Aerobic
Energy used for
movement, active
transport and
synthesis of large
molecules
With
oxygen
Releases
more energy
per glucose
molecule
Equations
A series of food
chemical reactions
that release energy
by breaking down
large food molecules
Anaerobic
Without oxygen
Less energy per glucose molecule
Equations
Animal cells and some bacteria
Glucose ==> Lactic Acid
Plant cells and some microorganisms
Glucose ==> Ethanol + Carbon Dioxide
Fermentation
When microorganisms break down sugars into
other products as they respire anaerobically
Biogas
Fuel for heating and lighting
Lots of different
microorganisms used to
produce it
Ferment plant and animal
waste, which contains
carbohydrates
Biogas produced mainly
made of methane and
carbon dioxide
Bread
Made using yeast
Yeast ferment carbohydrates in flour and
release carbon dioxide, causing bread to rise
Alcohol
Yeast ferment sugar
to form alcohol
Sugar used in
alcohol production
comes from grapes
(for wine) and barley
(for beer)
Photosynthesis
A series of food chemical reactions that uses
energy from sunlight to produce food
Produces glucose - a sugar
Happens in leaf cells
Chlorophyll is a green substance which absorbs
sunlight and allows energy to be used to convert
carbon dioxide and water into glucose
Equations
Glucose
Used for respiration - releases energy from glucose
Used to make chemicals for growth
Converted into cellulose for cell walls
Combined with nitrogen to make amino acids to make proteins
Helps to make chlorophyll
Stored as starch - in roots, stems and leaves, used
when rates of photosynthesis is slower, like winter
Factors
When a factor stops
photosynthesis from
happening any faster, it
becomes a limiting factor
Light
Carbon Dioxide
Temperature
Diffusion - passive overall movement
of particles from a region of higher
concentration to a region of lower
concentration
Osmosis - overall movement of water
from a region of higher concentration to a
region of lower concentration through a
partially permeable memberane
Active Transport - overall movement of chemicals across a cell
membrane from a region o lower concentration to a region of higher
concentration using energy released by respiration