Zusammenfassung der Ressource
PHOTOSYNTHESIS
- GLUCOSE is converted into
OTHER SUBSTANCES
- GLUCOSE is
transported around
the plant as
SOLUBLE SUGER
- Soluble sugars can DISSOLVE IN
WATER, which makes it easy to
TRANSPORT them to other
places in the plants
- Here's how plants USE the
glucose the make:
- For
RESPIRATION
- Plants use some
of the GLUCOSE
for RESPIRATION
- This releases ENERGY
so the rest of the
glucose can be
CONVERTED into useful
substances
- Making CELL
WALLS
- GLUCOSE is converted
into CELLULOSE for
making CELL WALL
- Stored in
SEEDS
- GLUCOSE is
turned into
FATS and OILS
for STORING in
SEEDS
- Stored in STARCH
- Some GLUCOSE is
turned into
STARCH and
STORED
- Starch is
INSOLUBLE-it DOESN'T
DISSOLVE IN WATER
- Starch is CONVERTED back into glucose
when supplies of the sugar are low
- Making PROTEINS
- GLUCOSE is combined
with other things to
make PROTEINS
- Proteins are used for
GROWTH and REPAIR
- There have been DIFFEENT IDEAS
about HOW PLANTS GAIN MASS
- When plants grow,
they GET HEAVIER
-they GAIN MASS
- ANCIENT GREEK
SCIENTIST thought that
plants gaind mass
from SOIL MINERALS
- But a scentist called van Helmont later
discovered that plants also gain mass from
OTHER SOURCES
- He dried some
SOIL, weighted it,
and put it in a pot
- He weighted a
SMALL WILLOW
TREE and planted
it in the soil
- He added
RAINWATER to the
pot whenever it
was dry
- 5 YEARS LATER,
the TREE had
grown and was
much HEAVIER
than at the start
- The mass of the SIOL had
HARDLY CHANGED at all
- Because the soil still
weighted the same,
van Helmont thought
that the TREE must
have GAINED MASS
from something other
then SIOL MINERALS
- The ONLY thing he'd added top the
pot was RAINWATER-so he concluded
the tree must have gained mass by
taking in WATER
- PRIESTLY'S EXPERIMENT showed
that PLANTS PRODUCE OXYGEN
- Many years after van
Helmont, a scientist called
PRIESTLY did this
experiment
- He placed a
BURNING
CANDLE in a
SEALED
CONTAINER
- The FLAME
WENT OUT and
COULDN'T be
RE-LIT
- He then placed a LIVING
PLANT in the container
- After a FEW WEEKS the
candle COULD BE RE-LIT
- He also did this experiment
- He also put a MOUSE in a
sealed container full of
BREATHED-OUT AIR. The
mouse DIED after FEW
SECONDS
- He filled another
container with
BREATHED-OUT AIR
- He put a LIVING
PLANT in the
container and waited
for a FEY DAYS
- He then put a MOUSE
in the container- this it
survived for A FEW
MINUTES
- He thought that the
CANDLE FLAME WENT
OUT and that the MOUSE
DIED because BURNING
and BREATHING had
TAKEN SOMETHING OUT
OF THE AIR
- From these experiments,
Priestly decided that PLANTS
somehow RETURN THIS
SUBSTANCE TO THE AIR
- Today we know that this substance is
OXYGEN- a product of photosythesis