Transcript Plants and Photosynthesis

Plants and
Photosynthesis
Plants
 Plants are made up
of different parts.
 There are many
different kinds of
plants:
 Angiosperms have
flowers.
 Mosses and liverworts
don’t have a classic
plant structure.
 Cacti don’t have
Photo courtesy of
leaves.
http://plants.ifas.ufl.edu/images/schter/sciter4.jpg
Plants cont’d
 Basic similarity is that plants produce
their own energy.
 Vascular plants are a very common plant
type. They have the following structures:
 Roots
 Stems/shoots
 Leaves
Plants cont’d
 Have a go at drawing this plant in your
book. Make sure you label it too. Make
sure you label the 3 basic parts.
Image courtesy of
http://www.phschool.com/science/biology
_place/biocoach/plants/basic.html
Plant parts
Write down these notes in your books.
 Roots: are for soaking up water and minerals
from the ground. They also anchor the plant.
 Stems/shoots: are support structures that
transport food and water.
 Xylem: tubes that transport water and minerals upwards.
 Phloem: tubes that transport sugars downwards.
 Leaves: are the part that does
photosynthesis/makes energy.
Plants
 I will give you a copy of the plant picture
to glue into your books.
 Glue it in next to or near the picture that
you drew of the plant.
Leaves and
photosynthesis
 We are now going to
learn about leaves and
photosynthesis.
 Leaves make energy via
photosynthesis.
 What do plants do? They
grow.
 What do we as humans
need to make us grow?
Food/energy.
Photo courtesy of http://plants.ifas.ufl.edu/images/aespav/aespav3.jpg
Leaves and
photosynthesis
 Now the question is how do
plants grow?
 They need energy too. But
plants can produce their energy.
 Plants use light to convert water
and carbon dioxide into
energy/plant material/growth.
 This process is called
photosynthesis.
Photosynthesis
 Carbon dioxide + water + light
 glucose and oxygen

6CO2
+ 6H2O + light and chlorophyll
 C6H12O6 + 6O2
 What is glucose? It’s a type of sugar.
Somewhere in the leaf this process is
happening. The part of the leaf that is
responsible for this is the chloroplast (the part
we see as green in the leaf).
Photosynthesis
 Photosynthesis takes place in the chloroplast
of a cell because of a pigment called
chlorophyll which traps the light.
 Like I mentioned earlier the xylem transports
the water to the leaf.
 But where does the plant get the CO2 from?
From the air, through a pore in the underside of
a leaf called a stomata. Also the oxygen is
released through this same pore/stomata.
Photosynthesis
 A plant gets CO2 from the air through a pore known as
a stomata. Plants release oxygen through stomata.
 Now photosynthesis is more complex than the equation
looks, because there are also enzymes involved to
make the reaction occur.
 Basically there is one part of the reaction that requires
light energy to transform into chemical energy (ATP),
and that is called the light reaction, and then there is a
second part where enzyme reactions cause carbon
dioxide and hydrogen ions to combine to form glucose,
and this part is the dark reaction.
Photosynthesis
 Light reaction: light energy  chemical
energy  ATP and NADPH
 Dark reaction: carbon dioxide and energy
 glucose
 This is also known as the Calvin Cycle.
Photosynthesis
Videos
 We are now going to look at a couple of
videos about photosynthesis.
 So go back to your wiki page and follow
the link to the videos.
References
Content
 Phillips, G et al, 2004, Sci3, Pearson
Education Australia, Sydney.
 www.biology4kids.com/