Biology
Plant Transport Systems
& Photosynthesis
Photosynthesis Learning Intentions
1.
2.
3.
4.
What is Photosynthesis?
Leaf structure and function
What are the plant transport systems?
How many stages are there in
photosynthesis?
5. What happens in each stage of
photosynthesis?
6. How can photosynthesis be measured?
7. What are the factors that can limit
photosynthesis?
1. What is Photosynthesis?
Photosynthesis is a series of enzyme controlled
reactions which allow green plants to make their
own food
Photosynthesis changes light energy from the
sun into chemical energy in the form of ATP
The word equation for photosynthesis is:LightEnergy
Photosynthesis video
Stand and Deliver
2.1 Leaf Structure
Waxy Cuticle
Upper Epidermis
Vein
(Xylem & Phloem)
Palisade Mesophyll
Spongy Mesophyy
Air space
Stoma
Guard Cells
2.2 Leaf Structure and Function
Leaf Part
Function
Waxy Cuticle
Waterproof outer layer
Epidermis
Protective outer layer
Xylem
Transports Water
Phloem
Transports Glucose (Sugar)
Palisade Mesophyll
Contain lots of chloroplasts for
photosynthesis
Spongy Mesophyll
Loosely arranged for gas exchange
Moist air space
Moist to allow gases to dissolve
Stoma
Allows Carbon Dioxide in and
Oxygen out of leaf
Guard Cells
Open and close stomata
3.1 Plant Transport Systems (WATER)
Transport of Water
Transpiration is when water
moves from the roots up to
the leaves of a plant
Water is needed by the plant
for photosynthesis
Water moves from a region
of high water concentration
(in the soil) to a region of
lower water concentration (in
the root hairs) by osmosis
Water travels up the stem
of a plant in non-living xylem
vessels to the leaves
Xylem Vessels are hollow and
are made of rings of lignin
Practical: Tomato Sauce and
Celery
3.2 Plant Transport Systems (GLUCOSE)
Transport of Glucose (Sugar)
Glucose is made in the leaves by
Photosynthesis
Glucose can travel from the
Leaves to all other parts of the
plant in Phloem.
Phloem vessels are living cells
made of sieve tubes and
companion cells
3.3 Plant Transport Systems
Root Diagram of
Xylem and Phloem
Stem Diagram
of Xylem and Phloem
Plant Transport Video Clip (2:59)
3.4 Plant Transport Systems (Gas Exchange)
(Turgid)
Practical: See Stomata
(Flaccid)
Photosynthesis Animation
3.5 Gas exchange in leaf
Cuticle
Upper
Epidermis
Palisade
Xylem
Mesophyll
Vascular
Phloem
Spongy
Mesophyll
Lower
Epidermis
Carbon Dioxide gas enters
Stoma
Guard Cells
Oxygen gas leaves the leaf
Bundle
4. Stages of Photosynthesis
grana
Photosynthesis occurs in a
chloroplast of a leaf
Stage 1 – Photolysis
Occurs in the grana
of a Chloroplast
Stage 2 – Carbon Fixation
Occurs in the stroma
of a Chloroplast
stroma
A Chloroplast
5.1 Stage 1 - Photolysis
PHOTOLYSIS
Photolysis is the first stage of Photosynthesis
Light Energy from the sun is trapped by
chlorophyll in chloroplasts.
The Light Energy is used to split water into
Hydrogen and Oxygen.
Light
Energy
The Light Energy is converted into Chemical
Energy in the form of ATP
The 3 products of photolysis are Oxygen, ATP
and Hydrogen
Water
Oxygen is released to the air (as a by-product)
ATP and Hydrogen are passed onto the second
stage of Photosynthesis (Carbon Fixation)
Hydrogen
Oxygen
ADP + Pi → ATP
5.2 Stage 2 – Carbon Fixation
Stage 2 - Carbon fixation
ATP and Hydrogen (from
Photolysis) are used with
carbon dioxide to make
the product glucose
ATP
Glucose can be:1.
Converted to an energy source
(in respiration)
2.
Stored as Starch
3.
Made into Cellulose (for cell
walls)
Hydrogen
Carbon
Dioxide
Carbon Fixation
Glucose
Practical: Testing leaves for starch
5.3 Summary Stage 1 & Stage 2
Photosynthesis Stage
1st Stage
2nd Stage
Name
Photolysis
Carbon Fixation
Where in chloroplast?
Grana
Stroma
Requires Light
Yes
No
Requires Chlorophyll
Yes
No
Raw Materials
Water
Carbon Dioxide
(from soil via roots) (from air via stomata)
Products
Hydrogen
Oxygen
ATP
Glucose
6. Measuring Photosynthesis
Count number of oxygen bubbles
Upside down test tube
Water
Upside down funnel
Cabomba
7. Limiting Factors
The factors that limit the rate of photosynthesis are:
Light Intensity
Light Energy is an essential factor needed for to split
Water into Hydrogen + Oxygen
Carbon Dioxide Concentration
Carbon Dioxide is a raw material needed to help make
Glucose
Temperature
Photosynthesis is controlled by enzymes. Enzymes
work too slowly at low temperatures, and become
denatured at too high temperatures
*If the rate of photosynthesis decreases, the
rate of cell growth decreases
8. Photosynthesis & Industry
Photosynthesis
Carbon Dioxide + Water
light energy
Oxygen + Glucose
chlorophyll
Limiting Factors
Temperature
Light Intensity
Carbon Dioxide Concentration
Control of Limiting Factors
Heaters
Supplementary Lighting
Heaters which burn paraffin to increase carbon dioxide
M&S Letter
Photosynthesis Activities
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Water Transport Practical – Celery/Flowers/Tomato Sauce
Stoma Pore Practical – Nail Varnish/Germaline New Skin
Rate of Photosynthesis Practical
Limiting Factors and Photosynthesis Practical - Design
Matching Cards (See N4/5 Drawer)
True and False Statements – Revision
Compare and Contrast Photosynthesis and Respiration
Photosynthesis song
Textbook Questions
Homework
Past Paper Questions
Quick Quiz