1. A Plant’s Life
A Basic Understanding

2. What does a plant need to survive?
Light Energy
Water → H2O
Carbon Dioxide → CO2
Oxygen → O2
I could have told you that...

3. What are some ways a plant uses these resources?
Photosynthesis
Cellular Respiration
Transpiration

4. Photosynthesis Photosynthesis is the process
by which a plant uses light, water,
and carbon dioxide to create
energy in the form of
glucose -or sugar.
Photo-what?!

5. Photosynthesis
Ever wonder why plants are green? You can thank chlorophyll for that.
The cells of plant leaves contain
chloroplasts. These structures
contain chlorophyll, the pigment
responsible for converting light energy
into chemical energy.
Chlorophyll absorbs most wavelengths,
but reflects green wavelength back to
our eyes, this is why we see plants as
green!

6. Photosynthesis
The plant uses the light energy that is absorbed through the chlorophyll, and the carbon dioxide and water absorbed from its environment to undergo a chemical reaction and produce energy rich carbohydrates.
Carbon Dioxide + Water + Sunlight → Glucose + Oxygen
These carbohydrates are then stored and used for different life processes like making proteins or cellular respiration.

7. PHEW! Sounds like a lot of work.
Cellular Respiration
Before the plant can use the energy rich
carbohydrates created from
photosynthesis, a few things need
to happen…
Plants must break down glucose into a
usable form of energy called ATP
in order to perform necessary metabolic
processes, this is called respiration.
PHEW! Sounds like a lot of work.

8. Cellular Respiration
The first step of respiration is glycolysis. Glycolysis takes place in a cell’s cytoplasm. Here, glucose is broken down into pyruvate which releases energy in the form of ATP. If oxygen is available, the pyruvate then enters a mitochondrion.

9. Cellular Respiration
Upon entering the mitochondria, pyruvate goes through a variety of reactions and is broken down completely into carbon dioxide
and water.
The energy released in this reaction is stored
as ATP and this is what the plant uses for any
process that requires energy.
Chemical equation of the reaction:
Glucose + Oxygen → Carbon Dioxide + Water + Energy (ATP)

10. Transpiration Transpiration is the evaporation of
water from leaves through pores
known as stomata.These stomata
are responsible for gas exchange,
allowing carbon dioxide to enter as
water vapor leaves the plant.
Water is constantly being driven from a plants roots to its leaves through tubes called xylem. This constant flow of water is called a transpiration stream and is responsible for keeping the stem firm and capable of supporting the plant.
This stream also transports minerals from the soil throughout the plant and carries water to the leaves for photosynthesis.

11. Transpiration Many factors influence the rate of
transpiration in plants:
Wind- wind increases water loss
from the leaves surface, therefore
accelerating water loss from the plant .
Temperature- As temperatures
rise, the water holding capacity of the air increases and as temperatures decrease, the water holding capacity decreases. So, while an increase in temperatures raises transpiration rates colder temperatures will reduce them.

12. Transpiration Soil Water- soil provides the source
of water for transpiration to occur.
Transpiration rates increase if there is a
sufficient water supply in the soil because
the soil provides the water that courses
through the plant.
If the soil is dry, there will not be a
sufficient water supply to maintain the
water flow through the xylem. This
causes stomata to close and if loss of
firmness continues, the plant will wilt.

13. Transpiration Light- stomata are triggered to
open by light so carbon dioxide is
available for the light dependent
process of photosynthesis.