Section 3.3 - Photosynthesis Photosynthesis uses __________________________________ from the sun to fix

________________________ into _______________________________ (namely glucose).

The captured radiant energy is stored within the _______________ of the carbohydrate as chemical energy

Photosynthesis is used by many autotrophs to make their own foodo egs. vascular plants, algae, cyanobacteria

Write the net equation for photosynthesis below in words and in chemical formulas (pg. 83 of your text)

Photosynthesis and Cellular Respiration appear to be ___________________________________ , but they use very different ______________________________.

The processes are similar in that both use:1. _______________________________________________

2. _______________________________________________

3. _______________________________________________

Plants are made of various types of tissueso egs. Stem, leaves, roots, reproductive organs

The main site of photosynthesis is the ____________, although chloroplasts are found in all green plant parts

Stamata (singular =stomate) are pores on the underside of leaves which allow for gas exchange. To conserve water, these can be opened and closed

Opening the Stomata Closing the Stomata

Chloroplast Pore

Guard Cells

The Structure of the Chloroplasts

Zoomed in on Granna:

Stages of PhotosynthesisPhotosynthesis is divided into two stages:

1. Light dependent reactions (light reactions) 2. Light independent reactions (dark reactions)Uses sun’s energy to produce: Uses stored chemical energy to produce

Don’t be fooled!!!

The Electromagnetic Spectrum

The full range of wavelengths of light emitted from the sun is known as the electromagnetic spectrumVisible light is between ______________________.Light has properties of both waves and particles

Light travels in bundles of energy called ___________.The energy from photons is used to initiate photosynthesis.

Photosynthetic pigments absorb light Each pigment can absorb light (photons) within a specific range of _________________________ Wavelengths that are not absorbed are said to be ____________________ or reflected

◦ This is the light we see determines what colour we see The most common pigments in plants are ________________________ and _________________________

◦ What colours are absorbed? ______________________ (optimal @ 400-450nm) What colours are reflected? ______________________ (optimal @650-700nm) _________________________________

PhotosystemsWhere do the light dependent reactions take place? ____________________________________________________________________________________________ Groups of molecules responsible for the light dependent reactions are called photosystems

Each photosystem has:1. _______________________________________

• 200-400 _________________________ molecules, accessory pigments (ex. carotenoids)

2. _______________________________________

• a specialized _______________________ molecule with associated proteins

3. _______________________________________

There are 2 photosystems in plants: o Photosystem I (PS I) & Photosystem II (PS II)o Other names (used by text)

PS I absorbs best at ________________; called _______________ PS II absorbs best at ________________; called _______________

How Photosystems Capture Light Energy:

1. ______________ of light are absorbed by antenna pigments causing them to move from _________________________ to an __________________________.

2. “Excitation” energy is passed along chlorophyll molecules until it reaches the __________________________.

3. _______________________________ in the reaction centre absorbs the energy.

4. The high-energy state of chlorophyll a causes it to ______________________________.

5. The __________________________________________________ takes the electrons from chlorophyll a

this process is called ___________________________________.

HoweworkRead Section 3.3 up to “The Calvin Cycle”

1) Do section review 1-4 on pg. 942) Explain the difference between the cyclic and non-cyclic pathway