1-10 1. What color does chlorophyll reflect? 2. What organisms can make their own energy (there are at least 4 correct answers)? Question of the Day.

1-101-10

1. What color does chlorophyll reflect?

2. What organisms can make their own energy (there are at least 4 correct answers)?

Question of the DayQuestion of the Day

1-101-10Photosynthesis uses…

Photosynthesis produces…

ReviewReview

Organisms that make their own energy = ???

Organisms that have to eat to get their energy = ???

3 cellular activities that require energy = …

1-101-10Photosynthetic pigments …

What colors does a plant primarily use for photosynthesis?

How do you know?

ReviewReview

1-111-11

1. How are heterotrophs and autotrophs different?

Question of the DayQuestion of the Day

Why is the sky blue?Why is the sky blue?http://science.howstuffworks.com/nature/climate-weather/atmospheric/sky.htm

http://spaceplace.nasa.gov/en/kids/misrsky/misr_sky.shtml

PhotosynthesisPhotosynthesis Light is Light is absorbedabsorbed – – excites excites

electrons in pigments electrons in pigments = start of = start of photosynthesisphotosynthesis

Explain why a leaf appears greenExplain why a leaf appears greenBecause it is absorbing most of Because it is absorbing most of

the other wavelengths of light the other wavelengths of light and reflecting greenand reflecting green

Lets Photosynthesize! Lets Photosynthesize!

It all starts with a….It all starts with a….

Lets Photosynthesize! Lets Photosynthesize!

Calvin cycle

1st stage

2nd stage

Lets Photosynthesize! Lets Photosynthesize!

LETS PHOTOSYNTHESIZE! LETS PHOTOSYNTHESIZE!

Light reactions = first stage of photosynthesis – light energy is converted to chemical energy (energy from the sun ATP + NADPH)

The LeafThe Leaf What organelle in the leafWhat organelle in the leaf

is responsible for photosynthesis?is responsible for photosynthesis? ChloroplastChloroplast

Parts of a chloroplastParts of a chloroplast Thylakoids - Flattened sacs where photosynthesis Thylakoids - Flattened sacs where photosynthesis

occurs – surrounded by a membraneoccurs – surrounded by a membrane Grana – Grana –

Stacks of thylakoidsStacks of thylakoids Stroma –Stroma –

Solution that Solution that surrounds the granasurrounds the grana

The Light-Dependent Reactions: The Light-Dependent Reactions: Generating ATP and NADPHGenerating ATP and NADPH

The light-dependent reactions The light-dependent reactions encompass the steps of encompass the steps of photosynthesis that directly involve photosynthesis that directly involve sunlight.sunlight.

The light-dependent reactions The light-dependent reactions occur in the thylakoids of occur in the thylakoids of chloroplasts. chloroplasts.

Thylakoids contain clusters of Thylakoids contain clusters of chlorophyll chlorophyll and proteinsand proteins known as known as photosystemsphotosystems..

Photosystems Photosystems absorb sunlight and absorb sunlight and generate high-energy electronsgenerate high-energy electrons that are that are then passed to a series of electron carriers then passed to a series of electron carriers embedded in the thylakoid membrane.embedded in the thylakoid membrane.

The Light-Dependent Reactions: The Light-Dependent Reactions: Generating ATP and NADPHGenerating ATP and NADPH

ChloroplastChloroplast

Light ReactionsLight Reactions1.1. Occurs on thylakoid membrane Occurs on thylakoid membrane 2.2. Chlorophyll absorbs light and electrons get excited – flow Chlorophyll absorbs light and electrons get excited – flow

on electron transport chainon electron transport chain3.3. Energy in excited electrons is used to create NADPH and Energy in excited electrons is used to create NADPH and

ATPATP These are temporary energy carrier moleculesThese are temporary energy carrier molecules

4.4. Water – electron donor – releases Water – electron donor – releases O O22

5.5. ATP + NADPH are then used to ATP + NADPH are then used to create glucose in the Calvin Cycle create glucose in the Calvin Cycle

Chlorophyll absorbs light and electrons are excited. Chlorophyll absorbs light and electrons are excited. These electrons flow on electron transport chain along These electrons flow on electron transport chain along the thylakoid membrane. As the electron is transported the thylakoid membrane. As the electron is transported it loses some energy and is used create a H+ it loses some energy and is used create a H+ concentration gradient inside the thylakoid, which is concentration gradient inside the thylakoid, which is later used to create ATP from ADP +P. The electron later used to create ATP from ADP +P. The electron finally reaches the final electron acceptor and is finally reaches the final electron acceptor and is combined with NADP+ and a H+ to form NADPH, which combined with NADP+ and a H+ to form NADPH, which is an energy carrier molecule. Water is split to (2 His an energy carrier molecule. Water is split to (2 H22O O

= 4H= 4H++ + 4e + 4e-- + O + O22) to replace the lost electrons. ) to replace the lost electrons.

One of the most important steps (water molecules split):2 H2O = 4H+ + 4e- + O2

Light ReactionsLight Reactions

protons

electrons

oxygen

1. During the light reactions ___ and ___ are used to make ___, ___, and ___.

REVIEWREVIEW

DRAW!DRAW!Also label: thylakoid grana stroma

1-131-13

1. During the light reactions ___ and ___ are used to make ___, ___, and ___.

Question of the DayQuestion of the Day

One of the most important steps (water molecules split):2 H2O = 4H+ + 4e- + O2

Light ReactionsLight Reactions

protons

electrons

oxygen

http://www.youtube.com/watch?v=HrMka8vj73U http://www.youtube.com/watch?v=v590JJV96lc

http://www.youtube.com/watch?v=TwnJtsL0tfw

Light ReactionsLight Reactions

1-131-13

Quiz up to and including the light reactions (notes pages 1-7) on

Wednesday 1-19

AnnouncementAnnouncement

1-131-131. How are heterotrophs and

autotrophs different?

REVIEWREVIEW

2. Photosynthetic pigments …

3. What colors does a plant primarily use for photosynthesis?

How do you know?

1-131-134. Photosynthesis uses…

Photosynthesis produces…

ReviewReview

5. Where do the light reactions take place?

6. Why is the splitting of water molecules important for photosynthesis?

1-131-13ReviewReview

7. The light rxns use…

To produce…

8. What’s the electron transport chain?

QUICK TALKQUICK TALKLight Reactions

Glucose

Chloroplast

Autotroph

Chlorophyll

Chemosynthetic bacteria

Thylakoid

Carbon dioxide

Photosynthesis

Producer

Stroma

Heterotroph

NADPH