Chapter Eight Concept 8.1

- I haven't been blogging in quite a while now, so I apologize if my format is a little messed up, or if my blogs are illegible.   :) - 

Photosynthesis uses light energy to make food. 

- a chloroplast is the cellular organelle where photosynthesis takes place. 

-Chlorophylls give chloroplasts the green color, or the plant's pigment.

-Chloroplasts are concentrated in the mesophyll; the inner layer of tissue in a leaf.

-On the surface of the leaf there are small pores called stomata.

-Through the stomata, carbon dioxide enters and leaves.

-Veins of the leaf carry water, and nutrients from the roots to the leaves, and deliver organic molecules facilitated in leaves to other parts of the plant.

-Chloroplasts have an inner and outer membrane.

-Just as how a mitochondrion's inner membrane encloses a thick fluid called matrix, the chloroplast encloses a thick fluid as well, but it is called stroma.

-The stroma covers disk like sacs called thylakoids, and thylakoids have membranes surrounding the interior space.

-Thylakoids are arranged in stacks, also called grana.

-The structure of the chloroplast organize the numerous/complex series of chemical reactions that make up overall processes of photosynthesis. 

-Photosynthesis takes place in the thylakoid membrane, or in the stroma.

-The opposite reaction of Cellular Respiration occurs during photosynthesis.

  

cellular respiration                       photosynthesis

-Instead of electrons of water falling, the are boosted "uphill" by sunlight's energy.

-The boosted electrons are used with carbon dioxide and hydrogen ions to produce sugar molecules. 

- Instead of having three complicated steps that cellular respiration has, two main stages; light reactions, and the Calvin cycle. 

- The process of light reactions convert energy in sunlight to chemical energy.

Light Reactions:

1) Chlorophyll molecules in membranes capture light energy.

2) Chloroplasts use the captured energy to remove electrons from water.

3) The process splits water into oxygen and hydrogen ions, and oxygen becomes a waste product, and the stomata allows oxygen to seep through the stomata into the atmosphere. 

4) Water's electrons and hydrogen ions make an energy rich molecule called NADPH, made by chloroplasts.

5) Chloroplasts also capture light to generate ATP. 

Results; One NADPH molecule, and one ATP molecule. 

-The calvin cycle makes sugar from the atoms in carbon dioxide plus the hydrogen ions and high-energy electrons carried by NADPH. 

-enzymes for the Calvin Cycle is located outside the thylakoids and dissolved in the stroma. 

-ATP produced by the light reaction provides energy to create sugar. 

-Calvin cycle requires two inputs; NADPH and ATP.

Concept Check 8.1:

1. Draw and label a simple diagram of a chloroplast that includes the following structure: outer and inner membranes, stroma, thylakoids.  

2. What are the reactants of photosynthesis? What are the products? 

As you can see in the equation of photosynthesis which is :

6CO2+6H2O->->->C6h1206+6O2

The reactants are carbon dioxide and water, and the products are sugar and oxygen.

3. Name the two main stages of photosynthesis. How are the two stages related?

The two main stages of photosynthesis is light reactions and the Calvin cycle. The light reaction cycle creates a NADPH molecule made from water's electrons and hydrogen molecules, and an ATP molecule from captured light energy, and the Calvin cycle creates sugar using the atoms in carbon dioxide and hydrogen ions and high-energy electrons from NADPH. The energy from ATP proves the energy to make sugar.  

Key Terms 8.1-

Chloroplast: Organelle found in some plant cells and certain unicellular organisms where photosynthesis occurs. 

Chlorophyll: Pigment that gives a chloroplast its green color; uses light energy to split water molecules during photosynthesis.

Stroma: Thick fluid contained in the inner member of a chloroplast.

Thylakoid: Disk-Shaped sac in the stroma of a chloroplast; site of the light reactions of photosynthesis. 

Light Reactions: Chemical reactions that convernt the sun's energy to chemical energy; takes place in the membranes of thylakoids in the chloroplasts.

Calvin cycle: Cycle in plants that make sugar from carbon dioxide, H+ions, and high-energy elections carried by NADPH.