Enzyme Activity in Photosynthesis | Education - Seattle PI

Whats the point? So what, we can make mathmatical models of enzyme reactions driving photosynthesis. Why do you think we should care about all of this? (If you are having trouble I suggest you take a deep breath!)

What enzyme catalyses the reaction immediately following the one catalyzed by Rubisco?

-> 2 NADH created that carry e- to ETC Oxidative Phosphorylation ATP
Synthase Krebs Cycle:
Remainder of Carbon from original Glucose is converted to CO2 (exhaled)
Many electron carriers produced (NADH, FADH2 -> go to ETC
A little bit of ATP produced Electron Transport and Chemiosmosis
Start with electron carriers from previous steps (NADH, FADH2)
They "drop off" the electrons
H+ ions are pumped across membrane, create gradient
H+ then flow back in through ATP synthase and create ATP (oxidative phosphorylation) Occurs in Cytoplasm Occurs in Mitochondria Energy Production and Metabolism Free Energy Free Energy G: Energy of Products - Energy of Reactants Glucose has high free energy CO2 has lower free energy Exergonic
This change (high to low) gives a negative delta G
The energy released by breaking down glucose is used to make ATP directly, or captured by electron carriers and used to make ATP in ETC
Catabolic: breaking bonds Energy Released Glucose has high free energy CO2 has lower free energy Energy Required to take CO2 and make Sugars Endergonic
This change (low to high) gives a positive delta G
Energy is required
Anabolic Therefore...breaking down glucose gives overall negative delta G, energy is released that is transformed into the energy stored in ATP When Cells "Make" Energy, They Make ATP Triphosphate:
The phosphates are all negatively charged
"Like" charges want to repel each other
The 3 phosphates, when bound together, act like a loaded spring, or charged battery Energy is created in the mitochondria as ATP so that it can travel to other locations in the cell to be used Watch Video Watch Video Only Occurs if Oxygen Present

Oxygen is the last electron acceptor in ETC

If no oxygen is present, then there is fermentation No oxygen, so no electron transport Watch Video The Role of Enzymes in Metabolism Enzymes
Biocatalysts: Speed up a chemical reaction without being used in the process
Are made from proteins (some are RNA)
Work by lowering the activation energy!
Steps in metabolic pathways (like glycolysis, Krebs cycle, etc) are carried out by enzymes, and are regulated Polysaccharide
(Starch) Monosaccharide Blue Line
A polysaccharide can be broken down to monosaccharide by boiling in water with an acid
Boiling provides the large amount of energy to help break the bonds
This is not realistic inside our bodies!


Enzyme Activity in Photosynthesis | Sciencing

Learn how plants harness the sun's energy using photosynthesis, and the factors which affect this process.

In Photosynthesis, photons of light are absorbed by chlorophyll molecules, causing them to donate a high-energy electron that is put to work making NADPH and pumping protons to produce ATP. In this section of the lab you will examine recent evidence that proteins embedded in the thylakoid membranes within the chloroplasts of photosynthetic organisms are acting as an antenna to facilitate light capture.


Photosynthesis, Respiration and Enzyme Action

Photosynthesis occurs in two stages. These stages are called the light reactions and the dark reactions. The light reactions take place in the presence of light. The dark reactions do not require direct light, however dark reactions in most plants occur during the day.

Most Important Enzyme in the World, rubisco ..

And, once you master your knowledge of photosynthesis, you can relax in the sun with a greater appreciation for the O2 you breathe, knowing that it is produced from the photosynthetic process. Don’t forget the sunscreen—at least SPF 30—you aren’t a plant, after all. Finally, you will realize that the beachside smoothie you are sipping, along with everything else that you have ever eaten, or will ever eat, relies on photosynthesis either directly or indirectly as its source of energy. Unless, of course, you have gotten into the habit of snacking on chemoautotrophs that live in rocks or deep-sea hydrothermal vents. They don't use photosynthesis.

How can the answer be improved?

In this weeks lectures we explored the relationships between living things and energy transfer. In this lab we will more specifically consider the relationships between energy and mass transfer in photosynthetic carbon gain. For the next part of this lab we will utilize the ExPASy (Expert Protein Analysis System) proteomics server of the Swiss Institute of Bioinformatics (SIB). Go to the and search for "Ribulose-bisphosphate carboxylase". From the description answer the following questions: