Biology Chapter 8 Photosynthesis Flashcards
Write the overall equation for the process of photosynthesis.
6 carbon dioxide (CO2) +6 water (H2O)—->Sunlight (energy) Glucose (C6H12O6)+6Oxygen (O2).
What kind of light drives photosynthesis?
Sunlight drives photosynthesis.
Describe the structure of a chloroplast and the functions of the structural components (stroma, grana, thylakoid compartment, thylakoid membrane).
For ex. if you have a leaf inside that leaf there are mesophyll cells, inside one of the mesophyll cells is the chloroplast, inside of the chloroplast is the stoma the pancake stack shaped things, one on the pancake shaped stacks is called a grana. Inside of the grana, one of the pancake looking peaces is called a thylakoid, the inside of the thylakoid is called the thylakoid compartment and around it is a thylakoid membrane.
The stoma is open during the day to let carbon dioxide pass into leaves and water vapor pass out of them.
Chloroplasts can be defined as the organelles within plants and algae cells that are the sites of photosynthesis.
Inside the interior of the chloroplast there is a network of chloroplast membranes, active in photosynthesis, called thylakoids.
The thylakoids stack on top of each other called grana. Thylakoid are immersed int he liquid material of the chloroplast, the stoma.
In the thylakoid and the stoma is where all the steps of photosynthesis occurs.
What is chlorophyll a?
Chlorophyll a is the main pigments of photosynthesis because it is the most absorbent.
What is the purpose of pigments other than chlorophyll a in photosynthesis? What are these pigments called?
Pigments are any molecule that can observe visible light. **
Briefly describe the main purpose of each of the two stages of photosynthesis.
The first stage (the photo of photosynthesis), the power of sunlight will do two things, strip water of electrons and then boost electrons to a higher level. When the excited electron gets passes to a mobile electron carrier, called NADP+, which transfers them to a second set of reactions. In the second stage (the synthesis part of photosynthesis), the electrons come together with carbon dioxide and sugar. The attachment of the electrons and CO2 to this second sugar produces a high-energy sugar meaning food.
What is a photosystem?
Photosystems are multiple units that bring together electrons derived from water an energy derived from the sun.
What are the components of a photosystem?
A group of a few hundred pigment molecules that serve to absorb the sunlight. At the center of the antennae system, however, there is a reaction center- a pair of special compounds that first receive the solar energy from photosystem pigments and then transfer the solar energy into chemical energy.
How do photosystems function in electron flow?
The solar energy gathered by photosystems II and I are used to energize electrons that exist within the photosystems’ reaction center. Energetically, the electron is boosted up, and then move down, two energy hills. Physically, they first move to primary electron acceptors and then down electron transport chains until they are at last taken up by NADP+ to form NADPH. The NADPH molecules then transfer the electrons to the Calvin cycle, in which they are used to make sugars. **
Describe the light reactions of photosynthesis.
The first step of light reaction us that the solar energy, collected by photosystem II’s antennae molecules, arrives at the reaction center. This energy then gives a boost to an electron in the reaction center. The electron physically moves to another part of the reaction center complex, the primary electron acceptor, and is also pumped up the energy hill. With this activity, the reaction canter chlorophyll had lost an electron. That loss leaves an energy “hole” in the chlorophyll, making it an oxidized agent. With the energy provided be this imbalance, a special enzyme in the reaction center splits water molecules the lie within the thylakoid compartment. These water molecules are now being oxidized, which means they are losing electrons. The electrons travel to the reaction center, where they will be the next electron in line for an energy boost. **
Where in the chloroplast do these reactions occur?
Within he thylakoid membrane.
What is the purpose of H2O molecules in the light reactions?
The splitting of water happens, Hydrogen atoms are removed atoms are removed from H2O, while the oxygen is left behind. When two liberated oxygen atoms come together in the thylakoid compartment, the result is O2- the form of oxygen that exists in our atmosphere.
What are the products of the reactions?
O2, being released into the atmosphere, maybe sugar?
How does O2 get out of the chloroplast and leaf into the atmosphere?
o
Briefly describe where and how ATP is produced in Photosystem I.
o
