Campbell Biology Chap 10 Flashcards
Where does photosynthesis occur in plants
Chloroplasts
Which cells are most chloroplasts contained within
mesophyll cells inside the leaf of the plant
What is the Photo part of Photosynthesis
Light reaction
What is the Synthesis part of Photosynthesis
Calvin Cycle
What do light reactions produce
capture energy from sunlight, which they change to chemical energy that is stored in molecules of NADPH and ATP. The light reactions also release oxygen gas as a waste product.
What do Calvin Cycle produce
uses the ATP and NADPH produced during the light reactions to fix carbon dioxide (CO2) and synthesize sugars. 1
What is Carbon Fixation
the process incorporating CO2 into existing organic molecules within the chloroplast and then reducing the fixed carbon to carbohydrates
Where do light reactions occur
Thylakoids
Where does Calvin Cycle occur
Stroma
When Light Interacts with matter, what happens
it can be reflected, transmitted, or absorbed
What are Pigments
substances that absorb visible light.
Which colors drive photosynthesis most efficiently
Violet-blue and Red light
What are the 3 different pigments found in a chloroplast
Chlorophyll A, Chlorophyll B, and Carotenoids
Role of the Pigment Carotenoid in chloroplast
broaden the absorption spectrum and, more importantly, provide photoprotection
What happens to a Pigment Molecule as photons get absorbed
Electron gets excited, producing heat
First step of Light reaction
transfer of an electron from the reaction-center chlorophyll a pair to the primary electron acceptor, which is powered by light
What is a photosystem
consists of a reaction-center complex surrounded by light-harvesting complexes. The reaction-center complex contains a special pair of chlorophyll a molecules and a primary electron acceptor.
What is linear electron flow
light reactions of photosynthesis use light energy to drive the synthesis of ATP and NADPH through a flow of electrons
What is the Purpose for light reactions
to convert solar energy into chemical energy in the form of ATP and NADPH. These molecules then provide the energy and reducing power needed for the Calvin cycle to synthesize carbohydrates
What process do Chloroplasts use to create ATP
Chemosis, same as mitochondria
How is Chemosis used by Chloroplasts to create ATP
protons are pumped from the stroma into the thylakoid space, also creating a proton gradient
Calvin Cycle doesnt directly produce glucose, what does it produce
glyceraldehyde 3-phosphate (G3P)
How many cycles needed for 1 G3P molecule to form from Calvin Cycle
3 times
What are the 3 steps in Calvin Cycle
Carbon fixation, reduction, and regeneration of CO2 acceptor
What happens in Carbon Fixation step of Calvin Cycle
each CO2 molecule is attached to a five-carbon sugar called ribulose bisphosphate (RuBP). The resulting six-carbon molecule is unstable and immediately breaks down into two molecules of 3-phosphoglycerate.
What happens in reduction phase of Calvin Cycle
each 3-phosphoglycerate molecule is phosphorylated by ATP, forming 1,3-bisphosphoglycerate
What happens in regeneration phase of Calvin Cycle
the carbon skeletons of the five remaining G3P molecules are rearranged into three molecules of RuBP, the initial CO2 acceptor. This process requires the expenditure of three more ATP molecules. Once RuBP is regenerated, the cycle can continue.
What molecules are used to net 1 G3P molecule in the calvin cycle
nine ATP and six NADPH molecules, which are replenished by the light reactions.
What is Photorespiration
O2 is added to the Calvin cycle, producing a two-carbon compound that is then processed in peroxisomes and mitochondria, releasing CO2. Photorespiration consumes ATP and produces no sugar, effectively reducing photosynthetic output and wasting energy.
