Chapter 10- Photosynthesis

Where does the oxygen in photosynthesis originate from?

The oxygen released during photosynthesis comes from the splitting of water during the light-dependent reaction. 3. Remember, the electrons lost from the reaction center in photosystem II must be replaced. The splitting of water serves to replace these lost electrons.

Explain the energy flow and conversion of photosynthesis.

chloroplasts "capture" sunlight energy in two ways. Light ”excites” electrons in pigment molecules, and light provides the energy to split water molecules, providing more electrons as well as hydrogen ions. Light Energy to Chemical Energy

Describe how ATP is produced during the light-capturing reactions of photosynthesis.

photophosphorylation

Understand the purpose of the Calvin cycle and how it relates to photosynthesis

This is the light independent portion of the photosynthetic process. ATP from photosystem II provides energy and NADPH from PS I provides a source of hydrogens and high-energy electrons needed to bind the hydrogen to carbon. In the Calvin Cycle three molecules each containing 5 carbons (Ribulose bisphosphate) are joined to 3 carbon dioxide molecules to produce 6 molecules of 3-phosphoglycerate. This reaction is catalyzed by the enzyme rubisco. A series of reactions consumes 6 ATP and 6 NADPH to produce 6 glyceraldehyde 3-phosphate molecules. One of these is used ultimately to produces glucose, the other five are turned back into the original ribulose bisphosphate at a cost of a further 3 ATP molecules.

What is an autotroph?

pine tree….An autotroph[α] ("self-feeding", from the Greek autos "self" and trophe "nourishing") or producer, is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) from simple substances present in its surroundings, generally using energy from light (photosynthesis) or inorganic chemical reactions (chemosynthesis).

What is the reaction for photosynthesis?

In general outline and in effect, photosynthesis is the opposite of cellular respiration, in which glucose and other compounds are oxidized to produce carbon dioxide and water, and to release chemical energy (an exothermic reaction) to drive the organism’s metabolism.

What are the light reactions? What’s their purpose?

Light-dependent reactions 1. Capture energy from sunlight 2. Use the energy and H20 to make ATP and NADPH Light-independent reactions 3. Use ATP and NADPH to make sugars from CO2

What is the Calvin cycle? What is its purpose?

The Calvin cycle is the last step in photosynthesis. The purpose of the Calvin Cycle is to take the energy from photosystem I and fix carbon. Carbon fixation means building organic molecules by adding carbon onto a chain. In order to do this, you have to start with an organic molecule, a starter molecule.

What is chlorophyll? What ranges does it absorb light (what colors of light do they absorb)?

Green pigments found in chloroplast, that absorb light during photosynthesis. absorbs in blue and red regions of visable spectrum

What is light and what are the two ways in which it can be described? What is wavelength &
how does it relate to energy? What is a photon?

Light Is a type of energy electromagnetic radiation Acts both particle-like and wave-like WavelengthThe greater the energy, the larger the frequency and the shorter (smaller) the wavelength. Given the relationship between wavelength and frequency — the higher the frequency, the shorter the wavelength — it follows that short wavelengths are more energetic than long wavelengths. wave or partical…. photon energy packet

What is the antenna complex? What happens to electrons that are in the antenna complex? How is their energy transferred or transformed?

The light-harvesting complex (or antenna complex) is an array of protein and chlorophyll molecules embedded in the thylakoid membrane of plants, which transfer light energy to one chlorophyll a molecule at the reaction center of a photosystem series of chlorophyll

What is the reaction center?

When a chlorophyll molecule is excited in the reaction center, its excited electron is transferred to an electron acceptor. Electromagnetic energy is transformed into chemical energy.

What electron acceptor molecules are involved in photosynthesis?

pheophytin

Know how photosystem I and photosystem II works.

Photosystem II produces A proton gradient that drives the synthesis of ATP Photosystem I yields Reducing power in the form of NADPH Several groups of bacteria have just one of the two photosystems The cyanobacteria, algae, and plants have both

Know the Z scheme

What is photophosphorylation

take light excited electrons used to create hydrogen gradient to create ATP

Where does photosynthesis take place

thylakoid membranes ( in the chloroplast)

Where are photosystems I and II?

thylakoid

Where is the electron transport chain that is involved in photosynthesis?

thylakoid

How does the electron transport chain generate ATP?

via a proton gradient across thylakoid membarane

What is chemiosmosis?

hydrogen protons to make ATP

In addition to proteins, what other molecules must thylakoid membranes possess in order to
harvest light energy?

chloraphyll

What is the structure of chlorophyll a & b?

one has alihide and methal group

Know the chromatography experiment in Chapter 10 and how it works. This is where different
pigments are separated.

…

What causes leaves to change color in the autumn?

chloraphylle a and b die off left with caratanoids

Why do we see certain colors of light? In other words, if given the color of an object, know
which wavelengths are being reflected and which are absorbed

aborb reflect or transmitt

Know the role carotenoids play when it comes to free radicals

Stabilize free radicals Protect chlorophylls from damage

What happens when energy is absorbed by chlorophyll?

produce floresence or undergo resenence

Which wavelengths of light are absorbed the most by plants/the antenna complex?

blue and red

What is NADPH? What is pheophyton? Ferrodoxin? Plastoquinone? Plastocyanin?

NADPHfunctions as a reducing agent similar to NADH produced in cellular resperation. Some of the energy released from these redox reactions is also used to make ATP.Plastoquinone In photosystem 2 PQ transports electrons between molecles like that of ubiquinone in the ETC of cellular resperation. PQ delivers electrons from Photo.2 to the thylakoid.Plastocyanin forms a physical link between photosystem 2 and 1 and shuttles electrons between Photo. 1 and the cytochrome complex.

Where do the electrons that drive photosystem II ultimately come from?

H20 in the thylakoid membrane

What happens to the energy as it passes through photosystem II? Photosystem I?

energy is used to make ATP. NAPD in 2

What is the function of stomata?

Function. The gas exchange that occurs when stomata are open facilitates photosynthesis. Photosynthesis is the process by which plants convert sunlight into usable energy. During photosynthesis, carbon dioxide is taken in from the atmosphere through the stomata and oxygen is released as a waste product.