What is a photosystem complex?

Photosystems are functional and structural units of protein complexes involved in photosynthesis. Together they carry out the primary photochemistry of photosynthesis: the absorption of light and the transfer of energy and electrons. Photosystems are found in the thylakoid membranes of plants, algae, and cyanobacteria.

What is the role of antennae pigments of LHC?

The pigment-binding light-harvesting complex (LHC) proteins of plants and eukaryotic algae are the building blocks of the photosynthetic antenna system. They are responsible for light absorption, energy distribution between the photosystems, and photoprotection.

What is the function of photosystem in photosynthesis?

Photosystems are the functional units for photosynthesis, defined by a particular pigment organization and association patterns, whose work is the absorption and transfer of light energy, which implies transfer of electrons. Physically, photosystems are found in the thylakoid membranes.

How does a photosystem work?

Photosystems are structures within the thylakoid membrane that harvest light and convert it to chemical energy. Each photosystem is composed of several light-harvesting complexes that surround a reaction center.

What are antennae in photosystem Class 11?

Photosystem: In photosystems, the energy collected over a higher range of wavelengths and concentrates it to one molecule called a reaction center which uses the energy to pass one of its electrons on to a series of enzymes. Antenna: The aggregate of different proteins is known an antennae complex.

What is antenna pigment in photosynthesis?

antenna. A pigment with the primary function of capturing the energy from photons and transferring that energy to other pigments within the photosystem. Most chlorophyll molecules function as antennae, with relatively few of the hundreds of chlorophyll molecules carrying out photochemistry in the reaction center.

What are the roles of photosystem 1 and 2?

Photosystem 1: The main function of the photosystem 1 is NADPH synthesis. Photosystem 2: The main function of the photosystem 2 is ATP synthesis and hydrolysis of water.

Which is a role of Photosystem I in the light reactions?

Photosystem I is an integral membrane protein complex that uses light energy to catalyze the transfer of electrons across the thylakoid membrane from plastocyanin to ferredoxin. Ultimately, the electrons that are transferred by Photosystem I are used to produce the high energy carrier NADPH.

What is the role of photosystem 2 in photosynthesis?

Photosystem II is the first link in the chain of photosynthesis. It captures photons and uses the energy to extract electrons from water molecules. As these electrons flow down the chain, they are used to pump hydrogen ions across the membrane, providing even more power for ATP synthesis.

What is the main role of photosystem 2?

The most important function of photosystem II (PSII) is its action as a water-plastoquinone oxido-reductase. At the expense of light energy, water is split, and oxygen and plastoquinol are formed. PSII is an anthropogenic target for many herbicides. There is a unique action of bicarbonate on PSII.

Why do we need an antenna in photosynthesis?

All photosynthetic organisms contain a light-gathering antenna system, which functions to collect light and transfer energy to the reaction center complex where electron transfer reactions take place. These antenna complexes provide a very large absorption cross section for light capture.

What is the function of antennae complex in photosynthesis?

Antenna Complexes for Photosynthesis. The capture of light energy for photosynthesis is enhanced by networks of pigments in the chloroplasts arranged in aggregates on the thylakoids. These aggregates are called antennae complexes.

How effective are antenna proteins in photoprotection of photosystem I?

In vitro experiments on isolated complexes confirmed that depletion of antenna proteins reduced the resistance of isolated Photosystem I particles to high light and that the antenna is effective in photoprotection only upon the interaction with the core complex.

What is the structure of photosystem I?

Photosystem I. The light absorption processes associated with photosynthesis take place in large protein complexes known as photosystems. The one known as Photosystem I contains a chlorophyll dimer with an absorption peak at 700 nm known as P700. Photosystem I makes use of an antenna complex to collect light energy for the second stage…

How does photosystem II collect light energy?

Photosystem II makes use of an antenna complexto collect light energy for the first stages of non-cyclic electron transport. This sketch shows some of the context of Photosystem II in the electron transport processin the thylakoid membrane.