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Lecture

Photosynthesis: An Overview

Description

This lecture covers the process of photosynthesis, focusing on the origin, types, pigments, and structures associated with it. It explains the evolution of oxygenic photosynthesis and the characteristics of different phototrophs, including cyanobacteria, purple sulfur bacteria, and green bacteria.

Official source

Ontological neighbourhood

Biology

Cell biology: Photosynthesis

Related concepts (32)

Anoxygenic photosynthesis

Anoxygenic photosynthesis is a special form of photosynthesis used by some bacteria and archaea, which differs from the better known oxygenic photosynthesis in plants in the reductant used (e.g. hydrogen sulfide instead of water) and the byproduct generated (e.g. elemental sulfur instead of molecular oxygen). Several groups of bacteria can conduct anoxygenic photosynthesis: green sulfur bacteria (GSB), red and green filamentous phototrophs (FAPs e.g. Chloroflexia), purple bacteria, acidobacteriota, and heliobacteria.

Photosynthesis

Photosynthesis (ˌfoʊtəˈsɪnθəsɪs ) is a biological process used by many cellular organisms to convert light energy into chemical energy, which is stored in organic compounds that can later be metabolized through cellular respiration to fuel the organism's activities. The term usually refers to oxygenic photosynthesis, where oxygen is produced as a byproduct, and some of the chemical energy produced is stored in carbohydrate molecules such as sugars, starch and cellulose, which are synthesized from endergonic reaction of carbon dioxide with water.

Thylakoid

Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis. Thylakoids consist of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as grana (singular: granum). Grana are connected by intergranal or stromal thylakoids, which join granum stacks together as a single functional compartment. In thylakoid membranes, chlorophyll pigments are found in packets called quantasomes.

Photosynthetic reaction centre

A photosynthetic reaction center is a complex of several proteins, pigments and other co-factors that together execute the primary energy conversion reactions of photosynthesis. Molecular excitations, either originating directly from sunlight or transferred as excitation energy via light-harvesting antenna systems, give rise to electron transfer reactions along the path of a series of protein-bound co-factors. These co-factors are light-absorbing molecules (also named chromophores or pigments) such as chlorophyll and pheophytin, as well as quinones.

Cyanobacteria

Cyanobacteria (saɪˌænoʊbækˈtɪəri.ə), also called Cyanobacteriota or Cyanophyta, are a phylum of gram-negative bacteria that obtain energy via photosynthesis. The name cyanobacteria refers to their color (), which similarly forms the basis of cyanobacteria's common name, blue-green algae, although they are not usually scientifically classified as algae. They appear to have originated in a freshwater or terrestrial environment.

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Photosynthesis: Pigments and Energy Transfer in Microorganisms

Explores photosynthesis in microorganisms, focusing on pigments and energy transfer mechanisms.

Anoxygenic Photosynthesis

Explores anoxygenic photosynthesis, redox potential, cyclic electron flow, ATP generation, green sulfur bacteria, chlorosomes, and prokaryotic phototroph diversity.

Photosynthesis: Anoxygenic & Oxygenic

Explores anoxygenic photosynthesis in purple bacteria, their cyclic electron flow, and the evolution of oxygenic photosynthesis through endosymbiosis.

Oxygenic Photosynthesis

Explains oxygenic photosynthesis, characteristics of phototrophs, pigments, and cyanobacteria's role as primary producers.

Photosynthesis: Oxygenic Process