Lecture 54 of 175: Microbodies: Peroxisomes & Glyoxysomes (12 mins) | Indian Council of Agricultural Research (ICAR) AIEEA UG Biology | Complete Video Course 175 Lectures [105 hrs : 16 mins]

Details

Microbodies (microsomes) are small, almost spherical organelles (diameter typically 1 – 2 micrometers) bounded by a single membrane. There are two main types: peroxisomes and glyoxysomes. Peroxisomes occur in green cells and contain oxidases – especially glycolate oxidase, which catalyzes a reaction important in photorespiration.

Function:

1. Biochemical Reactions:
2. Enzymatic Activity:
3. Photorespiration in Plants:
4. Detoxification:

Peroxisome:

1. Discovery: Identified by Christian de Duve in 1965. Discovered using the fractionation method.
2. Distribution: Present in cells from both plants and animals.
3. Origins: 70 – 100 peroxisomes in photosynthetic cells.
4. Variability in Structure: Vary in size, shape, and diameter.
5. Oxidative Enzymes: Contain oxidative enzymes such as urate oxidase, hydroxy acid oxidase, and catalase.
6. Identification: Larger peroxisomes can be observed in hepatocytes.

Function:

1. Membrane-Bound Organelle:
2. Oxidative Processes:
3. Enzymatic Conversion:
4. Plant Photorespiration:

Glyoxysomes

Discovery:

Discovered by Breidenbach in 1967.

Specialized Peroxisomes:

Occurrence: Plants And Fungi

Size and Presence:

Considered the largest microbodies.

Present in cells of some fungi and in fatty seeds during germination (e. g. , castor, groundnut).