Microbodies - class-XI

Spherosomes are membrane covered small spherical organelles which synthesize and store fats. They are covered with a single half unit membrane.

Endomembrane system of a eukaryotic cell is a membrane system that involves flow of membranes from one component to another by means of small membrane vesicles. The endomembrane system of a eukaryotic cell consists of endoplasmic reticulum, Golgi apparatus, lysosomes and plasma membrane.

Spherosomes are membrane covered small spherical organelles which synthesize and store fats. They develop from endoplasmic reticulum. In some plants, spherosomes have lysosomal activity, e.g., maize root tip.

Peroxisomes are microbodies which have enzymes for peroxide metabolism. They include :
(a) Peroxide producing oxidative enzymes like peroxidase, urate oxidase or uricase, amino acid oxidase.
(b) Peroxide destroying enzymes like catalase. 

Peroxisomes are single membrane covered cell organelles which take part in oxidation reactions other than those of respiration. Peroxisomes are microbodies which have enzymes for peroxide biosynthesis like peroxidases, amino acid oxidase and peroxide destruction like catalase.

Peroxisomes are microbodies which have enzymes for peroxide metabolism. They include : (a) Peroxide producing oxidative enzymes like peroxidase, urate oxidase or uricase, amino acid oxidase and (b) peroxide destroying enzymes like catalase.
Peroxisomes occur widely in animals cells, protists, fungi, higher plants but quite common in photosynthetic cells. In mesophyll cells, peroxisomes interact with chloroplasts, and mitochondria to take part in photorespiration.

Peroxisomes are microbodies which have enzymes for peroxide metabolism. They include :

Glyoxysomes are microbodies which occur only in fat rich plant cell, where they take part in $\beta$-oxidation of fats and perform glyoxylate cycle. 

• Glyoxysomes are a type of peroxisomes found in plants and few filamentous fungi.
  
• They are particularly found in fat storage tissues of germinating seeds (peanuts, soybeans etc.) in plants.
• It helps in fatty acid oxidation, glyoxylate cycle and gluconeogenesis.
  
• They contain enzymes (citrate synthase, isocitrate lyase and malate synthase etc.) which are responsible for beta-oxidation of fatty.
• It also contains enzymes which produce intermediate products for the synthesis of sugars by gluconeogenesis.
• So, the correct answer is 'Converting fats to sugars'.

Glyoxysomes are microbodies which occur only in fat rich plant cell, where they take part in $\beta$-oxidation of fats and perform glyoxylate cycle. Glyoxysomes also possess catalase enzyme. In fat storing plant cells, first fats are converted to carbohydrates which are then metabolised.

Glyoxysomes were discovered by Breidenbach, 1967 and Beevers, 1963. Glyoxysomes are microbodies which occur only in fat rich plant cells where they take part in $\beta$-oxidation of fats and perform glycolate cycle. Glyoxysomes possess catalase enzyme.

Spherosomes are single half unit membrane covered small spherical organs which synthesize and store fats. They develop from endoplasmic reticulum. In some plants, spherosomes have lysosomal activity, e.g., spherosomes found in maize root tip.

Peroxisomes are microbodies which have enzymes for peroxide biosynthesis. They include peroxide producing enzymes like peroxidase, urate oxidase, amino acid oxidase and peroxide destroying enzyme catalase. Lysosomes are small vesicles containing hydrolysing enzymes and surrounded by single membrane. They are formed by Golgi apparatus and contain some 60 different types of hydrolytic enzymes eg nucleases, proteases, lipases, phosphatases etc. for digestion of various materials.

Matching: I-b (Sphaerosomes store fats/elaioplasts), II-a (Peroxisomes handle H2O2), III-e (Glyoxysomes convert fats to carbohydrates), IV-d (Lomasomes involved in cell wall/elongation), V-c (Transosomes involved in yolk formation). Option A matches these correctly.

Cell Inclusions are non-living substances in plant cells. They are of four categories - reserve food, excretory material, pigment and minerals. Due to their presence, a cell may become different from other surrounding cells. It is then called as an idioblast. Calcium carbonate occurs as a mass of crystals around a cellulose core to form cystolith e.g., leaf hypodermis of Banyan tree. Spherosomes are single half unit membrane covered small organelles in plants which synthesize and store fats. They develop from ER. In some plants, spherosomes have lysosomal activity. e.g., maize root tip. Chloroplasts are green plastids which take part in photosynthesis and temporary or permanent storage of starch. Pyrenoids are food storage bodies within the chloroplasts. All of the above mentioned structures are not found in an animal cell.

Spherosomes are single half unit membrane covered small spherical organelles (0.5 to 1.0 micrometer) which synthesize and store fats. Hence, spherosomes are also called as liposomes. Liposome term specifically means vesicles having fat or fat droplets. Spherosomes develop from endoplasmic reticulum. In some plants, spherosomes have lysosomal activity, e.g., maize root tip.

Peroxisomes are single membrane bounded organelles found in nearly all eukaryotic cells. Rest of three are Double membrane.

Peroxisomes are microbodies which have enzymes for peroxide biosynthesis. They include peroxide producing oxidative enzymes like peroxidase, urate oxidase or uricase (hence, peroxisomes are also called as uricosome), amino acid oxidase and peroxide destroying enzymes catalase. Peroxisomes occur widely in animal cells, protists, fungi, eukaryotic algae, bryophytes, pteridophytes and higher plants.

Spherosomes are single half unit membrane covered small spherical organelles which synthesize and store fats. They develop from endoplasmic reticulum. In some plants, spherosomes have lysosomal activity,e.g., maize root tip.

Xenobiotics are foreign compounds such as drugs and toxins are detoxify mainly in peroxisomes.

Glyoxysomes are microbodies which occur only in fat rich plant cells where they take part in $\beta$-oxidation of fats and perform glyoxylate cycle. Glyoxysomes characteristically possess catalase enzyme. The castor endosperm stores fat which is metabolised through glyoxysomes. Glyoxysomes will channel fats into krebs cycle through $\beta$-oxidation.

Spherosomes are single half unit membrane covered small spherical organelles which synthesize and store fats. They develop from smooth endoplasmic reticulum. Smooth endoplasmic reticulum lacks ribosomes and occurs in cells engaged in producing large quantity of lipids.

Glyoxysomes are microbodies which occur only in fat rich plant cells where they take part in $\beta$-oxidation of fats and perform glyoxylate cycle. Glyoxysomes possess catalase enzyme.

The peroxisomes are associated with the phenomenon of photorespiration and degradation of H$ _2$O$ _2$. Certain enzymes within the peroxisome, by using molecular oxygen, remove hydrogen atoms from specific organic substrates, in an oxidative reaction, producing hydrogen peroxide.
Photorespiration involves a complex network of enzyme reactions that exchange metabolites between chloroplasts, leaf peroxisomes and mitochondria.

Sphaerosomes are single membrane bound organelles which takes part in storage and synthesis of fats. They were discovered by Perner (1953). Sphaerosomes are spherical bodies with a diameter of about 0.5-1 mm. They contain granular contents, rich in lipids but also have some proteins. Some proteins are probably enzymatic and take part in the synthesis of fat. But they are not involved in photorespiration.

Peroxisomes contain oxidases. A major function of the peroxisome is the breakdown of very long chain fatty acids through $\beta$-oxidation. In animal cells, the very long fatty acids are converted to medium chain fatty acids, which are subsequently shuttled to mitochondria where they are eventually broken down to carbon dioxide and water.

Catalases and oxidases are found in peroxisomes. Peroxisomes contain oxidative enzymes, such as catalase, D-amino acid oxidase, and uric acid oxidase. A major function of the peroxisome is the breakdown of very long chain fatty acids through $\beta$-oxidation. 

Glyoxysomes are specialized peroxisomes found in plants, particularly in the fat storage tissues of germinating seeds and also in filamentous fungi. As in all peroxisomes, in glyoxysomes the fatty acids are hydrolyzed to acetyl-CoA by peroxisomal-oxidation enzymes. Besides peroxisomal functions, glyoxysomes possess additionally the key enzymes of glyoxylate cycle which accomplish the glyoxylate cycle bypass. Thus, glyoxysomes contain enzymes that initiate the breakdown of fatty acids and additionally possess the enzymes to produce intermediate products for the synthesis of sugars by gluconeogenesis. The seedling uses these sugars synthesized from fats until it is mature enough to produce them by photosynthesis. Glyoxysomes also participate in photorespiration and nitrogen metabolism in root nodules.

Glyoxysomes are specialized peroxisomes found in plants, particularly in the fat storage tissues of germinating seeds and also in filamentous fungi. As in all peroxisomes, in glyoxysomes the fatty acids are hydrolyzed to acetyl-CoA by peroxisomal oxidation enzymes. Besides peroxisomal functions, glyoxysomes possess additionally the key enzymes of glyoxylate cycle which accomplish the glyoxylate cycle bypass. Thus, glyoxysomes contain enzymes that initiate the breakdown of fatty acids and additionally possess the enzymes to produce intermediate products for the synthesis of sugars by gluconeogenesis. The seedling uses these sugars synthesized from fats until it is mature enough to produce them by photosynthesis. Glyoxysomes also participate in photorespiration and nitrogen metabolism in root nodules.

In plants the glyoxylate cycle occurs in special peroxisomes which are called as glyoxysomes. The glyoxylate cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrates. This cycle allows seeds to use lipids as a source of energy to form the shoot during germination. The seed cannot produce biomass using photosynthesis because of lack of an organ to perform this function. The lipid stores of germinating seeds are used for the formation of the carbohydrates that fuel the growth and development of the organism.

Spherosomes, also referred to as lipid bodies or oleosomes, are vesicles that stores triacylglycerol in the form of oil (during seed development). They are surrounded by a phospholipid monolayer - derived from ER. It is the cell organelle responsible for synthesis of cutin and wax. 

Peroxisomes contain enzymes like catalase that break down hydrogen peroxide, a toxic byproduct of metabolic processes, into water and oxygen.

Endomembrane system is a membrane system of a eukaryotic cell that involves flow of membrane from one component to another by means of small membrane vesicles. 

The nucleus is the double membrane bound organelle of eukaryotic cells that serve to house genetic material. The cell wall is the rigid structure present outside the cell membrane of plants, fungi, algal and microbial cells. Being rigid in composition, it provides mechanical support, help maintains the cell shape and prevent lysis of the cell. Lysosomes, present in the cytoplasm, are the suicidal bags of cell that digest and remove the wear and tear organelles and molecules from the cell. Photorespiration is oxidation of RuBP, rather than carboxylation, by enzyme RUBISCO and formation of 2-phosphoglycolate. Dephosphorylation of 2 phosphoglycolate forms glycolate which in turn enters peroxisomes and is then transaminated to glycine. Condensation of two glycine molecules to form serine and carbon dioxide by enzyme glycine decarboxylase takes place in mitochondria. Serine again enters peroxisomes and is converted to hydroxypyruvate and then to glycerate. The glycerate reenters the chloroplasts and is phosphorylated to enter Calvin cycle. Thus, the correct answer is option A.

Sphaerosomes are detected with the help of Sudan black. Sphaerosomes are vesicles that store triacylglycerol in the form of oil and surrounded by phospholipid monolayer. It is produced by an endoplasmic reticulum. It is also responsible for the synthesis of cutin and wax.

Glycolate cycle, also known as C$ _2$ cycle, is a complex metabolic pathway, that takes place in chloroplasts, mitochondria and peroxisomes of plant cells and is responsible for the formation of the amino acids, serine and glycine from non-phosphorylated intermediates of the carbon reduction cycle of photosynthesis.

Sudan stains have high affinity for fats, lipids, triglycerides and lipoprotein. Hence, when a cell is exposed to Sudan stain, it becomes attached to spherosomes because spherosomes are membrane covered small spherical organelles which synthesize and store fats.

Peroxisomes are present in the photosynthetic mesophyll cells of leaves. They play an important role in photorespiration. They maintain redox balance in cells and play a role in plant immune defence. Thus the correct answer is option C.

• Sphaerosome is a cellular organelle enclosed by a single membrane which is only found in plant cells.
• It helps in storage and synthesis of lipid.
• They are formed from the endoplasmic reticulum.
• All the other cellular organelle nucleus, mitochondria and plastids are enclosed by a double membrane.
• So, the correct answer is 'Spherosomes'.

• Enzymes associated with converting fats to carbohydrates are located in Glyoxysomes.
• Glyoxysomes are a type of peroxisomes found in plants and few filamentous fungi.
  
• They are particularly found in fat storage tissues of germinating seeds (peanuts, soybeans etc.) in plants.
• They contain enzymes (citrate synthase, isocitrate lyase and malate synthase etc.) which are responsible for beta-oxidation of fatty acids,
• It helps in fatty acid oxidation, glyoxylate cycle and gluconeogenesis.
• So, the correct answer is 'Glyoxysomes'.

• Glyoxysomes are a type of peroxisomes found in plants and few filamentous fungi.
  
• They are particularly found in fat storage tissues of germinating seeds (peanuts, soybeans etc.) in plants.
•  They contain enzymes (citrate synthase, isocitrate lyase and malate synthase etc.) which are responsible for beta-oxidation of fatty acids,
• It helps in fatty acid oxidation, glyoxylate cycle and gluconeogenesis.
• So, the correct answer is 'Fats'.

• Spherosomes or oleosomes are small cellular organelles enclosed by a single membrane that is responsible for the storage and synthesis of lipid. 
• They are obtained from the endoplasmic reticulum, they are surrounded by a single phospholipid monolayer and are found in only plant cells.
•  So, the correct answer is 'Involved in photorespiration'.

• Glyoxysome is a type of peroxisome found in plants cells.
• It is mainly found in the cells of fat storing tissues of germinating seeds and is also present in filamentous fungi.
• The growing seed or the seedling utilizes the sugars synthesized from fats until it attains maturity (produce them by photosynthesis after maturity).
• So, the correct answer is 'Glyoxysome'.

• In plant cells, peroxisomes are associated with photorespiration.
  
• Peroxisomes (microbody) are small organelle which contains reducing and oxidising enzyme catalase.
  
• It helps in the breakdown of long chain fatty acids through beta-oxidation and converts them into to medium chain fatty acids, which are subsequently broken down to carbon dioxide and water in the mitochondria (photorespiration).
• So, the correct answer is 'Photorespiration'.
  

• A lysosome is a single membrane-bound organelle which contains digestive enzymes that digest excess or worn out organelles, food particles, engulfed viruses or bacteria and macromolecules.
• The peroxisome is a single membrane-bound organelle which contains oxidative enzymes and is responsible for lipid production and oxidation reactions within the cell.
• Whereas, mitochondria is a double membrane-bound organelle and is known as the powerhouse of the cell which is present in all eukaryotic cells.
• So, the correct answer is 'Both peroxisomes and lysosomes'.

• The peroxisome is a single membrane-bound organelle which contains oxidative enzymes and is responsible for lipid production and oxidation reactions within the cell.
  
• Peroxisomes are present in the photosynthetic cells of green plants (palisade cells of C3 plants and bundle sheath cells of C4 plants).
• So, the correct answer is 'Bundle sheath'.

• Spherosomes or oleosomes can be defined as small cellular organelles found in plant cells that are enclosed by a single membrane. 
• It is mainly responsible for the storage and synthesis of lipid. 
• It was discovered by Perner in the year 1953.
• They are obtained from the endoplasmic reticulum and are surrounded by a phospholipid monolayer.
  
• So, the correct answer is 'Perner'.

• Spherosomes or oleosomes can be defined as small cellular organelles found in plant cells that are enclosed by a single membrane. 
  
• It is mainly responsible for the storage and synthesis of lipid. 
  
• The lipid content in spherosomes is 98% and proteins content is only 2 %.
  
• They are obtained from the endoplasmic reticulum and are surrounded by a phospholipid monolayer.
  
• So, the correct answer is 'Synthesis and storage of fat'.

• Microbodies or cytosomes can be defined as cellular organelle found in the plant cells, protozoans and animal cells (liver and kidney cells).
  
• The different types of microbodies present within a cell are peroxisomes, glyoxysomes, glycosomes and hydrogenosomes.
• The main function of microbodies is oxidation of fatty acids, amino acids, purines and alcohol (liver cells) which requires significant amounts of oxygen.
• Mitochondria are double membrane-bound cellular organelles which are known as the powerhouse of the cell.
• It creates energy-rich molecules (ATP) for the cell by utilizing oxygen. 
  
• So, the correct answer is 'Using oxygen'.

• Spherosomes or oleosomes can be defined as small cellular organelles found in plant cells that are enclosed by a single membrane. 
  
• It is mainly responsible for the storage and synthesis of lipid. 
• They arise from the endoplasmic reticulum and are enclosed by a phospholipid monolayer.
  
• So, the correct answer is 'E.R'.

A. Spherosomes or oleosomes can be defined as small cellular organelles found in plant cells that are enclosed by a single membrane. 

• The enzyme catalase occurs in Peroxisome and glyoxysome.
• The enzyme catalase is found all living organisms such as bacteria, plants, and animals.
  
• Its main function is to catalyze the breakdown of hydrogen peroxide into water and oxygen and thus, protects the cell from oxidative damage from reactive oxygen species.
• The peroxisome is a single membrane-bound organelle which contains oxidative enzymes and is responsible for lipid production and oxidation reactions within the cell.
  
• Similarly, glyoxysome is specialized peroxisome which is found in fat storage tissues of germinating seeds.
• So, the correct answer is 'Peroxisome and glyoxysome'.

• The peroxisome is a single membrane-bound organelle which contains oxidative enzymes and is responsible for lipid production and oxidation reactions within the cell.
  
• They were discovered by Christian de Duve (Belgian cytologist) in the year 1967.
• So, the correct answer is 'De Duve'.

Peroxisomes are involved in the breakdown of H2O2, the utilization of oxygen in oxidative reactions, and the degradation of various toxic molecules, making all listed functions correct.

Recent research into the evolutionary origin of peroxisomes suggests they may have evolved from an endosymbiotic relationship with actinobacteria.

Gluconeogenesis, specifically the glyoxylate cycle, occurs in glyoxysomes, which allow plants to convert stored fats into sugars for energy during germination.

Matching: (a) Endoplasmic reticulum-v (detoxification), (b) Sphaerosome-iii (lipid synthesis/storage), (c) Dictyosomes-i (stack of cisternae), (d) Peroxisomes-iv (photorespiration), (e) Elaioplasts-ii (store oil). Option A matches these correctly.

Peroxisome  are surrounded by only a single membrane, and they do not contain DNA or ribosomes. Like mitochondria and chloroplasts, however, peroxisomes are thought to acquire their proteins by selective import from the cytosol. But because they have no genome, all of their proteins must be imported.

• The peroxisome is a single membrane-bound organelle which contains oxidative enzymes and is responsible for lipid production and oxidation reactions within the cell.
  
• It helps in the oxidation of fatty acids, amino acids, purines and alcohol (liver cells) which requires significant amounts of oxygen.
• So, the correct answer is 'Peroxisome'.

Peroxisomes are cytoplasmic organelles that play a central role in break down of fatty acids and other oxidation reactions in the cell.

 Peroxisomes are cell organelles that are involved in lipid or triglyceride metabolism. They are bound by a single membrane and are present in the cytosol.

Glyoxysomes are specialized peroxisomes found in plants that contain enzymes for the glyoxylate cycle, which is essential for fat metabolism during seed germination.

Peroxisomes are membrane-bound organelles in eukaryotes. Photorespiration is a light-dependent process that takes place in mitochondria in which oxygen is absorbed and carbon dioxide is released. It is counter-productive to photosynthetic carbon dioxide fixation and decreases plant productivity. But it also provides protection against conditions caused by high light intensity, drought, and salinity.  Thus the correct answer is option A.

Peroxisomes are found in photosynthetic cells and perform photorespiration. They also take part in lipid metabolism. Lysosomes are the cell's garbage disposal system and not the peroxisomes.

Glyoxysomes are microbodies which contain enzymes for $\beta$-oxidation of fatty acids and glyoxylate pathway. They are considered to be special peroxisomes. They occur abundantly in gerrminating endosperm cells of oil seeds.