Tag: microbodies

Questions Related to microbodies

Glyoxysomes occur in

  1. Both plant and animal cells

  2. Plant cells only

  3. Animal cells only

  4. All types of cells


Correct Option: B
Explanation:

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 useful in

  1. Converting sugars to fats

  2. Converting fats to sugars

  3. Deamination and converting amino acids to fatty acids

  4. Amination and changing fatty acids to amino acids


Correct Option: B
Explanation:
  • 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'.

Some of the enzymes, which are associated in converting fats into carbohydrates, are present in

  1. Liposomes

  2. Golgi bodies

  3. Microsome

  4. Glyoxysomes


Correct Option: D
Explanation:

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.

In 1967, R. W. Breidenbach and H. Beevers discovered microbodies in fat storing cells of germinating seed known as

  1. Lomasomes

  2. Mesosomes

  3. Peroxisomes

  4. Glyoxysomes


Correct Option: D
Explanation:

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.

The following can be called as plant lysosomes.

  1. Spherosomes

  2. Aleurone grains

  3. Vacuoles

  4. All of the above


Correct Option: A
Explanation:

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.

Spherosomes take part in the synthesis of?

  1. Fat

  2. Carbohydrate

  3. Protein

  4. None of these


Correct Option: A
Explanation:
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 of fat'.

Unique to lysosomes in comparison to peroxisomes is that

  1. Peroxisomes lack lytic enzymes.

  2. Lysosomal membranes show latency which peroxisome lack.

  3. Peroxisomes cannot be found in animal tissue.

  4. All of the above


Correct Option: A
Explanation:

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.

Match the following.

Column I Column II
Microbody Function
I) Sphaerosomes a) $H _2O _2\rightarrow H _2O^+$ oxygen
II) Peroxisomes b) acts like elaioplasts
III) Glyoxysomes c) Helps in yolk formation
IV) Lomasomes d) Cell-elongation
V) Transosomes e) Fats $\rightarrow$ Carbohydrates
f) Radiant energy $\rightarrow$ Chemical energy
  1. I-a, II-b, III-d, IV-c, V-e

  2. I-b, II-c, III-a, IV-d, V-f

  3. I-b, II-a, III-e, IV-d, V-c

  4. I-c, II-a, III-b, IV-d, V-e


Correct Option: A

Animal cell is different from plant cell in lacking 

  1. CaCO$ _3$ crystals in cytoplasm

  2. Sphaerosomes

  3. Pyrenoids and chloroplast

  4. All of the above


Correct Option: D
Explanation:

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.

F$ _1$ subunit of oxysome is called as

  1. Head 

  2. Lineage

  3. Base

  4. Filament


Correct Option: A
Explanation:

Oxysomes are the structures which are present on the surface of the folded inner membrane of the mitochondria. They are also called f0-f1 particles or ATP synthase. They play the most important role in the formation of energy for the functioning of the cell. The F1 subunit of the oxysomes is refered as the head.