Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Peroxisomes have which of the following enzymes?

  1. Hydrolases

  2. Oxidases

  3. Transferases

  4. Lyases
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Fat is stored in which of the following organelle?

  1. Lysosome

  2. Sphereosome

  3. Microsome

  4. Peroxisome
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which of the following organelle contain enzymes that detoxify xenobiotics ?

  1. Rough endoplasmic reticulum

  2. Endosomes

  3. Peroxisomes

  4. Lysosomes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

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

So, the correct answer is 'peroxisomes'

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

In which on of the following would you expect to find glyoxysomes?

  1. Endosperm of wheat

  2. Endosperm of castor

  3. Palisade cells in leaf

  4. Root hairs
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Spherosomes found in lipid storing cells originate from

  1. Mitochondria

  2. SER

  3. RER

  4. Golgi complex
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

The function of glyoxysomes is 

  1. Protein metabolism

  2. Carbohydrate metabolism

  3. Fat metabolism

  4. Protein synthesis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

The peroxisomes are associated with the phenomenon of

  1. Oxidative anabolism
  2. Degradation of H$ _2$O

  3. Anaerobic respiration
  4. Photorespiration and degradation of H$ _2$O$ _2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which is not true about sphaerosomes?

  1. Involved in photorespiration

  2. Arise from E.R.

  3. Related to fat metbolism

  4. Single membane bound
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Peroxysomes contain

  1. Hydrolytic enzyme

  2. Transferase

  3. Isomerase

  4. Oxidising enzyme (Oxidase)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which of the following enzymes are found in matrix of peroxisomes?

  1. NADH cytochrome reductase

  2. Glyoxidases and malate dehydrogenase

  3. Acid phosphatases and isocitric lysase

  4. Catalases and oxidases
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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.