Tag: the origin of cells and cell division

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Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Enzymes concerned with transfer of electrons are

  1. Hydrolase

  2. Dehydrogenase

  3. Transaminase

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

Dehydrogenases catalyze dehydrogenation reactions, which involve addition or removal of electrons. Addition or removal of electrons will lead to reduction or oxidation of substrates. Dehydrogenases are a type of oxidoreductases.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Which one of the following pair is wrongly matched?

  1. Detergents - lipase

  2. Alcohol - nitrogenase

  3. Fruit juice - pectinase

  4. Textile - amylase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This question relates to the industrial applications of enzymes. Alcohol is not produced by the use of nitrogenase. Nitrogenase performs complex functions of nitrogen fixation by bacteria. Alcohol is produced by the fermentation process of sugars carried out by Yeast.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Which one is not an example for hydrolases?

  1. Dehydrogenase

  2. Protease

  3. Amylase

  4. Esterase

  5. Sucrase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dehydrogenases catalyze dehydrogenation reactions which involve addition or removal of electrons. The addition or removal of electrons will lead to reduction or oxidation of substrates. Dehydrogenases are a type of oxidoreductases. Some of the important hydrolases includes amylases, sucrase, lactase, maltase, protease, esterase etc.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Most of the biochemical reactions differ from those occurring in the non-living world in ________________.

  1. Requiring energy

  2. Releasing energy

  3. Being enzymatic

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

Biochemical reactions are unique because they are mediated by enzymes, which lower activation energy and increase reaction rates under physiological conditions.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Lactic dehydrogenase (LDH) which catalyzes pyruvate to lactate is an example of

  1. Apoenzyme

  2. Antienzyme

  3. Isoenzyme

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

Some enzymes have several molecular forms, example: 16 for $\alpha$-amylase and 5 for lactate dehydrogenase (LDH). They are called as isoenzymes or isozymes. They differ in substrate affinity, maximum activity and regulatory properties.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Enzymes which act similarly are called as

  1. Isoenzyme

  2. Cofactor

  3. Coenzymes

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Isoenzymes are enzymes that catalyze identical chemical reactions but are composed of different amino acid sequences. They are sometimes referred to as isozymes. Isoenzymes are produced by different genes. They occur in many tissues throughout the body and are important for different developmental and metabolic processes. Alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) are examples of isoenzymes.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Hexokinase (Glucose $+$ ATP $\longrightarrow$ Glucose 6-P $+$ ADP) belongs to the category

  1. Transferases

  2. Lysases

  3. Oxidoreductases

  4. Isomerases
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Transferase is an enzyme which transfers a group from one molecule to another molecule. Hexokinase is the enzyme which transfers one phosphate from ATP to glucose and forms glucose 6-phosphate.

(Glucose ++ ATP ⟶⟶ Glucose 6-P ++ ADP)
Thus, the correct answer is A.

Multiple choice biology enzymes classification of enzyme enzymes classification and cofactors the origin of cells and cell division

Enzymes functional in cells are called

  1. Endoenzymes

  2. Exoenzymes

  3. Apoenzymes

  4. Isoenzymes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Endoenzyme is the cells which function inside the cell. It is also known as intracellular enzymes. It helps in the catalysis of the intracellular metabolic reaction. 

Exoenzymes are the enzymes which function outside the cell.
Isoenzyme is also known as isozyme. When the two enzymes differ in amino acid sequence but catalyze the same chemical reaction they are known as isoenzyme. They are two different molecular form of the enzyme.
Enzymes are proteins which help to catalyze the biochemical reaction. The enzyme has a protein part which is not active is known as apoenzyme.
So, the correct answer is option A.