Question

Which type of enzyme occurs in lysosomes?
A. Lyase
B. Ligase
C. Hydrolase
D. Transferase

Answer 1

Hint: Lysosomes are single membraned organelle mainly found in animals. These are commonly called ‘suicidal bags’ of cells. They are a part of the Endo-membrane system. They help in digestion of molecules because they have hydrolytic enzymes. The hydrolytic enzymes present in lysosomes are inactive and require an acidic \[pH\]\[\left( {5.5} \right)\] to get activated.

Complete answer:
Lyases: These are the enzymes that catalyse the removal of certain groups and form a double bond in the substrate.
Option (a) is incorrect.
Ligase: They link together two compounds, ex. DNA ligase.
Option (b) is incorrect.
Hydrolase: These catalyse hydrolysis (breaking of bond by addition of water) of ester, ether, peptide, glycosidic bond, ex. digestive enzymes.
Option (c) is correct.
Transferase: They catalyse transfer of a group (other than H) from one compound to another, ex. transaminase, peptidyl hydrogenase.
Option (d) is incorrect.

Hence the correct answer is option (c).

Note:
Lysosomes are polymorphic in nature i.e., they have many morphological, physiological states.
1. Primary lysosome: these are newly formed and have inactive enzymes.
2. Secondary lysosomes/ Heterophagosome: they are formed when primary lysosomes fuses with food vacuole, the enzymes become active and digest the complex food molecules.
3. Tertiary lysosome: these are the residual bodies with waste food material. Its content exits the cell through exocytosis.
4. Autophagosomes: These digest the dead organelles of the cell and are referred to as the dustbin of the cell.
They help in metamorphosis of frogs by digesting its tail in the tadpole stage.