Class 9th, Grade ix, biology notes chapter no 6 enzymes short questions, long questions, definitions, meaning History, and types of Enymes, Pdf Download All kpk boards.
Unit 6 Enzymes Biology KPK Grade ix
An enzyme is one such catalyst which is commonly known as the biological catalyst. Enzymes present in the living organisms enhance the rate of reactions which take place within the body. Biological catalysts, enzymes, are extremely specific that catalyze a single chemical reaction or some closely associated reactions.
Q1: Define metabolism and its types?
Ans: Metabolism:
Meaning:
The word metabolism is derived from a Greek word meaning “Change”
History:
Concept of metabolism was first of all given by Ibn-e-Nafees.
Definition:
The sum of all Chemical reactions that takes place in living organisms is called Metabolism.
Types of Metabolism:
There are two types of metabolism.
i. Anabolism
ii. Catabolism
Q3: Write the characteristics of enzymes.
Ans: Characteristics of enzymes:
- i. Enzymes are globular proteins in nature and are secreted by cells.
- ii. The enzymes functions as catalyst and increase the rate of chemical reaction.
- iii. They lower the activation energy of reactions.
- iv. Enzymes are usually very specific for the type of reaction and for the nature of their substrate.
- v. A small amount of enzyme can bring change in a large amount of substrate.
- vi. Enzymes are sensitive to change in pH of the substrate.
- vii. Some enzymes work inside the cells called intracellular enzymes. Like mitochondrial enzymes while some enzymes like pepsin work in stomach.
- viii. Enzymes activity can also be regulated by inhibitor and activators.
