Page 28 - E-Biology Sec.2 2024-2025 U1_Handy

Characteristics of enzymes:

1- Specific: each one accelerates only 1 type of reactions, depending on the structure
of the substrate and the nature of the enzyme.

2- They don’t affect the products: increasing the rate of reaction till it reaches the
equilibrium state.

3- Some have a reversible effect: depending on the concentration of the reactants.

4- The degree of enzyme’s activity depends on: temperature & PH of the medium.
5- Some are secreted in an inactive state then are activated by specific substance:

Secreted by stomach

Structure of the digestive system

Most organs of the digestive system lie in the abdominal cavity.

The digestive Accessory
(alimentary) canal (Associated) glands

1- Mouth 1- Salivary glands
2- Pharynx 2- Liver
3- Oesophagus 3- Pancreas
4- Stomach
5- Small intestine
6- Large intestine
7- Rectum
8- Anus

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First Term