IGCSE Biology Paper-1: Specimen Questions with Answers 202 - 203 of 208
Question 202
Question
MCQ▾The diagram shows different type of venation in monocot and dicot leaf.
What does P and Q represent?
Choices
Choice (4) | |
---|---|
a. | P-reticulate venation, Q-reticulate venation |
b. | P-reticulate venation, Q-parallel venation |
c. | P-parallel venation, Q-parallel venation |
d. | P-parallel venation, Q-reticulate venation |
Answer
d.Explanation
Venation is the arrangement of the veins and the veinlets in a leaf. It is of two types:
- Reticulate Venation: - The veins are arranged in a net like manner, e. g. , Dicots.
- Parallel Venation: - The veins are arranged parallel to each other, e. g. , Monocots.
Question 203
Question
MCQ▾The diagram of glycogen which is storage carbohydrate in animals is shown.
What X represents which is a monomer unit?
Choices
Choice (4) | |
---|---|
a. | Glucose |
b. | Fructose |
c. | Starch |
d. | Lactose |
Answer
a.Explanation
Polysaccharides
- They are formed by joining of Monosaccharides (Monomers) by Glycosidic bonds between 1 - 4 carbon atoms. (In a polysaccharide chain the right end is called ‘reducing end’ and the left end is called non-reducing end)
- They are non-reducing and mostly insoluble in water.
Types of Polysaccharides
- Storage polysaccharides – e. g. Glycogen and Starch
- Structural polysaccharides – e. g. Cellulose and Chitin
Glycogen
It is present in animals (also called animal starch) . It is a branched chain compd. and has about 30 α-glucose units. It gives ‘red colour’ with iodine solution.