PHASE 2
Subject: Biology
Class: Inter part 2 Biology
Time allowed: 2 hours
lecturer: Maliha Nawaz
Marks : 30
Section A
Multiple choice questions (2)
1) The depletion in the ozone layer is caused by
a) Nitrous oxide b) methane c) chlorofluorocarbons d) carbon dioxide
2) It is involved in sleeping and awakening
a) Hippocampus b) Cerebellum c) Brain Stem d) Thalamus
Section B
Answer the following short question
1)
marks( 20)
What is meant by reflex arc?
2) Differentiate between resting potential and membrane potential?
3) How does the brain help us in body coordination?
4)
Why are forests important for man and his environment ?
5) Define mitosis and write its significance?
6) Differentiate between benign and malignant tumour ?
7) write down the steps of gene cloning?
8) What are molecular scissors?
9) Write the names of major ecosystems in pakistan?
10) What is the grassland ecosystem?
Section C
Question No 1 ( 8 marks)
Part a) Describe the structure of neurons with a labelled diagram?
Part b ) Explain the mechanism of Eutrophication by which type of pollution
may it occur and why ?