ASSESSMENT II
CLASS XI BIOLOGY
MAX. MARKS: 30 TIME: 1 HR
NAME____________ CLASS_____SECTION__________ ROLL NO.
This paper comprises of two Parts- I and II. Answer all Questions
Ensure that you focus on key words/phrases so as to complete in the
stipulated time
PART I (20 Marks)
Q.1 a) State the best known contributions of the following: [2X1]
i) Knoll and Ruska ii) J. D. Robertson
b) Give reasons for the following: [2x2]
i) Tryptophan is an essential amino acid.
ii) Variations in genetic characters is only possible in meiotic cell division.
Q.2 ‘Enzymes are biological catalysts.’ Comment. [4]
Q.3 i) Give diagrammatic representation of metaphase in both mitosis as
well as meiosis (metaphase I), where chromosome number is 2n=4. [5]
ii) Give diagrammatic representation of fluid-mosaic model of
plasma membrane. [5]
PART II (10 Marks)
Q.4 Give an account of the levels of protein structure.
List the functions of proteins. [5]
OR
Give the significant roles played by mitosis as well as meiosis (separately).
Q.5 Describe DNA Model as proposed by Watson and Crick. [5]
OR