Answer the following questions
Question1)a) What will be the sequence of separation of the organelles, ribosomes, nucleus and mitochondria in a tissue homogenate when subjected to centrifugation. Explain your answer.
b) How are peroxisomes and lysosomes generated in a cell?
c) Briefly describe different modes through which cell membrane controls the transport of ingoing and outgoing molecules?
Question2)a) What are reducing sugars? Sucrose is made up of two reducing sugars however it does not show the property of a reducing sugar. Explain.
b) A fat has low iodine number and a high saponification number. What do you inferform that? What are essential fatty acids and why are they essential?
Question3)a) Draw the structure of a dinucleotide of adenosine – 5’- phosphate and uridine- 5’-phosphate.
b) In which process of protein biosynthesis, t-RNA is involved? Illustrate the gross structural features of t-RNA. Indicate the different regions.
c) Write a brief note on the various forms of DNA.
Question4)a) Briefly explain the four ways by which enzymes can lower the activation energy.
b) What is optimal pH? How can a change in pH render an enzyme inactive?
Question5)a) Name the vitamin whose coenzyme is unknown. What is the significance of this enzyme in our diet?
b) Why is calcitriol classified as a hormone?
c) What is the difference between macrominerals and trace elements? Write the major functions of any four trace elements?
Question6)a) How is the standard free energy for chemical reactions different form the standard free energy for biochemical reactions?
b) Determine the value of free energy for a reaction when Keq is 1.0 and for another reaction where Keq is 10.
c) With the help of the example describe the importance of coupling in biological reactions.
Question7a) Standard free energy change alone could not predict the direction of a biochemical reaction. Comment.
b) Enlist all enzymes involved in glycolysis and write type of reaction they catalyse.
Question8)a) What is meant by respiratory control? How is the rate of flow of electrons through the electron transport chain regulated?
b) Why are chlorophyll molecules coloured? What are the other types of light absorbing substances in plants and how they are important?
Question9)a) Compare function of RNA polymerase with DNA polymerase. How is transcription terminated?
b) What are the components of initiation complex during protein biosynthesis in E.coli? How does the elongation of chain take place?
Question10a) Explain genetic engineering? Discuss its importance to mankind.
b) Name various types of antibodies. What are the gross structural features of an antibody molecule? Discuss any one mechanism by which antibodies interact with antigens.