BOT/III/EC/05 Student's Copy
2 0 1 8
CBCS
3rd Semester
BOTANY
THIRD PAPER
Plant Physiology, Biochemistry and Ecology
Full Marks 75
Time 3 hours
PART A—OBJECTIVE
Marks 25
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 10
Tick the correct answer in the brackets provided 1×10=10
1. The difference in the chemical potential of water in a solution and that of
pure state is called
osmotic pressure
water potential
imbibition
None of the above
2. Calvin and Benson studied steps of dark reaction in which green algae?
Chlamydomonas
Volvox
Chlorella
Eudorina
/53 1 Contd.
3. Halophytes are plants growing in
saline environment
alkaline environment
arid regions
None of the above
4. Which of the following pyramids is always upright?
Pyramid of number Pyramid of biomass
Pyramid of energy Pyramid of age
5. Migration and establishment of plants in new areas is called
ecesis aggregation
stabilization None of the above
6. The nomenclature of enzymes according to CEIUB (1961) have code
numbers
consisting of four digits
consisting of eight digits
consisting of three digits
consisting of five digits
7. Synthesis of ATP via Electron Transport System is called
oxidative decarboxylation
non-cyclic photophosphorylation
cyclic electron transport
oxidative phosphorylation
8. The site of synthesis of auxins in plant is
lateral meristem root tip
flower All of the above
9. DNA replication starts at a specific point is called
Okazaki fragment origin
primer site replication fork
10. The hormone produced as a result of photoperiodic induction is
cytokinin vernalin
florigen phytochrome
BOT/III/EC/05/53 2 Contd.
SECTION—B
Marks 15
Write short notes on the following 3×5=15
1. Transport of solutes
OR
Photorespiration
2. Biological nitrogen fixation
OR
Mitochondria
3. Photoperiodism
OR
Phytochrome
4. Protein synthesis
OR
Classification of carbohydrates
5. Biogeochemical cycles
OR
Community characteristics
PART B—DESCRIPTIVE
Marks 50
The figures in the margin indicate full marks for the questions
1. Define photosynthesis. Elucidate the CAM pathway of carbon fixation.
2+8=10
OR
Write accounts on any two of the following 5×2=10
Micro- and macro-nutrients
Transpiration
C4 mechanism
BOT/III/EC/05/53 3 Contd.
2. What are enzymes? Describe the mechanism of enzyme action. 2+8=10
OR
Write accounts on any two of the following 5×2=10
Structure of mitochondria
Nitrogen metabolism
TCA cycle
3. Describe seed dormancy. What are the different methods of breaking
dormancy? 2+8=10
OR
Write short notes on any two of the following 5×2=10
Physiological role of auxins
Vernalization
Senescence
4. Describe the mechanism of DNA replication. 10
OR
Write short notes on any two of the following 5×2=10
Lipids
Structure of amino acids
Translation
5. What is pollution? Write a comprehensive account on the causes and
control of water pollution. 2+8=10
OR
Write accounts on any two of the following 5×2=10
Ecological succession
Ecosystem structure
Ecological pyramids