India 2011 — Theory_Paper-INBO2011.pdf

Fonte: gare di altri paesi/India/biologia/Theory_Paper-INBO2011.pdf · Apri PDF · apri PDF p.1 Cluster: Onde e Oscillazioni Soluzioni (stessa cartella): · · · · · · · · · · ·

Problema 1

CELL BIOLOGY (7)

1 INDIAN NATIONAL BIOLOGY OLYMPIAD – 2011 SECTION A

CELL BIOLOGY (7)

1. (1 point) In an experiment, the PO4 groups of the phospholipids facing the lumen of the endoplasmic reticulum (ER) are labeled. If in the course of time, the ER buds off vesicles which fuse with the cell membrane, the label will be found: a. on the PO4 groups of cell membrane facing extra cellular fluid. b. on the PO4 groups of cell membrane facing cytosol. c. only on inner lumen of ER. d. on both inner and outer laminae of ER.

2. (1 point) Which of the following primarily contribute to the ‘cytomembrane system’ of a cell? I. Endoplasmic reticulum II. Vesicles III. Microtubules IV. Mitochondria V. Golgi apparatus a. I and V only b. I, II, IV and V c. I, II and V d. I, II, III, IV and V

3. (1 point) If a very promising non-toxic drug against intestinal parasites is nonpolar in nature, then the most effective way to administer it would be: a. to give the drug in injectible form. b. to carry out liposome-mediated drug delivery. c. to give a high dosage pill.

2 d. to use minimum concentration as it can effectively pass through the lipid bilayer.

4. (1 point) The target theory suggests that the X –ray interacts directly with the genetic material and induces DNA breaks. As per this theory, the maximum damages are expected when the cells are irradiated at: a. G1 b. S c. G2 d. M

5. (1 point) The following graph was obtained when bacterial cells were added to nutrient medium and then observed for next 50 hrs.

If curves P and Q respectively indicate the total cell population and living cell population, then choose the curve that will correctly represent dying cell population: 10 20 30 40 50 hrs 1000

600

200 0 No. of cells (x102) P Q 10 20 30 40 50 hrs 1000

600

200 0 No. of cells 10 20 30 40 50 hrs 1000

600

200 0 No. of cells a. b.

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6. (1 point) A plant pigment could be effectively extracted when the solvent system used was non-polar and it showed the following absorption spectrum:

The pigment is most likely to be: a. chlorophyll b. carotene c. anthocyanin d. xanthophyll

absorbance 450 550 650 700 nm

1

0.5 1000

600

200 0 10 20 30 40 50 hrs No. of cells 10 20 30 40 50 hrs 1000

600

200 0 No. of cells c. d.

4 7. (1 point) A cDNA library is a population of bacterial transformants in which each mRNA isolated from an organism is represented in the cDNA form. Choose the correct sequence in an experiment of production of cDNA: A. Processed mRNA B. Treatment with RNAase C. Addition of poly T primers D. Addition of DNA polymerase I E. Treatment with DNAase F. Addition of Reverse transcriptase G. DNA Template H. DNA-RNA complex

a. A ÆC Æ F Æ B Æ D b. G Æ B Æ D Æ C Æ F c. H Æ B Æ C Æ F Æ A d. A Æ E Æ B Æ C Æ F

PLANT SCIENCES (9) 8. (1 point) In an experiment to generate plantlets through plant tissue culture, explants were taken from the following regions of Tectona grandis (teak) and grown on nutrient media. From which of the regions could plantlets be obtained?

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1. Leaf
2. Secondary Xylem
3. Apical bud
4. Cork
5. Axillary bud

a. Only 1, 3 and 5 b. All five c. 1, 3, 4 and 5 d. Only 1

9. (1 point) Plant cell A has an osmotic pressure of 12 atm and is immersed in solution of 10 atm osmotic pressure. Another cell B has 10 atm osmotic pressure and is immersed in solution of osmotic pressure of 8 atm. Both the cells are allowed to come to equilibrium, then removed from their solution and brought in intimate contact. Assuming that there is no external influencing force, what will be the result? a. There will be a net flow of water from A to B. b. There will be net flow of water from B to A. c. There will be no net flow of water. d. Water will freely pass from A to B but not from B to A.

10. (1 point) When effect of CO2 concentration and light intensity on rate of photosynthesis is studied the following graph is obtained.

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The limiting factors for photosynthesis in the regions A, B and C on the curves respectively are: a. A: CO2 B: light C: CO2 b. A: CO2 B: light C: light c. A: light B: CO2 C: CO2 d. A: CO2 B: CO2 C: light

11. (1 point) Carnivorous plants are found in soils that are poor in nitrogen and phosphorous and show varied adaptations to catch insects. Different plants invest differentially into development of specialized structures for carnivory. However, in doing so, they compromise on their photosynthetic ability. When the productivity of these plants was studied, following graph was obtained. High light flux Low light flux CO2 concentration Rate of Photosynthesis A B C

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The graphs I, II and III respectively indicate:

a. net photosynthesis, gross photosynthesis and respiration. b. respiration, gross photosynthesis and net photosynthesis. c. respiration, net photosynthesis and gross photosynthesis. d. net photosynthesis, gross photosynthesis and carnivory.

12. (1 point) A cell is fully turgid when: (i) $\text{Psiw}$ = 0 (ii) $\text{Psip}$ = 0 (iii) $\text{Psip}$ = $\text{Psis}$ (iv) $\text{Psiw}$ = $\text{Psis}$ a. Only (i) is correct b. Only (ii) is correct c. Both (i) and (iii) are correct d. Both (ii) and (iii) are correct

0 CO2 uptake Extent of carnivory I II III

8 13. (1 point) The concentrations of solutes present in solution A, B, C and D are given below: Solution A: 0.1 moles.L-1 sucrose + 0.1 moles.L-1 KCl

Solution B: 0.2 moles.L-1 sucrose + 0.2 moles.L-1 KCl

Solution C: 0.1 moles.L-1 sucrose + 0.1 moles.L-1 CaCl2 Solution D: 0.1 moles.L-1 sucrose + 0.2 moles.L-1 CaCl2

The decreasing order of osmolarity of the four solutions would be: a. solution A > solution C > solution D > solution B b. solution B > solution D > solution C > solution A c. solution C > solution A > solution D > solution B d. solution D > solution B > solution C > solution A

14. (1 point) The critical day lengths for 4 plants are as follows: Plant A – 15.5 hrs. Plant B – 15.5 hrs. Plant C – 10.0 hrs. Plant D – 9.5 hrs. Plant A flowers when it receives 8.5 or more hours of darkness. Plant B flowers when it receives a minimum of 15.5 hrs of light. Plant C flowers when it receives less than 10 hrs of light. Plant D flowers when it receives less than 9.5 hrs of light. Which one is a long day plant? a. Plant A b. Plant A and C c. Plant D d. Plant B

15. (1 point) Which of the following sequences explains the different steps followed by the common bread mold Mucor in obtaining nutrition?

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1. Synthesis of hydrolytic enzymes $\to$ movement of enzyme from cell into substrate $\to$ digestion of substrate by enzyme $\to$ absorption of products by cell.

2. Absorption of substrate molecules by cell $\to$ synthesis of hydrolytic enzymes $\to$ digestion of substrate by enzymes

3. Synthesis of hydrolytic enzymes $\to$ absorption of substrate molecules into cell $\to$ digestion of substrate by enzymes.

4. Synthesis of hydrolytic enzymes $\to$ absorption of substrate molecules into cell in small vesicles $\text{tomovement}$ of enzymes into vesicles $\to$ digestion of substrate by enzymes a. 1 b. 2 c. 4 d. Both 2 and 3

5. (1 point) “Serpentine soil ” is a soil that has relatively large amount of Mg++ and low levels of Ca++. Vegetation generally grows sparsely in such a soil. A plant ‘P’ could grow in such a soil but ‘Q’ could not. When the soil was supplemented with ‘Ca++’ , the results obtained can be seen in the graph. The most appropriate interpretation is:

Q P Ca++supplement introduced Dry weight

10 a. P is Ca++ tolerant plant while Q is Mg++ intolerant plant. b. P is adapted to low Ca++ condition while Q is adapted to low Mg++ condition. c. P is adapted to serpentine soil while Q is intolerant

Topic: Oscillations & Waves, Special Relativity, Fluid Mechanics Metodi: Simple Harmonic Motion Analysis, Wave Equation, Superposition Principle, Lorentz Transformation Competenze: Mathematical Modeling Fonte: Testo (PDF) — p.1