India 2010 — inbo2010-Q.pdf

Fonte: gare di altri paesi/India/biologia/inbo2010-Q.pdf · Apri PDF · apri PDF p.1 Cluster: Meccanica Soluzioni (stessa cartella): · · · · · · · · · · ·

Problema 1

CELL BIOLOGY (6)

1 INDIAN NATIONAL BIOLOGY OLYMPIAD – 2010 SECTION A

CELL BIOLOGY (6)

1. (1 point) Mammals contain white adipose tissue (WAT) and brown adipose tissue (BAT). WAT is the primary source of lipid used to produce energy in the form of ATP whereas BAT is the primary source of thermogenesis under cold stress. Which of the following features of the mitochondrial inner membrane of BAT contribute to this effect? a. Increased permeability for protons. b. Less of ATP synthase embedded in the membrane. c. Absence of electron transport chain. d. Presence of inhibitors of electron transport chain.

2. (1 point) Among carbohydrates, lipids, proteins and ATP, the relative energy yield in kcal per gram is best represented by: a. lipids > carbohydrates > ATP b. ATP > lipids > proteins c. lipids > ATP > carbohydrates d. lipids > proteins > ATP

3. (1 point) Following is the picture of a microsatellite gel of two loci from a chick, its mother and 6 males from a population. Can the biological father of the chick be ascertained from the data?

M 2 C Mo M 1 M 3 M 4 M 5 M 6 1 2 2 1 Locus 2 Locus 1 C: Chick Mo:Mother M: Male

2 a. Yes, the biological father is male 5. b. Yes, the biological father is male 1. c. Yes, the biological father could either males 2 or 3. d. No, at least three loci need to be shown for the decision.

4. (1 point) Consider the glycolytic pathway.

In a hibernating animal, the enzymes that will be up- and down-regulated will respectively be: a. (3) and (2) b. (1, 2, 4) and (3) c. (1, 2) and (3, 4) d. (2) and (1) Glyceraldehyde- 3 – phosphate dehydrogenase 1 Pyruvate dehydrogenase kinase Pyruvate dehydrogenase phosphatase Inactive Pyruvate dehydrogenase 3 Pyruvate Acetyl CoA Active Pyruvate dehydrogenase 2 Glucose Triose phosphate 1,3 bis-phosphoglycerate 4

3 5. (1 point) Graph (A) represents a typical histogram of normally dividing cells in a cell cycle analysis study. The graph (B) represents the histogram of cells treated for 24 h with a protein ‘x’ of unknown function.

The protein ‘x’ here acts as a: a. GO G1 phase inhibitor. b. G2 M phase inhibitor. c. Apoptosis inducer. d. G1 S phase inhibitor.

6. (1 point) Analysis of a protein sequence from a recently mutated gene showed that the newly expressed protein had a completely different sequence from the wild-type protein. This was due to a: a. missense mutation. b. nonsense mutation. c. silent mutation. d. frameshift mutation. Relative DNA content Relative DNA content Relative DNA content Relative DNA content

4 PLANT SCIENCES (8)

7. (1 point) The factors that enhance the transition of apical bud into floral bud are:

8. low light conditions.

9. attaining threshold apical bud size.

10. reduction in the availability of carbohydrates to the apex.

11. exogenous application of gibberellins. a. only 1 and 3 b. only 2 and 4 c. only 1,3 and 4 d. 1,2,3 and 4

12. (1 point) Guttation is common among the plants of this climate: a. hot and wet. b. hot and windy. c. cold and humid. d. cold and windy.

13. (1 point) Turgor pressure is required to maintain the shape of all cells except: a. meristematic cells. b. root cells. c. collenchyma cells. d. lignified cells.

14. (1 point) Bacteriorhodopsin absorbs a quantum of light by P570 which is transformed into P412 accompanied by release of H+. It is also known that F0-F1 system generates ATP through the movement of H+. What should be the appropriate diagram for a photosynthetic Halobacterium halobium?

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11. (1 point) Mark the odd pair out. a. Totipotency: parenchyma b. Secondary growth: cambium c. Dermal cells: trichomes d. Periderm: collenchyma

12. (1 point) The limiting factor/s for photosynthesis in regions A and B in the graph is/are:

Low light intensity Moderate light intensity B A 0.05

0.2 0.25 CO2 conc. (% by vol) CO2 fixed Indicates pigment. c. d. $h\upsilon$ ATP ADP+Pi H+ P570 P412 H+ H+ $h\upsilon$ ATP ADP+Pi H+ P570 P412 H+ H+ H+ $h\upsilon$ ATP ADP+Pi H+ P570 P412 H+ H+ $h\upsilon$ ATP ADP+Pi H+ P570 P412 H+ a. b.

6 a. A: light intensity B: CO2 concentration b. A: light intensity B: Light intensity c. A: CO2 concentration B: Light intensity d. A: CO2 concentration B: CO2 concentration

13. (1 point) If a plant is grown only in sand (S), only in clay (C) or only in humus (H), which of the following will be true? i. Water availability to the roots will be more in (C) and (H) as compared to (S). ii. Nutrient availability will be more in (C) and (H) as compared to (S). iii. Oxygen availability will be low in (C) as compared to (S) and (H). iv. The ability of roots to penetrate (S) and (H) will be low as compared to (C). a. i only b. both ii and iii c. both i and iv d. i, ii and iii

14. (1 point) In order to study the effect of water availability on plant growth, broadleaf peppermint seedlings were grown under two conditions (I and II) in a greenhouse and the supply of water to the plants was varied. Condition I: one seedling potted per pot Condition II: 16 seedlings potted per pot When the root to shoot biomass was calculated, the following graph was obtained.

Root weight/shoot weight 16 plants /pot

1 plant /pot 100 200 300 Water (ml/day)

7 Mark the correct interpretation. a. Water availability and competition both increase the root to shoot weight ratio in plants. b. Shortage of water leads to increase in root to shoot weight ratio. This effect is enhanced when there is competition. c. Water availability increases root to shoot weight ratio. This effect can be countered by competition. d. Competition leads to decrease in root biomass while scarce supply of water tends to counterbalance this effect.

ANIMAL SCIENCES (6)

15. (1 point) The data below was obtained from an experiment when a golden mantled squirrel was kept in the laboratory for 2 years under constant light and dark condition (12 hrs. light and 12 hrs. dark) and temperature $(22^{\circ }C$).

Body Mass per kg Food consumption (gm/day) M J J A S O N D J F M A M J J A S O N D J F M A 0.35 0.1 Months Body Mass per kg Food consumption (gm/day)

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The graph indicates that the animal is: a. an obligate hibernator with exogenous signals for entry into hibernation. b. a facultative hibernator with endogenous signals for entry into hibernation. c. an obligate hibernator with endogenous signals for entry into hibernation. d. a facultative hibernator with exogenous signals for entry into hibernation.

16. (1 point) In vertebrates the long bones are always hollow. The advantages that this anatomy provides are that:

17. they harbour and protect marrow.

18. they provide attachment to tendons.

19. they are stronger than solid structures made of same amount of material.

20. only hollow bones can articulate better with one another. a. Only 1, 2 and 4 b. Only 1 and 3 c. Only 1, 3 and 4 d. 1, 2, 3 and 4

21. (1 point) Collagenase is an enzyme that breaks the peptide bonds in collagen. Excessive secretion of this enzyme will lead to weakening of:

22. bones

23. tendons

24. intervertebral discs

25. hair shafts

26. nails & claws a. 1, 4, & 5 b. 2, 3 & 5 c. 1, 2, & 4 d. 1, 2, & 3

9 18. (1 point) Predominant chitinase activity will be detected in the gastric mucosa and pancreas of: a. sheep. b. rabbit c. pigeon d. salamander

19. (1 point) The percentage of digesta fluids and particulate markers recovered from the gastrointestinal tract of two animals is shown in the figures below. (S= stomach, SI=Small intestine, Ce= Cecum, C= colon, Fe= Feces)

P and Q respectively are: a. herbivore and carnivore. b. omnivore and herbivore. c. foregut fermentor and hindgut ferm

Topic: Thermodynamics, Kinetic Theory Metodi: Physical Modeling, Experimental Data Analysis Competenze: Physical Reasoning, Experimental Data Analysis Fonte: Testo (PDF) — p.1