Life Sciences- XL (GATE) 2011

There are two candidates P and Q in an election. During the campaign, 40% of the voters promised to vote for P, and rest for Q. However, on the day of election, 15% of the voters went back on their promise to vote for P and instead voted for Q. 25% of the voters went back on their promise to vote for Q and instead voted for P. Suppose, P lost by 2 votes, what was the total number of voters?

The horse has played a little known but very important role in the field of medicine. Horses were injected with toxins of diseases until their blood built up immunities. Then a serum was made from their blood. Serums to fight with diphtheria and tetanus were developed this way.
It can be inferred from the passage, that horses were

Three friends, R, S and T shared toffee from a bowl. R took 1/3^rd of the toffees, but returned four to the bowl. S took 1/4^th of what was left but returned three toffees to the bowl. T took half of the remainder but returned two back into the bowl. If the bowl had 17 toffees left, how many toffees were originally there in the bowl?

The fuel consumed by a motorcycle during a journey while traveling at various speeds is indicated in the graph below.

The distances covered during four laps of the journey are listed in the table below.

From the given data, we can conclude that the fuel consumed per kilometer was least during the lap

Two purified DNA samples A and B contain equal number of base pairs. Each of these DNA samples has one site each for EcoRI and BamHI restriction enzymes. Complete digestion with both the enzymes yielded 3 DNA bands and 2 DNA bands respectively for A and B upon electrophoresis of the digestion products. Which one of the following explains the observation?

Which of the following statements in photosynthesis are CORRECT?
P. The absorption maxima for photosystem I (PS I) and PS II are 680 nm and 700 nm, respectively.
Q. Photosynthetic reaction centre contains 300 chlorophyll molecules and the release of one molecule of oxygen requires a minimum of 8 photons.
R. The non-photochemical quenching of excitation energy is enhanced by the presence of zeaxanthin.
S. The photochemical splitting of water occurs in PS I.

Which of the following statements are TRUE on DNA delivery methods during plant transformation?
P. Single stranded nicks are made in T-DNA border repeat by the VirD1, VirD2 and VirD3 protein complex.
Q. virA gene products form the export apptratus on the membrane for the transfer of T-DNA.
R. Gold/Tungsten particles are used as microprojectiles in biolistic method.
S. Acceleration of DNA-coated microprojectiles is carried out with compressed CO₂.

Match the following plant secondary compounds with their uses and source plants.

Match the gene of interest for various aspects of crop improvement.

Match the name of the disease with the causal organism.

Identify the CORRECT statements for phylogenetic systems of classification.
P. The most popular phylogenetic systems of classification is that of George Bentham and Joseph Dalton Hooker and was published in ‘Genera Plantarum’.
Q. A true phylogenetic system of classification was proposed by Adlof Engler and was published in ‘Die Naturlichen Pflanzenfan-ijljen’.
R. The phylogenetic system of classification proposed by John Hutchinson was appeared in ‘The Families of Flowering Plants’.
S. The origin of dicot from primitive monocot was proposed by Arthur Cronquist in his book ‘Systema Naturae’.

Which of the following statements are TRUE for the plastid genomes?
P. Plastid genome is circular in nature with genome size of 120-160 kb.
Q. The plastid ribosomes are with sedimentation coefficient of 80 S.
R. The gene for the small subunit of ribulose bisphospate carboxylase (RubisCO) is located in the plastid.
S. rRNAs in the plastid genome are arranged in one transcription unit.

Identify the CORRECT statements.
P. Specialized parenchymatous cells with tannins and crystals of calcium oxalate are termed as sciereids.
Q. The sieve elements of angiosperms are surrounded by companion cells and are essential component of phloem loading.
R. The exudation of water by guttation occurs through trichomes.
S. The bulliform cells control the unrolling and hygroscopic movement of grass leaves.

Which of the following statements are INCORRECT on ecological point of view?
P. Primary succession involving xerosere is initiated in a wet habitat.
Q. Halones commonly found in electronic equipment are one of the active force destroying the protective ozone layer in the stratosphere.
R. Sympatric speciation occurs when the new species evolves in geographic isolation from the parent species.
S. ^_$\alpha$-Diversity is the diversity of species within a habitat or community.

Match the names of investigators in Group 1 with their contributions in Group 2.

A new isolate of a facultative anaerobe utilizes either oxygen or pyruvate as terminal electron acceptor. This bacterium was grown either anaerobically with glucose as sole carbon source; or aerobically with lactose as the sole carbon source. Net increase in ATP production (per mole of the carbon source) during the aerobic growth would be

An actively growing culture (20 ml) of E. coli (1 ^_$\times$ 10⁵ per ml) was mixed with a total of 100 T4 phage particles, grown further for 40 min and mixed with a few drops of chloroform. Under the conditions used, the generation time of F. coli is 30 min, the infection cycle of phage T4 is 20 min, and the burst size is 100. Assuming that each infection was a successful one, how many plaque forming units would you expect at the end of the experiment?

Match the pair of organisms in Group 1 with their characteristic interactions in Group 2

A genetic experiment was performed to map the gene (s) for eye colour in a newly-discovered moth species. Sex determination in this moth species: XY — male and XX — female. When blue-eyed males were mated to green-eyed females, all of both male and female progeny had green eyes. When these progeny were mated among themselves, about half of the males of the resulting second generation had blue eyes; however, all females were green-eyed. Which one of the following is consistent with the above data?

In a newly discovered organism, normal development was unaffected when a few blastomeres were removed from 100-cell stage embryo. However, removal of five cells at the 1000-cell stage abolished the formation of kidney. Which one of the following options most accurately describes the type (s) of specification operating in the development of this organism?

Behavioral studies on animals have shown that there is relationship between mechanism of reproduction and male parental care (protecting eggs or the young ones). In aquatic invertebrates, fishes and amphibians for example, the species that practice internal fertilization rarely show male parental care while a majority of species that practice external fertilization tend to exhibit male parental care. This is likely due to

Match the following sauerkraut defects for their causative agents

A continuous dryer was used to dry 12 kg/min of a blanched vegetable containing 50% moisture (wet weight basis) to give a product containing 10% moisture. As the dryer could handle feed material with moisture content not more than 25%, a part of dried material was recycled and mixed with the fresh feed. The evaporation rate in the dryer will be