Life Sciences - (XL) 2018 GATE Paper (Practice Test - 3) - GATE

Identify the CORRECT statement.

 Which of the following statements is TRUE for an ecotone?

Acid rain with a pH of 4.0 is more acidic than the rain with a pH of 6.0 by

 Which of the following plants produces Ylang-ylang oil?

Identify the INCORRECT statement in connection with polar transport of auxin.

 Which of the following stains is used to visualize callose under the microscope?

The coding sequence of a gene XLR18 has the single ORF of 783 bp. The approximate molecular weight of the XLR18 protein in kDa is ______

Statements given below are either TRUE (T) or FALSE (F). Select the CORRECT combination.  

P. Mitosis occurs exclusively in diploid mother cell

Q. Mitosis occurs both in diploid and haploid mother cells

R. Meiosis occurs exclusively in diploid mother cell

S. Meiosis occurs both in diploid and haploid mother cells

You are asked to design a genetic construct for high-level expression of a gene encoding the therapeutic protein 18 (TP18) via plastid transformation. Select the CORRECT set of genetic elements for this construct.    

Select the CORRECT combination of the following statements.  

P. The cyclic electron transport chain involving PSI results in net production of both ATP and NADPH

Q. The cyclic electron transport chain involving PSI results in net production of ATP

R. Rubisco enzyme usually converts RuBP and CO2 into 2-phosphoglycolate and 3-phosphoglycerate

S. Rubisco enzyme usually converts RuBP and O2 into 2-phosphoglycolate and 3-phosphoglycerate  

 Match the fruit characters with their families and representative plant species. 

Select the CORRECT combination by matching the disease, affected plant and the causal organism

  Select the CORRECT combination by matching Group-I with Group-II. 

 Match the plant alkaloids with their uses and source species. 

  Identify the CORRECT combination of statements with respect to chemical defense in plants. 

 P. Pisatin, a phytoalexin produced by Ricinus communis is a constitutive defense compound

Q. Phaseolus vulgaris produces Phaseolus agglutinin I, which is toxic to the cowpea weevil  

R. A single step non-enzymatic hydrolysis of cyanogenic glycoside releases the toxic hydrocyanic acid (HCN) to protect plant against herbivores and pathogens

S. Avenacin, a triterpenoid saponin from oat prevents infection by Gaeumannomyces graminis, a major pathogen of cereal roots  

  In garden pea, dwarf plants with terminal flowers are recessive to tall plants with axial flowers.  A true-breeding tall plant with axial flowers was crossed with a true-breeding dwarf plant with terminal flowers. The resulting F₁ plants were testcrossed, and the following progeny were obtained:  
Tall plants with axial flowers = 320  
Dwarf plants with terminal flowers = 318
Tall plants with terminal flowers = 79
Dwarf plants with axial flowers = 83  
The map distance between the genes for plant height and flower position is______cM. 

Two true-breeding snapdragon (Antirrhinum majus) plants, one with red flowers and another with white flowers were crossed. The F₁ plants were all with pink flowers. When the F₁ plants were selfed, they produced three kinds of F₂ plants with red, pink and white flowers in a 1:2:1 ratio. The probability that out of the five plants picked up randomly, two would be with pink flowers, two with white flowers and one with red flowers is _____%