Carbohydrates synthesizes by photosynthesis are converted into sucrose and transported via phloem to other parts of the plant. The following aspects are associated with sucrose uploading in phloem and its transport:

A. Both reducing and non-reducing sugars are transported efficiently through phloem.

B. Sucrose uploading can be both symplastic and apoplastic.

C. The route of phloem uploading is mesophyll cells → phloem parenchyma → companion cells → sieve tubes.

D. Transport in sieve tubes is as per the 'pressure-flow model'.?

Which one of the following combinations is correct

• A, B and C

• B, C and D

• C, D and A

• D, B and A

Symbiotic nitrogen fixation in legume nodules involves complex interaction between Rhizobium and legume roots. This complex interaction is governed by

A. Integration of sym plasmid of Rhizobium in the root nuclear genome.

B. Sensing of plant flavonoids by rhizobia.

C. Activation of nod genes in rhizobia.

D. Activation of NODULIN genes in legume roots.

Which one of thefollowign combinations is correct?

• A, B and C

• A, C and D

• B, C and D

• A, B and D

103.

A 'Z' scheme describes electron transport in O₂-evolving photosynthetic organisms. The direction of electron flow is presented in the following sequences:

A. P680* → Pheophytin → Q_A → Q_B → PC → cytochrome b₆f → P700

B. P700* → Phylloquinone-FeS_A → FeS_B → FeS_x → Fd

C. P680* → Pheophytin → Q_A → Q_B → cytochrome b₆f → PC → P700

D. P700* → Phylloquinone → FeS_X → FeS_A → FeS_B → Fd

Which one of the following combinations is correct?

• A and B

• B and C

• C and D

• D and A

Following are certain statements related to plants exposed to dehydration stress:

A. When the water potential of the rhizosphere decreases due to water deficit, plants can continue to absorb water as long as plant water potential is lower than that of soil water.

B. The ratio of root to shoot growth increases in response to water deficit.

C. Plant cells tend to release solutes to lower water potential during periods of osmotic stress.

D. Abscisic acid is synthesized at a higher rate when leaves are dehydrated, and more ABA accumulates in the leaf apoplast.

Which one of the following combinations of above statements is correct?

• A, B and C

• B, C and D

• A, B and D

• A, C and D

A cross was made between Hfr met⁺ arg⁺ leu⁺ str^S X F^- met^- arg^- leu^- str^R, in which leu⁺ exconjugates are selected. If the linear organization of the genes are leu⁺ arg⁺ met⁺, which one of the following genotypes is expected to occur in the lowest frequency?

• leu⁺ arg^- met^-

• leu⁺ arg⁺ met^-

• leu⁺ arg⁺ met⁺

• leu⁺ arg^- met⁺

Two homozygous individuals (P1 and P2) were genotyped using dominant DNA markers A and B, as shown below. The F₁ progeny obtained was test crossed. The frequency of progeny with which different genotypes appear, is given below:

The following conclusions were made:

A. In the F₁, markers A and B are linked and in coupling phase (cis).

B. In the F₁, markers A and B are linked and in repulsion phase (trans).

C. The distance between A and B is 10 cM.

D. The distance between A and B is 5 cM.

Which of the above conclusions are correct?

• A and C

• A and D

• B and C

• B and D

The above pedigree sows the inheritance of a rare allele. The allele is 

• X-linked recessive

• Autosomal recessive

• Dominant with incomplete penetrance

• Autosomal recessive with incomplete penetrance

A plant with red fruit is crossed to a plant with white fruit. The F₁ progeny had red fruits. On selfing the F₁, the two kinds of progeny were observed, plants with red-fruits and those with white-fruits. To test whether it was a case of recessive epistatic interaction a chi-square test was performed. A value of 1.062 was obtained (chi-square value at P_0.05 = 3.841 for Degree of Freedom = 1). The following statements were made:

A. The null hypothesis was that plants with red and white fruits will occur in a 9 : 7 ratio.

B. The null hypothesis was that plants with red and white fruits will occur in a 1 : 1 ratio.

C. Based on the chi-square value, it is a case of recessive epistatic interaction.

D. Based on the chi-square value, it is not a case of recessive epistatic interaction.

Which of the combination of above statements is correct?

• A and C

• A and D

• B and C

• B and D

Somatic recombination was caused by mild exposure to radiation on flies heterozygous for a given allele during specific stages of development and the individuals were allowed to develop. Such individuals are likely to have 

A. clones of homozygous cells in heterozygous body.

B. site specific mutagenesis.

C. twin spots, i.e. patches of mutants cells and homozygous wild type cells in heterozygous body.

D. tissue specific expression of the given allele.

Which of the following combination of answers will be most appropriate?

• A and B

• B and C

• A and c

• C and D

Sickle cell anemia is a recessive genetic disease caused due to a point mutation in the 6^th codon abolishing one of the MspII endonuclease digestion site present in the β-globin gene. MspII digested DNA from a normal person gives two bands, 1150 bp and 200 bo, in β-globin gene. A family with a proband (based on the disease phenotype) gave the following MspII digestion pattern:

The following conclusions were draw:

A. Son (I) is the proband and the given mutation is not present in Son (II).

B. The daughter is a carrier for the given mutation.

C. The gene is X-linked and thus are affected.

D. A de Novo mutation in same site on normal allele has allowed appearance of disease phenotype in the proband.

Which of the following combination of conclusions will be the most appropriate for the figure given above?

• A,B and E

• A, B and C

• B, C and E

• C and D