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#Question id: 1374


Following statements are regarding to gap junctions.

i. Vertebrate gap junctions are composed of connexins, a family of structurally related transmembrane proteins with molecular weights between 26,000 and 60,000.

ii. Each vertebrate hexagonal particle consists of six noncovalently associated connexin molecules. Each individual connexin molecule has two membrane-spanning α helices with a topology similar to that of claudin.

iii. The permeability of gap junctions is regulated by posttranslational modification of connexins (e.g., phosphorylation) and is sensitive to changes in environmental conditions

such as intracellular pH and Ca2+ concentration, membrane potential, and the intercellular potential between adjacent interconnected cells (“voltage gating”).

iv. The assembly of connexins, their trafficking within cells, and the formation of functional gap junctions apparently depend on N-cadherin and its associated adapter proteins as well as desmosomal proteins.

Which of the following statements are correct?

#Unit 4. Cell Communication and Cell Signaling
  1. i, ii and iii

  2. i and iv

  3. i, iii and iv

  4. ii and iv

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#Question id: 5736

#Unit 8. Inheritance Biology

Two zygote in which one A is 44+XYY and another B is 44+XXX karyotype is best described by

TLS Online TPP Program

#Question id: 5726

#Unit 8. Inheritance Biology

Following diagram represents the sequence of genes in a normal chromosome of a plant species

CORRECT combination for chromosomal mutation using

TLS Online TPP Program

#Question id: 5723

#Unit 8. Inheritance Biology

An individual heterozygous for a reciprocal translocation possesses the following chromosomes

I-  nonviability                                  II – Viability        

III- only translocated chromosome     IV- only normal chromosome

V- one translocated another normal

Which of the following above chromosome constituent and feature in their gamete result from?

A- alternate       B- adjacent-1     C- adjacent-2

TLS Online TPP Program

#Question id: 23966

#Unit 8. Inheritance Biology

Deletion in short arm of chromosome number 4, that leads to cause syndrome;

TLS Online TPP Program

#Question id: 5734

#Unit 8. Inheritance Biology

Following is heterozygote for inversion?

Following some statement given for above abnormality?

A) There is a less probability of a crossover occurring within inversion region and producing an enviable cross over meiotic product.

B) Chromosomes that have engaged in crossing-over separate in the normal fashion, without the creation of a bridge

C) The crossover produces chromatids that contain duplication and a deletion for different parts of the chromosome results non viable gamete

D) Double cross over within inversion loop will be results all viable gamete of parental and recombinant

TLS Online TPP Program

#Question id: 5733

#Unit 8. Inheritance Biology

In individuals heterozygous for a chromosome inversion, the homologous chromosomes form a loop in prophase I of meiosis.

Which of the following is effect of inversion?

A. A dicentric and an acentric chromosome in meiosis I as the chiasmata gets terminated when inversion includes centromere  

B. Appearance of deletion and duplication in both the cross over products chromosomes when centromere outside of inversion region  

C. All recombinant gamete are non-viable gametes when single crossing over within inverted region; irrespective to paracentric or pericentic inversion

D. Nonviable gametes are usually produced, resulting in a depression in observed recombination frequencies.

Which of the above statements are correct?