Practice Questions

TLS Online TPP Program

#Question id: 2897

The transcription of most protein coding genes in mammals (~70 percent) occurs at a lower rate than at TATA box–containing and initiator-containing promoters and begins at any of several alternative start sites within regions of about 100–1000 bp that have an unusually high frequency of CG sequences. Which one of the following best explains it?

#Unit 2. Cellular Organization

CG-rich sequences are bound by histone octamers more tightly than CG-poor sequences because less energy is required to bend around the histone octamer forming a nucleosome.
During housekeeping gene expression, the enzyme methyltransferase is temporarily silenced by miRNA, thus shutting down global methylation.
As soon as the cytosine is methylated in the promoter region, the enzymes of DNA repair pathways remove the methyl group, thereby ensuring gene expression.
A remarkable feature of the CpG islands is that transcription from these elements is initiated in both directions, even though only transcription of the sense strand yields an mRNA.

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TLS Online TPP Program

#Question id: 15899

#Unit 12. Applied Biology

Somatic embryos (SEs) regenerate from the tissues of other SEs or the parts of germinating SEs; such SEs are called

TLS Online TPP Program

#Question id: 15900

#Unit 12. Applied Biology

During development of a somatic embryo from a single superficial cell of the explant, the cells of this meristematic mass continue to divide to give rise to the various stages of SEs. Which of the following is considered correct for the development of SEs?

TLS Online TPP Program

#Question id: 15901

#Unit 12. Applied Biology

The following features are included between the shoot buds and somatic embryo;

A) SHOOT BUD i) Originated from the many cells, usually superficial

B) SOMATIC EMBRYO ii) Polarity is defined as bipolar; both shoot and root poles present

iii) Vascular strands connected with those present in callus/explant

iv) Easily separated from the callus/explant

v) There is no vascular connection with callus/explant

Which of the following correctly represents the features of shoot buds and somatic embryo?

TLS Online TPP Program

#Question id: 15902

#Unit 12. Applied Biology

The pair of hormones required for a callus to differentiate are____

TLS Online TPP Program

#Question id: 15903

#Unit 12. Applied Biology

Protoplast can be produced from suspension cultures, callus tissues or intact tissues by enzymatic treatment with

TLS Online TPP Program

#Question id: 15904

#Unit 12. Applied Biology

If the cell arc treated with 0.01% solution of FDA, what will be the effect on live cell?