Tag: inherited changes

Quizzes (4) Questions (88)

Questions Related to inherited changes

Multiple choice expression of gene inherited changes biology

Eucaryotic genome differs from procaryotic genome in

  1. DNA is circular arid single-stranded in procaryotes

  2. Intervening sequences are present in eucaryotic DNA

  3. DNA is coinplexed with histones in procaryotes

  4. DNA is organised into operons in eucaryotes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Eukaryotic genes are characterized by split gene organization, meaning they contain non-coding intervening sequences called introns that are removed during RNA processing. Prokaryotic genomes generally lack these introns.

Multiple choice expression of gene inherited changes biology

Operon is

  1. Sequence of three nitrogen bases determining a single amino acid

  2. A set of closely placed genes regulating a metabolic pathway in procaryotes

  3. Segment of DNA specifying a polypeptide

  4. Gene responsible for switching on and switching off of other genes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An operon is a functional unit of DNA in prokaryotes consisting of a cluster of genes under the control of a single promoter and operator, allowing for the coordinated regulation of a metabolic pathway.

Multiple choice expression of gene inherited changes biology

In eukaryotes transcription occurs in

  1. Cytoplasm

  2. Nucleus

  3. Cytosol

  4. Matrix
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In eukaryotic cells, the DNA is contained within the nucleus, which is where the process of transcription (DNA to RNA) occurs. Translation then takes place in the cytoplasm.

Multiple choice expression of gene inherited changes biology

In an inducible operon, the genes are

  1. Usually expressed unless a signal turns them "off

  2. Never expressed

  3. Always expressed

  4. Usually not expressed unless a signal turns them on
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Inducible operons are typically in an 'off' state due to the presence of a repressor protein bound to the operator. They are turned 'on' only when an inducer molecule binds to the repressor, preventing it from binding to the DNA.

Multiple choice expression of gene inherited changes biology

In processing of eukaryotic hnRNA during protein-synthesis tailing involvesof RNA

  1. Addition of adenylate residues at 3' end

  2. Addition of methyl guanosine triphosphate at 3' end

  3. Addition of methyl guanosine triphosphate 5' end

  4. Removal of introns
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During the processing of eukaryotic hnRNA, tailing (polyadenylation) involves the addition of a long chain of adenylate residues (poly-A tail) to the 3' end of the transcript to protect it and aid in export.

Multiple choice expression of gene inherited changes biology

In operon model, the function of regulator gene is to produce

  1. Repressor

  2. Inducer

  3. Corepressor

  4. DNA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The regulator gene in an operon system codes for a repressor protein, which is responsible for binding to the operator site to inhibit transcription of the structural genes.

Multiple choice expression of gene inherited changes biology

The enzyme peptidyl transferase of prokaryotes resides in 

  1. 50 S ribosome

  2. 30 S ribosome

  3. 40 S ribosome

  4. 60 S ribosome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In prokaryotes, the peptidyl transferase activity, which catalyzes the formation of peptide bonds during translation, is an intrinsic function of the 23S rRNA component of the 50S ribosomal subunit.

Multiple choice expression of gene inherited changes biology

Prokaryotic enzyme with 5'--> 3 exonuclease property is

  1. DNA polymerase I

  2. DNA polymerase II

  3. DNA polymerase III

  4. Both A and C
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DNA polymerase I is unique among the prokaryotic DNA polymerases because it possesses 5' to 3' exonuclease activity, which is essential for removing RNA primers during DNA replication.

Multiple choice expression of gene inherited changes biology

Which of the following DNA polymerase of prokarytoes have both 3' - 5' and 5' - 3' exonuclease activity

  1. DNA Pol-II

  2. DNA Pol-I

  3. DNA Pol-IV

  4. DNA Pol-III
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

DNA polymerase I is the only prokaryotic DNA polymerase that possesses both 3' to 5' exonuclease activity (for proofreading) and 5' to 3' exonuclease activity (for primer removal).

Multiple choice expression of gene inherited changes biology

Prokaryotes can be distinguished from eukaryotes as they lack

  1. RNA

  2. Ribosomes

  3. Gene discontinuity

  4. Unique DNA sequences
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Prokaryotes lack split genes, meaning their coding sequences are continuous and do not contain introns. Eukaryotic genes are frequently interrupted by non-coding introns.