Question

1. The process of splicing:

Group of answer choices

a. Removes intron sequences

b. Removes polypeptides

c. Joins exon sequences

d. a) and c)

e. b) and c)

2.

Which of the following functions is not attributed to non-coding RNA?

Group of answer choices

a. RNA interference

b. Degredation of mRNA

c. Splicing of RNA

d. Post-translational modification of proteins

e. All of the above are the functions of non-coding RNA

3.

Conversion between electrical / chemical signals

Group of answer choices

a. Conversion between electrical / chemical signals

b. Reception of signal

c. Signal transmission

d. Pre- and Post-synaptic changes

e. All of the above

Answer 1

Ans 1) d, is the correct option( removes intron sequences and joins exon sequences )

Correct Explanation:-The process of splicing removes intron sequences and joins exon sequences. The pre-mRNA formed after transcription has both coding ( exons) as well as non- coding (introns) sequences. The pre- mRNA undergoes splicing, a process which removes the non- coding (introns) and joins the coding exon sequences and form mRNA which will undergo translation to form proteins.

Ans 2) e, is the correct option (All of the above)

These are the functions of non- coding RNA.Non- coding RNA is functional RNA which is transcribed from DNA but it does not undergo translation into a protein. There are many types of ncRNA like miRNA, siRNA, tRNA, rRNA etc. ncRNA form components of spliceosome which performs splicing of RNA. miRNA, siRNA takes part in RNA interference,thus silencing the mRNA. miRNA can also cause mRNA degradation or cleavage by binding to it. nc RNA also take part in post translational modification of proteins.Long non coding RNA(lncRNA) interact with proteins at post translational levels.

Ans 3 ) d , is the correct option Pre- and post- synaptic changes invoke conversion of electrical signal into chemical signals. A nerve impulse travel in a nerve cell as an electrical signal called action potential. When it reaches the synapse, it changes into chemical signal in the form of neurotransmitters which cross the synapse and bind the receptors on the othe nerve cell.