Chapter 9, Problem 16SA

Summary Introduction

a.

To determine:

The term that describes “protein-coding segment”.

Answer to Problem 16SA

Correct answer:

Protein-coding segment: Exon.

Explanation of Solution

$\text{mRNA}$ is composed of two regions, one is the intron and the other is the exon. The non-coding part of $\text{mRNA}$ is called intron. However, the coding part is known as an exon. It has been observed that introns interfere during the process of translation. Exons have the ability to code for amino acids. These amino codes join together by peptide bonds to form proteins. Therefore, the protein-coding segment of $\text{mRNA}$ is called exon.

Summary Introduction

b.

To determine:

The term that describes “transcription begins here”.

Answer to Problem 16SA

Correct answer:

Transcription begins here: Promoter.

Explanation of Solution

$\text{RNA}$ polymerase is the enzyme that plays an important role in transcription. It attaches to $\text{DNA}$ by the help of a binding site. This binding site is known as the promoter. The promoter site is a particular sequence of DNA which is complementary to $\text{RNA}$ polymerase. As a result, the $\text{RNA}$ polymerase binds to promoter site of $\text{DNA}$ and starts the transcription process. Therefore, promoter is the region at which transcription starts.

Summary Introduction

c.

To determine:

The term that describes “read as base triplets”.

Answer to Problem 16SA

Correct answer:

Read as base triplets: Genetic message.

Explanation of Solution

$\text{mRNA}$ stands for “messenger $\text{RNA}$”. It is a type of $\text{RNA}$ molecule. The major function of $\text{mRNA}$ is to carry a translatable message. It also contains the genetic messages. The $\text{mRNA}$ consists of many bases. A collection of three bases that has the capability to code for a particular amino acid is called codon. Codons are present in the $\text{mRNA}$. The $\text{mRNA}$ reads genetic messages as base triplets.

Summary Introduction

d.

To determine:

The term that describes “removed before translation”.

Answer to Problem 16SA

Correct answer:

Removed before translation: Intron.

Explanation of Solution

$\text{mRNA}$ is composed of two regions, one is the intron and the other is the exon. The non-coding part of $\text{mRNA}$ is called intron. However, the coding part is known as an exon. It has been observed that introns interfere during the process of translation. As a result, the transcribed $\text{mRNA}$ undergo some modification changes. In these changes, the intron region is removed from the

Summary Introduction

e.

To determine:

The term that describes “occurs only in groups”.

Answer to Problem 16SA

Correct answer:

Occurs only in groups: Polysome.

Explanation of Solution

The ribosome is the cell organelle that has the capability to synthesize proteins. The process of conversion of $\text{mRNA}$ into proteins is termed as translation. Ribosome plays an important role in translation process. The collection of ribosome is termed as polysome. This type of collection increases the synthesis of proteins. Polysomes always occur in groups.

Summary Introduction

f.

To determine:

The term that describes “64 codons”.

Answer to Problem 16SA

Correct answer:

64 codons: Genetic code.

Explanation of Solution

A collection of three bases that has the capability to code for a particular amino acid is called codon. Codons are present in the $\text{mRNA}$. There are 64 codons present in the $\text{mRNA}$. Genetic code is formed by the combination of all the codons present in $\text{mRNA}$. However, the environment contains only twenty amino acids. Three bases form one amino acid. Therefore, genetic code is the collection of 64 codons.

Summary Introduction

g.

To determine:

The term that describes “destroy ribosomes”.

Answer to Problem 16SA

Correct answer:

Destroy ribosomes: $\text{RIP}$.

Explanation of Solution

$\text{RIP}$ stands for “ Ribosome-inactivating protein”. These are the protein molecules that have the capability to destroy the ribosome. This creates interference in the translation process. Ribosomes are the organelles that show active participation in protein synthesis. They help in translation. However, $\text{RIP}$ destroys the ribosomes and stops translation process.

Summary Introduction

h.

To determine:

The term that describes “often causes a frameshift”.

Answer to Problem 16SA

Correct answer:

Often causes a frameshift: Deletion.

Explanation of Solution

Mutation is defined as the changes in the genetic material of an organism. There are different types of mutation, such as frameshift mutation and so on. Generally, mutation occurs either due to insertion or deletion in the genetic material. Frameshift is caused due to the deletion of a nucleotide from the genetic material. This interferes with the normal functioning of the cell.

Summary Introduction

i.

To determine:

The term that describes “enzymatic $\text{RNA}$”.

Answer to Problem 16SA

Correct answer:

Enzymatic $\text{RNA}$: $\text{rRNA}$.

Explanation of Solution

Every organism present in nature contains genetic material. There are two types of genetic material. These are $\text{DNA}$ and $\text{RNA}$. $\text{DNA}$ stands for “Deoxyribonucleic acid” and $\text{RNA}$ represents “Ribonucleic acid”. $\text{RNA}$ is of three types, “$\text{mRNA}$, $\text{tRNA}$ and $\text{rRNA}$”. Ribosome contains $\text{rRNA}$ . $\text{rRNA}$ acts as a catalyst. It helps in the formation of peptide bonds between amino acids to form proteins. The $\text{tRNA}$ is not a protein molecule. It is an enzyme that increases the protein synthesis by providing suitable conditions for translation.

Summary Introduction

j.

To determine:

The term that describes “binds to codon

Answer to Problem 16SA

Correct answer:

Binds to codon: Anticodon.

Explanation of Solution

The $\text{mRNA}$ consists of many bases. A collection of three bases that has the capability to code for a particular amino acid is called codon. Codons are present in the $\text{mRNA}$. These codons attach with the anticodon part of $\text{tRNA}$ to synthesize amino acid. The anticodon part of $\text{tRNA}$ is complementary to the codon part of $\text{mRNA}$. As a result, codon and anticodons join together and undergo a translation process to produce proteins.