Question

83\. A given segment of the DNA molecule, which contains the molecular coding for a specific protein to be synthesized, is referred to as a _______.

Short answer

A given segment of the DNA molecule, which contains the molecular coding for a specific protein to be synthesized, is referred to as a "gene." The gene provides instructions for protein synthesis through a process called gene expression, where DNA information is transcribed into mRNA and then translated into amino acids that form the protein.

Step-by-step solution

Define the term

The term we are looking for is a "gene." A gene is a segment of DNA that contains the molecular coding for a specific protein to be synthesized.

Role of a gene in protein synthesis

Genes play a crucial role in protein synthesis. They provide instructions to the cell to create specific proteins. The process of decoding this information present in the gene to create the protein is known as "gene expression." During gene expression, the DNA information is transcribed into a molecule called mRNA (messenger RNA), which is then translated into the amino acid sequence that forms the protein.

Key concepts

DNA

DNA, which stands for Deoxyribonucleic Acid, is the blueprint of life found in every cell of our body. It consists of two long strands that form a double helix structure. These strands are made up of nucleotides, which are the basic building blocks of DNA. Each nucleotide contains a sugar molecule, a phosphate group, and a nitrogenous base. The sequence of these bases (adenine, thymine, cytosine, and guanine) encodes genetic information.

DNA is responsible for storing all the necessary information required for the development, functioning, and reproduction of living organisms. It's like a manual that guides how cells function, replicate, and pass on genetic information to the offspring. Within this vast genetic database, specific segments called genes hold the instructions for making proteins, which are crucial for various biological functions.

Protein Synthesis

Protein synthesis is the process by which cells produce proteins, vital components that perform a wide array of functions within organisms. This process consists of two main stages: transcription and translation.

During transcription, the DNA sequence of a gene is copied into mRNA, a process that takes place in the cell nucleus. This mRNA carries the genetic information from DNA to the cytoplasm, where the second stage, translation, occurs.

Translation is the process by which the mRNA sequence is used to build a chain of amino acids, creating a protein. The ribosome, a cellular machine, reads the mRNA sequence three bases at a time, each triplet (codon) specifying a particular amino acid. This sequence of amino acids folds into a specific 3D shape to perform its unique function within the cell.

Gene Expression

Gene expression is the process by which information from a gene is utilized to synthesize a functional gene product, usually a protein. This intricate process allows cells to react to their environment and differentiate during development.

It begins with transcription, where a particular segment of DNA is used as a template to generate a messenger RNA (mRNA) molecule. This mRNA then undergoes translation to form a protein. Gene expression is tightly regulated, ensuring that the correct proteins are produced at the right time and place.

• Regulation of gene expression helps an organism adapt to new conditions by altering the levels and functions of its proteins.
• Misregulation can lead to diseases such as cancer.

Understanding gene expression helps us comprehend how organisms grow and respond to their environment, making it crucial for fields like genetics and biotechnology.

mRNA

Messenger RNA, or mRNA, plays a crucial role in conveying genetic information from DNA to the cellular machinery involved in protein synthesis. Often referred to as the "messenger," mRNA is a single-stranded molecule that is synthesized during transcription.

In this process, the DNA sequence of a gene is copied into mRNA, which travels from the nucleus to the cytoplasm. Here, the ribosome reads the encoded instructions to synthesize proteins. This pathway allows the cell to translate genetic information into physical traits.

• mRNA's role as an intermediary is vital because it provides a disposable copy of a gene, preventing the DNA from being directly exposed to potential damage.
• mRNA vaccines, like those used for COVID-19, showcase the potential of this molecule in advancing medical science.

Thus, mRNA is indispensable in ensuring the accurate production of proteins and the preservation of genetic information.

Amino Acid Sequence

An amino acid sequence is the order in which amino acids are linked together to form a protein. This sequence is determined by the sequence of nucleotides in the mRNA during translation, making it a critical step in protein formation.

Amino acids, the building blocks of proteins, are joined by peptide bonds, creating a polypeptide chain that folds into a three-dimensional structure specific to its function.

• The specific sequence determines the protein's unique properties and function within the organism.
• Changes or mutations in the sequence, known as missense or nonsense mutations, can alter protein function and lead to various genetic disorders.

Understanding the intricacies of amino acid sequences is essential for comprehending how proteins support and drive life processes, and it is fundamental to fields like biochemistry and molecular biology.