= Gene expression is
the process by which the information encoded in a gene is used to direct the assembly of a protein molecule
. The cell reads the sequence of the gene in groups of three bases. Each group of three bases (codon) corresponds to one of 20 different amino acids used to build the protein.
What is gene expression?
Listen to pronunciation. (jeen ek-SPREH-shun)
The process by which a gene gets turned on in a cell to make RNA and proteins
. Gene expression may be measured by looking at the RNA, or the protein made from the RNA, or what the protein does in a cell.
What is gene expression example?
Some simple examples of where gene expression is important are:
Control of insulin expression
so it gives a signal for blood glucose regulation. X chromosome inactivation in female mammals to prevent an “overdose” of the genes it contains. Cyclin expression levels control progression through the eukaryotic cell cycle.
What is gene expression kid definition?
Gene expression is
the process by which the heritable information in a gene, the sequence of DNA base pairs, is made into a functional gene product
, such as protein or RNA. The basic idea is that DNA is transcribed into RNA, which is then translated into proteins.
What is gene expression and why is it important?
Genes encode proteins and proteins dictate cell function
. Therefore, the thousands of genes expressed in a particular cell determine what that cell can do.
What are the two stages of gene expression?
It consists of two major steps:
transcription and translation
. Together, transcription and translation are known as gene expression. During the process of transcription, the information stored in a gene's DNA is passed to a similar molecule called RNA (ribonucleic acid) in the cell nucleus.
What increases gene expression?
Activators
enhance the interaction between RNA polymerase and a particular promoter, encouraging the expression of the gene. Activators do this by increasing the attraction of RNA polymerase for the promoter, through interactions with subunits of the RNA polymerase or indirectly by changing the structure of the DNA.
What is the purpose of gene expression?
Gene expression is a tightly regulated process that
allows a cell to respond to its changing environment
. It acts as both an on/off switch to control when proteins are made and also a volume control that increases or decreases the amount of proteins made.
What controls gene expression?
Gene expression is primarily controlled
at the level of transcription
, largely as a result of binding of proteins to specific sites on DNA. … The regulator gene codes for synthesis of a repressor molecule that binds to the operator and blocks RNA polymerase from transcribing the structural genes.
How many genes do humans have?
An international research effort called the Human Genome Project, which worked to determine the sequence of the human genome and identify the genes that it contains, estimated that humans have
between 20,000 and 25,000 genes
. Every person has two copies of each gene, one inherited from each parent.
How do genetics work?
Genetics is
the study of how different qualities, called traits, are passed down from parents to child
. Genetics helps explain what makes you unique, why family members look alike, and why some diseases run in families. When we trace the paths of these qualities, we are following packages of information called genes.
What happens during translation?
During translation,
ribosomal subunits assemble together like a sandwich on the strand of mRNA
, where they proceed to attract tRNA molecules tethered to amino acids (circles). A long chain of amino acids emerges as the ribosome decodes the mRNA sequence into a polypeptide, or a new protein.
What are the advantages of only expressing some genes?
In addition, only expressing a subset of genes in each cell
saves space because DNA must be unwound from its tightly coiled structure to transcribe and translate the DNA
. Cells would have to be enormous if every protein were expressed in every cell all the time.
Why is it important for an organism to control expression of its genes?
The regulation of gene expression
conserves energy and space
. It would require a significant amount of energy for an organism to express every gene at all times, so it is more energy efficient to turn on the genes only when they are required.
How does gene expression occur?
Gene expression is the
process by which the information encoded in a gene is used to direct the assembly of a protein molecule
. The cell reads the sequence of the gene in groups of three bases. Each group of three bases (codon) corresponds to one of 20 different amino acids used to build the protein.
What are the three steps of gene expression?
Transcription takes place in three steps:
initiation, elongation, and termination
. The steps are illustrated in Figure 2. Figure 2. Transcription occurs in the three steps—initiation, elongation, and termination—all shown here.
