Concept explainers
Genes that are expressed at all times at relatively constant levels are known as _____ genes.
- inducible
- repressible
- positive
- constitutive
- protein-encoding
Introduction:
Genes are functional units of DNA. Genes carry the hereditary information and pass it from one generation to the next. The availability of genes depends on the location and environment of the cell.
Answer to Problem 1TY
The correct answer is constitutive genes.
Explanation of Solution
Explanation/justification for the correct answer:
Constitutive genes are transcribed continuously in the cell at the constant level like the housekeeping genes transcribe important proteins (actin, GAPDH). These genes are required by all the cells for proper functioning and maintenance of cell.
The explanation for the incorrect answer:
Option A is incorrect.
Inducible genes are expressed in the cell when inducer binds to co-repressor. Inducer presence depends upon the concentration of certain substances in the cell. Thus, this is not the correct answer.
Option B is incorrect.
Repressible genes are expressed only in the presence of co-repressor. Thus, these genes are activated during specific times in the cell. Hence, the option is correct.
Option C is incorrect.
Genes which positively affect the transcription of genes are known as positive genes. Positive genes are not required by each cell. Thus, the option is not correct.
Option E is incorrect.
Protein coding is the process in which the DNA sequence is transcribed into a stretch of a polypeptide. The polypeptide produced through the process may or may not be continuously produced in the cell. Thus, it is incorrect.
The correct answer is d.
Want to see more full solutions like this?
Chapter 12 Solutions
Principles of Biology
- Which of the following is required for positive regulation of gene expression? Question 16 options: repressor activator operator stop codonarrow_forward"once cells have differentiated to their final specialized forms, they never again alter expression of their genes" is true or false.arrow_forwardTrue or false: For each protein-coding gene, there is one promoter and one enchancer that act as regulatory elements for that gene.arrow_forward
- Which of the following epigenetic changes could lead to reduced transcription of a particular gene?. Please make sure to select all correct answersarrow_forwardWhich of the following general transcription factors aids polymerase binding in the right direction on promoters? Group of answer choices TFIID TFIIB TFIIA TFIIFarrow_forwardWhich of the following DNA regions is NOT involved in gene expression regulation in eukaryotes? Promoter-proximal elements Promoter Enhancer Operator **Enhancer is incorrectarrow_forward
- Gene expression is initiated largely in response to changes in the ____________________________ in prokaryotes as opposed to changes affecting the homeostasis of the whole organism in eukaryotes.arrow_forwardA researcher that uses mouse models to understand protein function in the immune system ,genetically engineered one of her mice to be missing a specific protein known as I TK.There is a special term to describe removal of gene function to study the role of the gene.This term is ………..?arrow_forwardTrue/False questions Promoter is a protein that regulates transcription. True/False Bacterial genes are almost always part of operons. True/False RNA polymerase cannot bind to the promoter when repressor is bound to the operator. True/False Proteins are polymers of amino acids connected by phosphodiester bonds. True/False First amino acid of any protein is always methionine. True/Falsearrow_forward
- A protein binds a DNA sequence several hundred base pairs upstream of a promoter in a eukaryotic organism. This results in an increased rate of transcription of the gene. What type of protein is this? Group of answer choices Activator Silencer Enhancer Repressorarrow_forwardLabel promoter and terminator regionsarrow_forwardWhich of the following is NOT dependent on its distance from the start site of transcription?Question 18 options: TATA box -10 and -35 sequence Response Element (RE) stretch of pyrimidinesarrow_forward
- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning