Chapter 10, Problem 1P

Define the following terms as described in this chapter:

balanced polymorphism

heterozygous advantage

balancing selection

intron

hemoglobin tetramer

hereditary anemia

exon

heterozygous

recessive

molecular disease

restriction endonuclease

homozygous

gel electrophoresis

restriction fragment length polymorphism (RFLP)

SNP

electrophoretic mobility

Southern blot

molecular probe

northern blot

antibody probe

western blot

Summary Introduction

To analyze:

Referring to the chapter, define the following terms:

balanced polymorphism

heterozygous advantage

balancing selection

intron

hemoglobin tetramer

hereditary anemia

exon

heterozygous

recessive

molecular disease

restriction endonuclease

homozygous

gel electrophoresis

restriction fragment length polymorphism (RFLP)

SNP

electrophoretic mobility

Southern blot

molecular probe

northern blot

antibody probe

western blot

Introduction:

These are the different terms used in molecular biology. Some terms refer to molecular techniques used to identify target molecules while some refer to the molecules involved in molecular biology studies.

Explanation of Solution

Balanced polymorphism – It describes the end result of balancing selection, a result in which the loss of anallele because of selection against one of its phenotypes isbalanced by natural selection in favor of the allele for anotherphenotype.

Heterozygous advantage –

It refers to the larger relative fitness of heterozygous genotype than the homozygous genotype (it can be either homozygous recessiveor dominant)

Balancing selection –It is a form of natural selection that favors heterozygous genotype and leads to stable equilibrium frequency of alleles in a population.

Intron – An intron is a sequence of nucleotides within a gene that is removed by RNA splicing during formation of mature mRNA. Introns are non-coding regions of DNA.

Hemoglobin tetramer – Hemoglobin is a protein with quaternary structure. The hemoglobin tetramer contains two protein chains $\text{α -}$ globin and $\text{β -}$ globin from each of two different globin genes.

Hereditary anemia –Hereditary anemia is a rare, genetically transmitted blood disorder characterized by premature destruction of red blood cells. Mutations of $\text{α -}$ globin and $\text{β -}$ globin genes often produce hereditary anemia.

Exon – It is a segment of DNA molecule or RNA molecule that contains information coding for a protein. Exons are disturbed by non-coding introns in the DNA sequence.

Heterozygous –Presence of two different types of alleles of a particular gene in a diploid cell is known as heterozygous.

Recessive – It is the type of allele of a particular gene that is not expressed in the presence of other dominant allele. It is a subordinate or submissive allele.

Molecular disease – It is a term that denotes a disease caused by a variation in the molecular structure of a protein. For example – Sickle Cell Disease (SCD)

Restriction endonuclease – Restriction endonucleases are a special class of DNA digesting enzymes that act only on specific DNA sequences. These enzymes are also recognized as molecular scissors.

Homozygous - Presence of two similar alleles of a particular gene in diploid cell is known as homozygous.

Gel electrophoresis - It is an analytical technique used to separate different protein or nucleic acid molecules from one another in an electric field on the basis of their charge, size, and shape.

Restriction fragment length polymorphism (RFLP) – In the presence of SNPs, DNA samples from two individuals exposed to the same restriction enzyme will produce a different number or a difference in length of restriction fragments. These inherited DNA sequence variations are known as restriction fragment length polymorphism (RFLP)

SNP –The most common kind of DNA sequence difference between organisms of the same species is avariation of single nucleotides; this type of difference is known as Single Nucleotide Polymorphism (SNP)

Electrophoretic mobility – It is a term used to describe the rate of a molecule’s electrophoretic migration or its final position in the gel. Electrophoretic mobility of smaller molecules of nucleic acid or protein is higher than that of the larger molecules.

Southern blot –It is a molecular biology method used for detection of a specific DNA sequence in DNA samples. It consists of transfer of electrophoresis – disconnected DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization.

Molecular probe – In molecular biology, molecular probe is a single stranded nucleic acid, labeled with a detectable marker, and it is capable to bind it specific target nucleic acid. It is used to identify target nucleic acid sequence or target proteins following electrophoresis.

Northern blot – It is a molecular biology technique used to study gene expression by detection of isolated mRNA or RNA in a sample by complementary base pairing of probe and a segment of the target nucleotide sequence.

Antibody probe – It is an antibody protein labeled with a detectable marker that attaches to specific target proteins.

Western blot - It is a molecular biology technique used to transfer protein from an electrophoresis gel to a permanent membrane or filter.

Conclusion

Referring to the chapter, given terms are defined.