What Is Satellite Dna Class 12

Repetitive dna is the nucleotide sequences repeating over and over again in the genome of the organisms.

What is satellite dna class 12.

Their characteristic that makes them useful for identification is that. Dna satellites are of two types i e. Thousands of genes are located on chromosomes repetitive dna introns and regulatory sequences are considered as noncoding dna in the genome. Key difference repetitive dna vs satellite dna genomic dna is mainly composed of coding dna and noncoding dna.

This structure is described as a double helix as illustrated in the figure above. Coding sequences are known as genes. Dna fingerprinting is a technique that shows the genetic makeup of living things. Satellite dna consists of very large arrays of tandemly repeating non coding dna satellite dna is the main component of functional centromeres and form the main structural constituent of heterochromatin.

Satellite dna regions are stretches of repetitive dna which do not code for any specific protein. In a dna strand the nucleotides are linked together by a glycosidic bonds b phosphodiester bonds c peptide bonds d hydorgen bonds. In cscl density gradient analysis they appear as light bands. Satellite dna is a type of repetitive dna and it classified into minisatellites microsatellites and minivariant repeats based on the number of repetitive units the number of base pairs in each unit and the base composition of the units.

It is the non coding dna with multiple copies of identical sequences which may lie in tandem or interspersed. It is a nucleic acid and all nucleic acids are made up of nucleotides the dna molecule is composed of units called. This has been helpful in dna fingerprinting. Students can solve ncert class 12 biology molecular basis of inheritance mcqs pdf with answers to know their preparation level.

It is a method of finding the difference between the satellite dna regions in the genome what is dna fingerprinting. Satellites are short sequences of dna repeated again and again to form long sequences. Dna fingerprinting is the method followed by scientists to identify particular individuals as per their dna map. Molecular basis of inheritance class 12 biology mcqs pdf.

The dna structure can be thought of like a twisted ladder. These can be few base pairs to hundreds or thousands of base pairs long. Repetitive dna and satellite dna are two types of dna found in the genome of most eukaryotes the main difference between repetitive dna and satellite dna is that repetitive dna is small sequences of dna that are repeated hundreds or thousands of times whereas satellite dna is highly repetitive dna sequences constituting a considerable part. Significance of satellite dna in dna fingerprinting a dna satellite is a region that consists of short dna sequences repeated many times.

Variation in the lengths of these satellite dna is unique to every human being. Main difference repetitive dna vs satellite dna. The name satellite dna refers to the phenomenon that repetitions of a short dna sequence tend to produce a different frequency of the bases adenine cytosine guanine and thymine and.