Table of Contents
What is Plectonemic coil?
A type of coiling of a double‐stranded helix in which the two strands are intertwined, i.e. they may not be separated without uncoiling. From: plectonemic coiling in Oxford Dictionary of Biochemistry and Molecular Biology »
What is Paranemic?
A DNA structure is defined as paranemic if the participating strands can be separated without mutual rotation of the opposite strands.
Which type of coiling occurs in DNA?
The type of coiling which occurs during the process of mitosis is plectonemic coiling. DNA supercoiling can be defined as the over- or under-winding of the DNA strand, and it can be expressed as strain of one strand on the other strand.
What is coiling of chromosomes?
The major coils do not prevent free separation of chromatids at the first meiotic division. After the pairing of coiled homo- logues at meiosis, the chromosomes elongate and produce a “relational” coiling at pachytene. Each chromosome now divides so that relational coiling exists in the chromatids of each homologue.
What is Plectonemic in biology?
In plectonemic coils, the chromosomal fibrils are closely intertwined and they cannot be separated easily. The degree of coiling during cell division depends on the length of chromosomes. The type of coiling during mitosis is plectonemic.
What is extensive coiling?
Answer: extensive coiling means that it is wound up into circular rings one above the other, the small intestine is extensively coiled.
What does the Synaptonemal complex do?
Synaptonemal complex: A protein structure that forms between two homologous chromosomes during meiosis and that is thought to mediate chromosome pairing, synapsis, and recombination.
What is Paranemic and Plectonemic?
Response. Plectonemic coiling takes place during mitosis, in which sister chromatids are tightly coiled upon each other and are not easy to separate. Paranemic coiling found in meiosis where the two strands are loosely coiled, making them easier to separate.
Why do chromosomes coil in meiosis?
Chromosomes are coiled structures made of DNA and proteins. Chromosomes are the form of the genetic material of a cell during cell division. It is this coiled structure that ensures proper segregation of the chromosomes during cell division.
What is folded Fibre model?
Ø The Folded Fibre Model of chromosome was proposed by DuPraw in 1965. Ø He published this model based on his studies on human chromosomes using electron microscope. Ø The important features of Folded Fibre Model of Chromosome are: Each chromosome contains a single but long and coiled chromatin fibre.
Which is the most coiled part of the small intestine?
ileum
The ileum. The jejunum and the ileum are the greatly coiled parts of the small intestine, and together are about 4-6 metres long; the junction between the two sections is not well-defined.