What is the primary constriction of a chromosome?
Primary constriction is the basic centromere by which the early new chromatids (newly formed chromosomes) remain attached to each other. Its capacity is to empower the development of the chromosome during the anaphase phase of the cell division.
What is constriction in a chromosome?
The centromere is the lighter staining region on the chromosome of a cell which appears as a constriction. They are also known as a primary constriction or kinetochore. It is a specialized DNA sequence that links a pair of sister chromatids where the spindle fibres are attached during cell division.
What is primary and secondary constriction in chromosome?
Secondary constrictions are the constricted or the narrow region found at any point of the chromosome other than that of centromere (primary constriction). The difference between the two constrictions can be noticed during anaphase, as chromosomes can only bend at the site of primary constriction.
Which part of chromosome is known as primary construction?
Complete answer: Option A: A chromosome consists of two identical halves, the chromatids which are held together at one point called centromere. The centromere appears as an arrow region called the primary constriction of the chromosome.
Which is the primary construction?
Primary Construction Contracts means the EPC Contract, any contract or agreement between Contractor and any Subcontractor, and all agreements and documents referenced therein. Primary Construction Contracts means, collectively, the Phase I Primary Construction Contract and the Phase II Primary Construction Contract.
What does the term constriction mean?
1a : to make narrow or draw together Smoking constricts blood vessels. b : compress, squeeze constrict a nerve These shoes are too small and they constrict my feet. 2 : to stultify, stop, or cause to falter : inhibit The expectation of violence constricts our lives.— Marge Piercy. intransitive verb.
What is a constriction on a chromosome bound to a disk?
The centromere is the region where two sister chromatids of a chromosome appear to be joined or held together during mitotic metaphase. When chromosomes are stained they typically show a dark sustained region that is the centromere. The centromere is also known as the primary constriction.
Is primary constriction same as centromere?
Centromeres were first thought to be genetic loci that direct the behavior of chromosomes. … Regarding mitotic chromosome structure, centromeres represent a constricted region of the chromosome (often referred to as the primary constriction) where two identical sister chromatids are most closely in contact.
What is the function of primary constriction and secondary constriction of chromosome?
The difference between the two constrictions can be noticed during anaphase, as chromosomes can only bend at the site of primary constriction. Secondary constrictions are useful in identifying a chromosome from a set.
Which chromosome shows secondary construction?
In human beings, secondary constriction is nucleolar organizer in chromosome number 13, 14, 15, 21 and 22. Secondary constriction appears due to uncoiling of chromatin which has rRNA genes which are undergoing transcription rapidly.