Question

What is a physical map of a chromosome?

A) identification of the length of the chromosome by comparing it to known chromosomes
B) description of the base pair difference between two loci
C) determination of the p and q arm length
D) determination of where the centromere lies
E) determination of how far apart genes are my recombination mapping

Answer 1

A physical map of a chromosome provides information about the physical distance between genetic markers and the number of nucleotides. It uses methods such as cytogenetic mapping, radiation hybrid mapping, and sequence mapping to determine these distances. Cytogenetic mapping uses stained chromosome sections, radiation hybrid mapping breaks DNA using radiation, and sequence mapping uses DNA sequencing technology.

Step-by-step explanation:

A physical map of a chromosome provides detail of the actual physical distance between genetic markers, as well as the number of nucleotides. There are three methods used to create a physical map: cytogenetic mapping, radiation hybrid mapping, and sequence mapping.

Cytogenetic mapping uses microscopic analysis of stained chromosome sections to determine the approximate distance between genetic markers. Radiation hybrid mapping breaks DNA using radiation and is unaffected by recombination frequency. Sequence mapping uses DNA sequencing technology to create physical maps.