Chromosome pairing refers to the lengthwise alignment of homologous chromosomes at the prophase stage of meiosis. … The responsible cell division is meiosis and the mechanism is pairing/synapsis and subsequent separation of homologous chromosomes.
What is the main difference between Chromatin and chromosomes?
Chromatin is a complex formed by histones packaging the DNA double helix. Chromosomes are structures of proteins and nucleic acids found in the living cells and carry genetic material. Chromatin is composed of nucleosomes. Chromosomes are composed of condensed chromatin fibers.
Do body cells have paired chromosomes?
Chromosomes of body cells are found in pairs. … Chromosomes in sex cells are not paired. Therefore, a gamete has half the number of chromosomes that a body cell has. For example, a human body cell has 46 chromosomes.
Why is pairing up of chromosomes important?
Pairing of homologous chromosomes is an essential feature of meiosis, acting to promote high levels of recombination and to ensure segregation of homologs.
What is it called when homologous chromosomes pair up?
The tight pairing of the homologous chromosomes is called synapsis. In synapsis, the genes on the chromatids of the homologous chromosomes are aligned precisely with each other.
Can a chromosome have one chromatid?
When fully condensed, replicated chromosomes appear as thick X-shaped structures that are readily observed under the microscope (see figure below). Chromosomes can have 1 or 2 chromatids, depending on whether they have replicated.