Question

In ideogram, chromosomes of an organism are arranged according to their
A. Increasing size
B. Decreasing size
C. Position of centromere
D. Number of chromosome

Answer 1

Hint: Idiogram used a karyotype to arrange the chromosome pairs in a diagrammatic representation. In the ideogram of humans, the first chromosome is the first one and the 21st chromosome is the smallest.

Complete answer: Ideograms are the diagrammatic representation of karyotype displaying all the morphological features of the chromosomes. The chromosomes are segregated on the basis of the position of centromere sorted according to the decreasing size of the chromosomes.

Idiograms of a female human is given above.
Scientists around the globe need an up to date mapping system which allows them to refer to a specific part of a particular chromosome with extreme accuracy. This is where idiograms come into play. They provide a pictorial reference that is useful for identifying and positioning individual genes on known chromosomes. They also help in identifying certain abnormalities associated with chromosomes. Hence, they are a way to figure out genetic and chromosomal disorders in species. Also, the famous Human Genome Project is used to make ideograms, making them a very resourceful source of information related to chromosomes worldwide. They provide a clear and quick representation for easy research.
Hence option B is correct.

Note: Ideograms are available on many online platforms, making it more acceptable. Ideograms are another sorted form of karyotypes. Karyotypes are the mapping of chromosomes in which measurement of characteristics like chromosome number, their size and symmetry, and many more.