how many chromosomes do humans have cell

The number of chromosomes is fixed for a given species. It varies from a minimum of two to several hundreds in different species of plants and animals. All individuals of a given species show the same chromosome number in all their body cells. The number of chromo..

Structure of Chromosomes - The chromatin material just before cell division forms into chromosomes. Each chromosome is made up of two longitudinal strands called the chromatids. Structure of Chromosome Each chromatid has a double helical DNA molecul..

Chromosomes and Centromere - Centromere is the primary constriction in the chromatid of a chromosome where the spindle tubules become attached during cell division. A chromosome generally has only one centromere and such a chromosome is described as..

They are mutation involving change in number or structure of chromosomes. Change in number of chromosomes induced by mutagens can lead to aberrant gametes, which when fuse with normal gamete lead to aneuploid zygotes. Changes in chromosomal structure by mutation are b..

Structure of Chromosomes - The most ideal stage to study the structure of chromosomes is the metaphase of mitosis. A metaphase chromosome consist of two identical components called chromatids, which are held together at a specific region called primary constriction. It..

Chromosomes..

..

Types of Cell Division - Cell division is a method by which new cells are originated from pre-existing cells. The formation of daughter amoebae in amoeba, the development of sex cells and the growth of a young animal or plant into an adult, all invo..

The exact number of somatic chromosomes in man was not known till 1956. New techniques of staining chromosomes have revealed the exact number and this have greatly helped the study of human genetics. Using the karyotyping techniques the form, shape and size of all the ..

As can be seen from the human karyogram, the chromosomes are classified into two types, autosomes and sex chromosomes. The autosomes have homologous chromosomes as pairs whereas the sex chromosomes are of two different types - X and Y. A female has ..