1 Muscle weakness and Pain in the joints and Sudden onset of joint pain and Arthritis-like symptoms (3 causes) 2  Muscle weakness and Pain in the joints and Sudden onset of joint pain and Body symptoms (3 causes)  Muscle weakness and Pain in the joints and Sudden onset of joint pain and Bony abnormalities (3 causes)
The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype. In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46.
Humans have diploid cells, meaning each one contains two copies of each chromosome. The number of unique chromosomes, including sex chromosomes, is 23 in humans. This is the n, or haploid number. 2n, or the diploid number is 46, and refers to the actual number of chromosomes in a human cell, including the duplicates.