Answer;
-23 in males
In humans, 23 in males is the only homologous chromosome pair that isn't the same.
Explanation;
-In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46.
-Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females. Females have two copies of the X chromosome, while males have one X and one Y chromosome.
-The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes.
Mitosis creates two identical daughter cells that each contain the same number of chromosomes as their parent cell. ... These new combinations result from the exchange of DNA between paired chromosomes. Such exchange means that the gametes produced through meiosis exhibit an amazing range of genetic variation.
https://www.nature.com/scitable/topicpage/replication-and-distribution-of-dna-during-meiosis-6524853
Cell membranes serve as barriers and gatekeepers. They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot.