11. Mendel predicted that there are “units of heredity” which we now call __________. 12. A version or variant of a gene that produces a specific trait is called an _________. 13. A recessive phenotype can only be displayed if the genotype is heterozygous. 14. The chromosomes that underwent ____________________ during meiosis are called recombinant chromosomes, because they contain a region that has recombined to form a new pair of alleles. 15. When genes do not assort independently, the genes are said to be _________________ on the same part of the chromosome so they get passed on together. 16. A ____________ is a segment of DNA on a chromosome that codes for a particular trait. 17. Most sex-linked genes are on the____ chromosome, simply because they are built of much more DNA. However, _________ are more likely than _________ to exhibit sex-linked traits.