Question

I need help with gentics stuff.

Answer 1

11 and 12 seem to be right :) For 13, only organisms which are homozygotic for a certain gene (aa) express a recessive phenotype.
14. This dna exchange between the homologous chromosomes is called crossing-over.   
15. geneticly linked or coupled, the phenomenon is known as genetic linkage
16. and 17. also seem all right :)