Genes are DNA or RNA, they act as instructions to make molecules called proteins! They are found in chromosomes and there main objective is to carry out information that determines your characteristic traits that are inherited from your parents!
Hope that helps :))
Mitosis is the division of the nucleus while cytokinesis is the division of the cytoplasm
20. The answer is 1 (Precambrian)
21. The answer is 4 (Pennsylvanian)
22. The answer is 2 (Bony Fishes, Dinosaurs, and Mammals)
23. The answer is 2 (Reptiles)