Biology 1001A Chapter Notes - Chapter 9.1-9.3: Nuclear Membrane, Kinetochore, S Phase

• School: Western University
• Department: Biology
• Course: Biology 1001A
• Professor: Beth Mac Dougall- Shackleton

Document Summary

The process by which the combinations of alleles for different genes in two parental individuals become shuffled into new combinations in offspring individuals. Genetic recombination requires the following: two dna molecules that differ from one another, a mechanism for bringing the dna molecules into close proximity, a (cid:272)olle(cid:272)tio(cid:374) of e(cid:374)z(cid:455)(cid:373)es to (cid:862)(cid:272)ut,(cid:863) (cid:862)e(cid:454)(cid:272)ha(cid:374)ge,(cid:863) a(cid:374)d (cid:862)paste(cid:863) the dna (cid:271)a(cid:272)k together. The sugar phosphate backbone is held together by strong covalent bonds, whereas the bases pair with their partners through relatively weak hydrogen bonds. Regions of dna that are very similar, but not identical, in the sequence of bases = homologous. Homology allows different dna molecules to line up and recombine precisely. Once homologous regions of dna are paired, enzymes break a covalent bond in each of the four sugar phosphate backbones. Cutting and pasting four dna backbones results in one recombination event. Genetic recombination that could lead to evolutionary changes.