The pairing of homologous chromosomes during prophase 1 lets the crossing over to occur and crossing over between non-sister chromatids, in turn, lets the recombination to occur. Crossing over occurs at points called chiasma, which are created between non-sister chromatids. Chiasma lets the exchange of DNA segments between non-sister chromatids. This exchange of DNA segments produces new combinations of alleles among the offspring, which is identified as genetic recombination.
Complimentary Guest Upgrades are paper upgrade coupons given to MVP Gold members to upgrade friends or family members who are not traveling with them, or for their own use for immediate upgrade when not purchasing a qualifying fare.
The Ravelli AVTP Professional 75mm Video Tripod is a heavy duty professional level product at a consumer level price. It features extreme durability, an impressive set of features as well as excellent handling and performance. I do recommend buying this product and I personally use it as my primary tripod for video use.