Molecular Evolution - creado desde un Mapa Mental

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Molecular Clocks: Technique that uses mutation rates in DNA to estimate the time that two species have been evolving independently.

Emilio Chaparro 4ºC

Neutral Mutation as "Ticks": Have no effect on the phenotype. Accumulate in the DNA of different species at about the same rate. Researchers compare such sequences in 2 species. The more differences, the more time has passed since the species shared a common ancestor.

Gene Duplication: A way in which new genes evolve. Existing genes are duplicated and modified.

Copying genes: Organisms carry copies of various genes. Sometimes they carry 2 or multiple copies of the same gene. This is because sometimes crossing-over involves an unequal swapping of DNA.

Duplicate Genes Evolve: Sometimes extra copies of a gene undergo mutations that change their function, while the original gene is still around. New genes evolve without affecting the original gene function or product.

Gene Families: Multiple copies of a duplicated gene an turn into a group of related genes, called a gene family. They produce similar yet slightly different proteins. Hemoglobins are an example.

Developmental Genes and Body Plans: "Evo-devo" studies the relationship between evolution ad embryological development. How genes determine which parts of an embryo develop arms, legs, and wings.

Hoy Genes and Evolution: Small changes in Hox gene activity during embryological development can produce large changes in adult animals.

Timing is Everything: Each part of an Embryo starts to grow at a certain time, grows for a specific and stops growing at a specific time. Small changes in starting and stopping times can make a big difference in organisms.