Lecture 11: Introducing Variation (Exam 2) Flashcards
What would happen if DNA was replicated with perfect fidelity
there would be no evolution
What mutation is and generally how it occurs (5A vocab)
- mutation is an alteration in the DNA sequence
1. altered nucleotide sequence
2. different amino acids make up primary structure
3. new protein produced
codon
sequence of 3 nucleotides
amino acid
3 letter name
the genetic code is said to be ______ , meaning
degenerative; different codons specify the same amino acid
the fitness effects of most mutations
most mutations are bad; 20% lethal, 40% neutral
types of mutation
- substitution, insertion, deletion
how gene duplication can lead to proteins with new functions
- experiment was whole gene duplication in common ancestor of animals
- one good copy means second copy can mutate without killing the organism
the production of genetic variation in sexual and asexual populations
- asexual populations produce **identical daughter cells ** and mutation is only source of genetic variation
- sexual populations produce haploid recombinant gametes that fuse with other gametes; new combinations of the same alleles
the fundamental source of genetic variation for all life
mutation
the second assumption of HWE and the interpretation of mutation simulations
- 2nd assumption is no mutation
- interpretation of mutation simulations??
standing genetic variance
having multiple alleles at the same locus
what is and isn’t random about mutation
- with respect to outcome, random
- with where and how mutations occur, not random
Mullers Ratchet
- process of organisms getting more masked deleterious mutations
genetic load
- amount of deleterious recessive mutations hidden behind dominant functioning genes
