Lecture 11: Introducing Variation (Exam 2) Flashcards
(15 cards)
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
