Quest 3 Flashcards

Question

What are Codons?

Answer 1

bases that start/stop translation

Answer 2

prevents the production of certain proteins by binding and destroying them.

Answer 3

converts genetic instructions (mRNA) into functional proteins.

Answer 4

set of rules used by living cells to translate information encoded within genetic material (DNA or mRNA) into proteins.

Answer 5

Different groups favor certain codons more than others.

Answer 6

All amino acids have codons to code for specifically

Answer 7

heritable mechanisms that alter gene expression without changes to the DNA. Typically on the cellular level, some cases found across meiosis to the next generation.

Answer 8

often stops transcription by blocking promoters and RNA polymerase

Answer 9

1. Recombination (within pop.) 2. Mutation (within pop.) 3. Migration (outside population) 4. Lateral Gene transfer (outside population; usually in bacteria)

Answer 10

Nonsense (genetic change where a single nucleotide creates a stop codon), synonymous (alters the sequence of a gene but does not change the amino acid; silent), nonsynonomous (changes the amino acid sequence; could be damaging)

Answer 11

the proportion or percentage of individuals in a population that exhibit a specific, distinct phenotype controlled by one or a few genetic loci - (Ex: aloe spiral direction)

Answer 12

- This Null Model tells us what happens to a population if none of the evolutionary processes are at work (i.e. selection) - Hardy and separately Weinberg (and William Castle of Ohio in 1903), wanted to know what happens to alleles passed from parent to offspring if only transmission genetics are in play.

Answer 13

1. Individual-level thinking: What gametes and offspring are produced, in what frequencies from a given pair of parents? 2. Population-level thinking: How doe the characteristics of the population change over time as the result of evolutionary processes?

Answer 14

1. Frequencies of alleles p and q do not change over time without eco processes. Also used as A1 and A2. 2. Given allele frequencies (freq. of p and q) and random mating we can predict the equilibrium genotype frequencies. p^2 2pq q^2 or A1A1, A1A2, A2A2 the Hardy-Weinberg equilibrium freqs. 3. If there are no evolutionary processes at work then a pop. not in HWE will go to HWE in one generation

Answer 15

1. No Natural Selection - there is no selection acting on the trait or trusts in question 2. Random mating (no sexual selection) - No assortative mating, all mating is random with respect the the trait in question 3. No Mutation - no mutation at the locus or trait 4. No migration AKA Gene Flow 5. Population is infinite, so no genetic drift

Answer 16

The fitness associated with a trait is not directly dependent on the frequency Ex: Directional Selection (the rock pocket mouse)

Answer 17

1. Directional selection - For one extreme against the other 2. Stabilizing selection - for the middle and against both extremes 3. Disruptive selection - for both extremes against the middle

Answer 18

1. is a genetic condition where an individual with two different versions of a gene (heterozygote, e.g., 𝐴𝑎) is more fit, stronger, or better adapted than individuals with two identical versions (homozygotes, e.g., 𝐴𝐴 or 𝑎𝑎) - Ex: if you have sickle cell, you're immune to malaria 2. an evolutionary mechanism where natural selection maintains two or more different alleles (gene variants) in a population at stable frequencies, preventing any single allele from being eliminated

Answer 19

- Worst case scenario - is a genetic phenomenon where heterozygous individuals (𝐴𝑎) have lower fitness (survival or reproductive success) than both homozygous genotypes (𝐴𝐴 and 𝑎𝑎).

Answer 20

Frequency dependent selection is when the cost or benefit associated with the trait changes depending on its frequency in the population. - Positive - fitness of the trait increases as the frequency increases - Negative - when the fitness associated with the trait decreases as the frequency increases

Answer 21

Viability selection improves an organism's probability of surviving from zygote to adult, while fecundity selection increases the rate of reproduction and offspring production.

Answer 22

When the rate of deleterious allele elimination = rate of new allele creation via mutation q=sqrt (u/s)

Answer 23

Non-random mating: individuals selecting partners based on specific phenotypes, proximity, or genetic relatedness. Assortative mating: individuals with similar phenotypes (observable traits) or backgrounds (e.g., education, ethnicity) pair together more frequently than by chance. Disassortative mating: individuals with dissimilar phenotypes or genotypes mate more frequently than expected by chance. Causes excess of heterozygotes. Inbreeding: causes genotype frequencies to change in favor of homozygotes while the allele frequencies do not change at all. Inbreeding Depression: the result of selfing and reproduction with genetic relatives. It happens as a consequence of increasing homozygosity.

Answer 24

1. It causes gene pools between populations to be more similar 2. Adds genetic variation to populations

Quest 3 Flashcards

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