✨BIO EXAM 5 Free form notes✨

Date 11/11/24 - MOODLE ACTIVITY DUE NEXT MONDAY (on evolution)

●Evolution both patten and process

●Darwin drew from the study of FOSSILS, remains or traces of organisms from the past

●Many fossils are found in sedimentary rock, which appears in layers called strata

●Darwin had a consuming interest in nature throughout his life.

  • studied med, didn’t like it and switched to theology

  • After graduation, he took a position as naturalist on a five-year, worldwide voyage on the HMS Beagle

●Decent with mods. by natural selection explains 3 broad observations

  • the unity of life

  • the diversity of life

  • the ways organisms are suited to life in their environments

●Darwin used descent with modification to describe his view of life EX pic:

Date 11/13/2024 Chapter 22

● Humans mod. species through artificial selection, breeding only individuals with desired traits

● Darwin drew 2 inferences from two observations

  • Observation1; members of a pop. often vary in their inherited traits

  • Observation2; all species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce

  • Inference1; individuals w/ inherited traits that increase survival and reproduction in an environmental tend to produce more offspring than other individuals

  • inference2; The unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations

●Individuals do not evolve; it’s the pop. that evolves over time

●Nat. select can only increase or decrease heritable traits that are variable in a population

THE EVO. OF MDR

●the bacterium staphylococcus aureus often on skin or nasal passages of about1 in3 peeps

-When it becomes staph infection + MDR you die.

●in 1943 penicillin first widely used antibiotic

●Methicillin works by inhibiting an enzyme used by bacteria to make cell walls

●MRSA bacteria are able to use a diff. enzyme that’s not affected by methicillin

●Resistance increases in the presence of methicillin BC MRSA strains are more likely to survive and reproduce than nonresistant

●MDR strains have evolved through the exchange of resistant genes b/t individuals

=

●Comparative embryology reveals anatomical homologies not visible in adults

Date: 11/15/2024

●Understanding continental drift and modern species distribution helps predicts when and where different groups evolved

●In science a theory accounts for many observation and data and attempts to explain and integrate a great variety of phenomena

●Darwin’s theory of evolution by natural selection integrates diverse areas of bio. study and stimulates many new research questions

●ongoing research adds to our understanding of evolution

● Natural selection acts on individuals, but only populations evolve

  • Ex. medium ground finches

  • consider the graph of beak size. What observations do you have?

  • What event might have impacted beak depth?

  • Why do you think it might of occurred

    The finches after nat. selection

●MICROEVOLUTION

  • Change in allele frequencies in a pop. over gens. (evolution at smallest scale)

  • 3 mechanisms cause allele freq. to change

  • (nat. select., Genetic drift, Genetic flow)

●1st req. fro evolution by nat. select = Genetic variation

● Monogenic trait- phenotypic diff. determined by one gene

●Polygenic trait- Phenotypic differences determined my two or more genes

●Genetic variations are produced rapidly in organisms with SHORT GENERATION TIMES

●New alleles arise by mutations

-changes in the nucleotide sequence if DNA

●Examples of causes of mutations'

-Replication errors

-Exposure to certain types of radiation

-Exposure to certain types of chemicals

●Even a point mutation can have significant impact on phenotype

-Point mutation= change in one

●Most mutations that alter phenotype are at least slightly harmful

●Recessive harmful mutations can be hidden from selection in heterozygous individuals

●Not all mutations are harmful

-Neutral variation

+Variation w/ no selective advantage or disadvantage

●only mutations in cell lines that create gametes are passes to offspring

● LARGE CHROMOSOMEAL ALTERATIONS are usually harmful

-rearrangements

-deletion

-duplication

●Duplication of small segments of DNA including genes

-key potential source of genetic variation

●If dupllicated genes persists pver generations

-mutations can acumulate and new functions may arise

●Mutation rate

-low in eucariotes/plants

-av. aprx. 1 in 100,000

●Prokaryotes have lower rates •(1 in 105-108)

●•Most genetic variation in sexually reproducing organisms results from recombination of alleles

DATE: 11/18/24

Medical mission trip to Honduras - hurricane hit the hospital -hospital okay and peeps, but yikes. — also Dr Krepps had said you may get to do stiches, injection, tooth removal,

●Allele frquency

-for diploid = total # of alleles at a locus = total # of individuals

●BY convention if there are two alleles at a locus p and q are used to rep. their frequencies

●the frequency of all alleles in a pop. will add up to one

•The frequency of genotypes can be calculated

–CRCR = p × p = p2 = 0.8 × 0.8 = 0.64

–CRCW = pq + qp = 2pq = 2 × 0.8 × 0.2 = 0.32

–CWCW = q × q = q2 = 0.2 × 0.2 = 0.04

•The frequency of genotypes can be confirmed using a Punnett square

● Hardy-Weinberg Equilibrium p²+2pq + q² = 1 Think of like a putnent square

● A pop. can be in equilibrium for some genes but not others

●This can be used to determine if you’ll pass on genetic problems to your kids

YOU WILL HAVE TO KNOW THIS MATH PARA TUS EXAMEN *SOB*

DATE 11/20/24

Natural selection is based on differential success in survival and reproduction

Natural selection can cause adaptive evolution a process where traits that enhance survival

GET NATURAL SELECTION, GENETIC DRIFT, AND GENE FLOW FROM PWER POIN!

genetic drift is more sig. in sm. pop. - is random -can lead to loss of gen variation - can be harmful and cause alleles to become fixed

DATE 11/22/24

Ch. 24

●Species = laten for kind or appearance

●Comparisons of physiology biochemistry and DNA sequences generally confirm that morphological distinct species are discrete groups

●Biological spieces concept

  • must be able to mate

  • produce viable and fertile offspring

  • should not produce viable fertile offspring with members of other groups

●Formation of new species hinges on reproductive compatibility

●Prezygotic barriers = block fertilization from occurring by

–Impeding different species from attempting to mate

–Preventing the successful completion of mating

–Hindering fertilization if mating is successful

●Postzygotic Barriers =prevent hybrid zygotes from developing into viable, fertile adults through

–Reduced hybrid viability

–Reduced hybrid fertility

—Hybrid breakdown

Date 12/2/24

●Final will be like a reg. exam.

●ch25 will be on the Moodle activity

●The evolutionary Hx (hypothesis) of group of organisms are showed by phylogenic tree

●A phylogenetic tree reps a hypothesis about evolutionary relationships

●Sister taxa = two things that share a common ancestor that’s not shared by another group

●tree branches can be rotated around a branch point

●Basal taxon= lineage that diverges form the others early in the Hx but remains unbranched

●APPLYING PHYLOGENIES

-can be used for crops

-genetic engineering

●Systematists use data in the morphology genes and biochem of —

● in some cases morphological differences can be reall diferent, but the DNA stuff is real simallaer. Thing those twims that look sups diff (Like the black and white ones)

●Complexity of characters being compared can help distinguis b/t homology and analogy

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