BIO1040 Exam 1

methodical naturalism *

explain how the world come to be with myths
greek philosophers explain using physical laws

scientific method *

observe
form hypothesis
test hypothesis
refine hypothesis
theory and further testing

hypothesis * is a

conjecture
and has to be flasifiable and requires control and also has to be repeatable

scientific theories *

based on tested hypothesis/facts

can you prove things in science

false, they are tentative

laws *

summaries of a large collection of facts which are strongly supported by empirical evidence

what do laws not provide

no explanations, but are important components of theories

scientific enquiry

observations → explanations → hypothesis → theories
or
observations → laws → theories

Darwin

calculated it takes 200k years to form rocks

Linaeus

classified animals but the definition may be vague therefore not the best way of classification

Buffon

argued life changes over 70k years (which is the age of the earth he calculated)

author of the encyclopedia

Buffon

Curier

discovered new species such as the extinct mastodon

Smith

produced first detailed geological map

Lawmark

argued complex species came from simple
primitive life was generated spontaneously
extinction DNE, instead evolution takes place

published origin of species
collected maintain of evidence to present his theory
rejected Lawmarck
established that evolution can be studied scientifically
NS and homology

Darwin

NS *

the driver of evolution
natural and observable process
driven by struggle for existence

the process of NS

if trait good → more offspring with trait → more common trait
takes place over countless generations

fossils *

mineralized evidence of a once living organism

where are fossils mostly found

sedimentary rocks

paleontologists

people who study fossils

radioactive dating *

radioactive atoms decay into other elements at a precise rate
measuring product of decay gives estimation of how old rocks are

the oldest fossil found are __ years old

3.5 billion and earth is around 4.567 billion years old

carbon 14 is not used for fossils because

the half life for carbon 14 is too short to be applied to fossils as fossils are usually a lot older than that (typically 10k+ years)

ecological analogues *

unrelated organisms from different continents show adaptation to same niches

morphology

the study of the structures and forms of the organisms

morphology shows that

physical traits can change rapidly and in a specific direction

vestigial structures

traits that have lost their original function

vestigial genes

genes that have lost their ability to code for proteins

T/F: number of dna equals complexity

false

domestication is a form of ___ selection

artificialar

artificial selection is used to

show change in species in a short time
produce bigger fruits

mutant *

new characteristic or traits not formed in the parental type

silent mutations *

mutations that dont have any effect

T/F: mutations can be positive

true

T/F: size of mutation equals to the size of effect

false

gene duplications *

common origin of new jeans, not subjected to NS and free to evolve
produces gene families

heterozygosity *

mean percentage of individual heterozygous per locus
measure of gene variation

the higher the heterozygosity

the better for the survival

more variation

more gene influence

mendel’s laws

law of segregation and law of independent assortmentl

law of segregation

pair of alleles for a trait and only 1 from each parent is passed onto the offspring l

law of independent assortment

alleles for different traits are passed onto offspring independently of one another

genotype

gene you carry

phenotype

gene you express like physical traits

phenotypic variation

to be heritable - must be genotypic

non-genotypic variation

from evolution factors and has no role in evolution and not heritable

molecules of genetics

proteins, dna, rna

weight of genes

proteins make up dry weight
water makes up cell mass

proteins *

are chains of amino acid that performs tasks based on their shapes which is based on sequence of amino acid

DNA

made of nucleotides joined by hydrogen bonds

nucleotides

contains phosphate group, nitrogenous base (ACTG), and glucose

transcription

DNA to RNA introns removed

translation

RNA into nucleotide groups which builds amino acid chain

2 drivers of evolution *

genetic drift and natural selection

genetic drift

can have a large effect on small population
can oppose natural selection
random

genetic drift acting on small and isolated population

why can lethal alleles remain high frequencies in some extreme cases?

genetic drift makes some alleles fixed and some are lost

what may cause heterozygosity to decrease

drivers of genetic drift *

founder effect and bottleneck effect

population bottleneck *

low diversity need intervention (usually when there’s a significant reduction in size due to an event)

imbreeding *

increases homozygosity

founder effect

colonization by a few individual

side effects of imbreeding

homogenous deletetrious genes leads to imbreeding identity

extinction vortex *

habitat destruction reduces and fragments population
increases homozygosity
decreases heterozygosity
lowers diversity
population goes exintct

positive selection

increases fitness of genotype
may not always be positive if there’s changes to ie environmental niches

negative selection

decreases fitness and leads to lethal mutations
no descendants = 0 fitness

selection coefficient *

describes fitness reduction
if = 0 no selection
if positive increases fitness
if negative decreases fitness

is natural selection random *

NS is not random and is more effective in big population

strength of selection, amount of variables. how much variable is inherited, and size of population

factors that may affect the speed of NS

overdominance *

heterozygote > homozygote for fitness → balancing selection

negative frequency dependent selection

rare phenotype have selective advantage
results in intermediate frequency of phenotype
hair color is an example

mutation selection balance

mutation → NS remove bad mutation → new bad mutation → removal of bad mutation eug

eugentics

scientifically wrong and ethically wrong
selective breeding on humans (takes too long and may always be mutations)

genealogy

track genes and trace relatives which reflects phylogeny

population genetics

new alleles arise and spread
population becomes isolated from each other and become a new species over the years
if species are closely related they share alleles

phylogentic systematics *

the field that recontruct evolution history and study pattern among organisms

evolution tree

shows how things evolve over time

homoplasy*

convergent evolution
traits share similarities but have independent evolutionary paths

homology

share common ancestry and have similar traits

T/F: conspiracy theories can be scientific

true, because it is testable unlike supernatural theories m

synonymous mutation

mutation that doesnt change the amino acid sequence

molecular clock *

mutations occur regularly
which can be used to tell time

pseudogenes

genes that have lost their function to encode proteins

QTL

finds high or low levels of lipidstar
target treatment

biogeography *

pattern of distribution and processes
used with phylogeny

vicariance

population is geographically split into two or more isolated groups due to a physical barrier