BIOL 1200 Exam 1 Study Guide
Scientific method (Chap 1)
∙ Deductive reasoning starts out with a general
statement, or hypothesis, and examines the
possibilities to reach a specific, logical conclusion.
∙ Inductive reasoning is the opposite of deductive,
inductive reasoning makes broad generalizations
from specific observations. You make many
observations, discern a pattern, make a
generalization, an infer an explanation or a theory. We also discuss several other topics like When does the anarchist wave happen?
∙ A theory is an assumption based on limited
information or knowledge; conjecture.
∙ A hypothesis is a testable explanation for a set of
observations based on available data.
∙ In terms of science, theories are explanations for
natural phenomena that have been repeatedly tested
and, as a result, exceptionally well supported by
∙ Make observations
∙ Formulate a hypothesis
∙ Devise a testable prediction
∙ Conduct a critical experiment
∙ Draw conclusions
o The scientific method tells us when we should
change our minds. It was used to provide If you want to learn more check out What are scatterplots?
support for the cell theory, Lewis Pasteur’s
experimental test of spontaneous generation.
Introduction to Evolution and Natural Selection (Chap 19) ∙ Typological Theories Concept- Every species was a perfect type and, therefore, unchanging We also discuss several other topics like What is the difference between morbidity and mortality as it relates to disease?
We also discuss several other topics like Which philosophic view sees human beings as machines which can be understood as a collection of their individual parts?
∙ Scala Nature- Although species are “fixed”, they had an organization sequence from small and simple If you want to learn more check out What is the difference between civil right and civil liberty?
(bottom of the ladder) to large and complex (top of
∙ Evolution did NOT occur according to Greek
Philosophers. Swedish musician/botanist Carlos
Linnaeus (1707-1778) “for the greater glory of god”
develop the two-part, binomial format of naming species
∙ Georges Cuvier- Sometimes referred to as the father of Paleontology, documented fossil animals unlike any living species; he concluded that they had gone extinct
∙ Charles Lyell- The leading geologist during Darwin’s time, he incorporated Hutton’s thinking (that earth’s geologic features could be explained by gradual mechanisms, such as valleys being formed by rivers wearing through the rocks) into his proposal that the same geologic processes are operating today as in the past, at the same rate. We also discuss several other topics like Who wrote "studies in the psychology of sex"?
∙ Jean Baptiste Lamarck- he proposed a mechanism for how life changes overtime. He proposed species change over time through the inheritance of traits acquired from use or disuse. The idea was that if a species uses that part of the body it becomes larger and stronger. If it is not used it will deteriorate.
∙ Thomas Malthus- he contended that much of human suffering—disease, famine, and war—was resulted from the human populations potential to increase faster than food supplies and other resources. “The power of the human population is infinitely greater than the power on the earth to produce subsistence for man. Populations grow geometrically but their food supply grow arithmetically.
∙ Alfred Russel Wallace- A British naturalist working in the South Pacific islands of the Malay
Archipelago. Wallace developed a hypothesis of natural selection nearly identical to Darwin’s.
∙ It was developed by Jean Baptiste Lamarck, it stated that an organism can pass these
modifications to its offspring
∙ Malthus wrote “Essay on the Principle of Population” (1798), which Darwin read and was inspired by. The central theme of Malthus’ work was that population growth would always overpower food supply growth, creating perpetual states of hunger, disease, and struggle. Population growth
grows at an exponential rate while food supplies grow at an arithmetic growth
∙ Geometric Progression- When things increase by a nonfluctuating factor (ex. 2,4,8,16,32,64) the factor here is 2
∙ Arithmetic progression- When things increase by a constant number (2,4,6,8,10,12,14,16,18,20) here is a constant +2
∙ Fossils give us insight into how prehistoric plants and animals obtained food, reproduced and even how they behaved. At times fossils can also provide evidence for how or why the fossil organism died. Fossils aren’t only used to understand individual organisms. Geologists also use fossils for what’s called biostratigraphic correlation, which allows researchers to match layers of rock in different locations by age based on how similar the fossils in each rock layer are. This information can be used to help understand when different layers of rock were formed even when large distances separated them.
∙ Fossils or organisms that show the intermediate states between an ancestral form and that of its descendants. (the hind limbs of whales)
∙ A remnant of a trait that is used to exit in an organism’s ancestors. The present organism carries some form of this trait but no longer serves a purpose in the present. An example is some snakes retain vestiges of the pelvis and leg bones of walking ancestors, the coccyx, or the tailbone in humans.
∙ Phylogeny- the evolutionary history of a species or a group of species
∙ Homology- similarity in characteristics resulting from a shared ancestry
∙ Developmental Homology- it is recognized in embryos. Two different organisms can have a common embryonic trait, say gill pouches or a tail, but in some of those organisms those gills or tails are lost. Gills pouches or tails are vestigial traits in humans, cats, chickens, etc. These organisms share genetic homologies, but are structurally different.
∙ Structural Homology- an example of an organ or a bone that appears in different animals, underlying anatomical commonalities demonstrating descent from common ancestor. In other words, it’s when very different animals have bones that appear very similar in form or function and seem to be related.
∙ Evolution- A change in the frequency of alleles in a gene pool in a given population over time, evolutionary change takes place in populations. “Evolution is NOT progressive”. The pattern of evolution= Descent with modification
∙ Adaption- An inherited characteristic of an organism that enhances its survival and reproduction in a specific environment.
∙ Natural selection- the result of natural factors, which favor certain variations
∙ Artificial Selection- The deliberate selection of certain traits (by humans), for example, a poodle is the result of artificial selection
∙ Population Variation
∙ Variation is heritable
∙ More offspring produced than can survive ∙ Survival and reproduction are nonrandom
∙ Natural selection sorts existing variants; it does NOT create new traits or change existing traits in individuals. It is the process by which individuals with certain heritable traits produce more surviving offspring than individuals lacking those traits. Natural selection acts on individuals.
∙ Antibiotic resistance evolves naturally via natural selection through random mutation, but it could also be engineered by applying an evolutionary stress on a population. Once such a gene is generated, bacteria can the transfer the genetic information in a horizontal fashion (between individuals) by plasmid exchange. The agent of selection is natural selection
∙ The idea of descent is that similar organisms came from one prehistoric/ancient organism. This common
ancestor encompasses the idea of the unity of life.
But with this came adaption and evolution, species
began to differentiate based on their environment
and need to survive. This created diversity as
organisms developed modifications to the original
o Darwin published the origin of species in 1859
Genetic terminology review
∙ Allele- any of the alternative versions of a gene that may produce distinguishable polygenic effects
∙ Gene- A discrete unit of heredity information
consisting of specific nucleotide sequences in DNA
(RNA in viruses)
∙ Homozygous- having 2 identical alleles for a given gene
∙ Heterozygous- having 2 different alleles for a given gene
∙ Codominance- the situation in which the phenotypes of both alleles are exhibited in the heterozygote
because both alleles effect the phenotype in
separate , distinguishable ways
∙ Replication- the process of duplicating or producing an exact copy of a polynucleotide strand such as
∙ Transcription- the synthesis of RNA using a DNA
∙ Translation- The synthesis of a polypeptide using the genetic information encoded in an mRNA molecule;
a change from nucleotides to amino acids
∙ Proofreading- used in genetics to refer to the error correcting processes. DNA POLYMERASE is an
enzyme the elongation for new DNA (for example at
a replication fork) by addition of the nucleotides at
the 3’ end. It is the DNA proofreader
∙ Point mutation- a change in a singular nucleotide
pair of a gene
∙ Silent mutations- has no observable effect on the
∙ Missense mutations- changes the amino acid
∙ Nonsense mutations- codes for a stop codon
Evolution of populations (Chap 21)
∙ Evolutionary change below the species level; change in the allele frequencies in a population over
∙ Mutation- a change in the nucleotides sequence of an organism’s DNA
∙ Gene duplication- due to errors in meiosis
∙ Rapid sexual reproduction- includes crossing over, independent assortment of homologous
chromosomes, and fertilization
∙ All of the copies of every type of allele at every locus in all the members of the population
∙ The Hardy Weinberg principal states that allele and genotypic frequencies in a population will remain
constant from generation to generation in the
absence of other evolutionary influences.
∙ No, Hardy and Weinberg did not work as a team.
Weinberg developed develop the principle of genetic
equilibrium independently of British mathematician
G.H. Hardy about 6 months before Hardy’s paper
was published in English. His lecture was printed
later that year in the societies yearbook.
∙ No mutations
∙ Random mating
∙ No Natural selection
∙ Extremely large population size
∙ No gene flow
∙ When mating is random in a large population with no disruptive circumstances, the law predicts that
both genotype and allele frequencies will remain
constant because they are in equilibrium.
∙ The H-W equilibrium can be used as a null hypothesis, compared to values from a real population, to describe statistically significant deviations from the Equilibrium. If the deviation is significant, then the gene frequencies are changing and thus, evolution is occurring.
∙ 1 generation
∙ They remain constant
∙ By using the H-W equation and looking at the expected and observed frequencies.
∙ Natural selection, mutation, gene flow, or genetic drift
∙ Mutation can be spontaneous and completely creates new variation
∙ The contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals
∙ Directional Selection- natural selection in which individuals at one end of the phenotypic range survive and reproduce more successfully than other individuals do
∙ Stabilizing selection- natural selection in which the intermediate phenotypes survive or reproduce more than extreme phenotypes
∙ Disruptive Selection- natural selection in which indivuals on both extremes of a phenotypic range survive and reproduce more successfully than do individuals with intermediate phenotypes
∙ A process which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next.
∙ Regarding to fitness, it can cause a decrease in fitness because it is not selective and better fit organisms can die out.
∙ The effect of founder effect and bottle neck are pretty much the same genetically, but the way they happen are where they differ. In founder effect and few alleles migrate, in bottleneck a large population of alleles die.
∙ The loss of an allele in when one is completely gone. When the allelic frequency in a population reaches 1.0, the allele is the only one left in the population, and it becomes fixed for that allele. The other allele is permanently lost. The loss of an allele can happen in something such as the bottleneck, if a forest fire happens and one allele is killed off, it is gone.
∙ The transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes