Module 1 Flashcards
What is life capable of?
Growth, Reproduction, Functional activity, Adaptation
What is a prion?
Infectious agent that causes proteins to fold up in weird ways, NOT alive
What are viruses?
Infectious agents that use host machinery, yet they don’t respond to stimuli, NOT alive
What are kingdoms?
Taxonomic category of the highest rank
What are the 6 kingdoms?
Plants, animals, fungi, Protista, bacteria, archaea
What are the 3 domains?
Eukarya, Bacteria, Archaea
What is a species?
A group of individuals that regurlarily breed together
What are prokarya?
Single cells that lack membrane-bound organelles
What are eukarya?
Organisms whose cells have a nucleus enclosed within membranes
How do prokaryote get to eukaryote?
- Acquire a nucleus
- Acquire a mitochondria
- Acquire chloroplasts
What is evolution?
Change in inherited characteristics of biological populations over successive generations
What is natural selection?
Non-random evolution, phenotypic variation that is heritable
What is selection acting upon?
Phenotypes
What is adaptation?
Traits that are evolved through natural selection
What is stabilizing selection?
Pushing everything toward the middle/mean, extreme variants are selected against
ex: birth weight
What is directional selection?
Selection will move in directional of favourable phenotype based on its survival in the given environment
ex: different fur colours
What is sexual selection?
Features of an animal whose function is not to improve survival but to maximize their reproductive success
What is intrasexual selection?
Individuals intimidate, deter, or defeat same-sex rivals
What is intersexual selection?
Individuals make themselves more attractive to the opposite sex
The flashy sex has greater:
Variance or skew, will evolve more elaborate traits
The choosy sex has greater:
Investment, therefore they are more selective about who to mate with
What is skew?
Tells us about the shape of distribution
What is the Bateman’s Gradient?
The idea that whichever sex has greater variance or reproductive skew (flashy) will have a steeper Bateman’s Gradient
What is Sexy Sons/Fisher’s Runaway Selection Model?
The idea that females show a preference for a particular character, so the sons of those females will display that character and the daughters will display that preference
What is the Good Genes/Immunocompetence hypothesis?
The idea that some males are genetically more resistant to infections/parasites, therefore they would survive longer be less likely to affect females and their offspring
What is the Pre-existing sensory bias and sensory exploitation?
The idea that females have a bias for particular types of sensory stimuli, and they mate with males that produce their preferred signal
What is a phylogeny?
A history of organismal lineages as they change through time
What is a parsimony?
How to get to the pattern of trait expression in the descendants with the fewest changes
What is a pleiotropy?
When a single gene influences many phenotypic traits
What is genetic drift?
A change in frequency of an existing gene (random)
What is genetic bottleneck?
An extreme example of drift where an event results in a big decrease in population size and genetic diversity
What is founder effect?
Similar to a genetic bottleneck except here a subset of the population “founds” a new population somewhere else (still results as a decrease in population size and genetic diversity)
What is inbreeding?
When closely related individuals mate
What do natural barriers do?
Separate species and prevent gene flow between populations
What is speciation?
Occurs when gene pools are separated and populations diverge genetically overtime
What is reproductive isolation?
Mechanisms that prevent gene flow between members of different species
What is a zygote?
Cell formed by the joining of two gametes
What are pre-zygotic isolation mechanisms?
They prevent the formation of a zygote
What is ecological isolation?
Different environments
What is temporal isolation?
Mating behaviour at different times
What is behavioural isolation?
Different mating activities
What is mechanical isolation?
Mating organs are incompatible
What is gametic isolation?
Gametes cannot unite
What are post-zygotic isolation mechanisms?
Occur after the formation of a zygote
What is allopatric speciation?
When there is physical isolation (ex: on an island)
What is sympatric speciation?
When species arise in the absence of some sort of physical isolation/barrier
What is parapatric speciation?
When species live close to each other and only share a small contact zone (ex: Californian salamanders)
What are chromosomes?
Genetic material (DNA) in all cells
What are epigenetics?
Heritable changes depending on the environment that doesn’t require changes to the DNA sequence (mutation)
What is symbiosis?
Relationships that evolve between individuals
What is parasitism?
A relationship between individuals where one individual benefits (parasite) to harm the other (host)
What is commensalism?
A relationship between individuals where one individual benefits and the other is unaffected
What is mutualism?
A relationship between individuals (usually from different species) where both individuals benefit
What is a microbiome?
Totality of microbes in an environment
Where do bacteria come from?
Babies get bacteria in utero, continue to gain over the first few years, then the gut can be repopulated by the appendix
What problems have arisen from urbanization?
Unfamiliar bacteria, bacteria in the wrong places
What are resistant bacteria?
Bacteria that have genes that allow them to survive from in the presence of an antibiotic
How do bacteria become resistant to antibiotics?
Some individuals have mutations that protect them against antibiotics. Those bacteria with mutations that make them highly resistant with survive after selection pressure and reproduce. The frequency of the alleles for resistance will be higher in the next generation
What are the 3 classes of antibiotics?
Those who interfere with the:
- Cell wall
- Synthesis of nucleic acids
- Synthesis of proteins
What types of adaptation make bacteria antibiotic resistant?
- Drug modification (alters antibiotics so they don’t work)
- Drug degradation (bacteria break down antibiotics)
- Reduced drug accumulation within bacteria (prevent antibiotics from entering)
What are the two ways bacteria store DNA?
Chromosomal and plasmid
What is horizontal gene transfer?
Plasmids are copied and transferred
What are two problems with drug development?
- The more that we use an antibiotic to treat infection, the faster it will become ineffective
- Not cost effective to create antibiotics
What are probiotics?
An attempt to re-establish or increase populations of “good” bacteria
What are the 5 types of virus/bacteria transmission?
Droplet, airborne, waterborne, vector, sit-and-wait
What is virulence?
How much the virus/bacteria affects the host’s fitness
What is an epidemic?
New cases of a disease that exceed expectation based on recent experience
What is a pandemic?
An epidemic that has spread through a large region
What makes viruses so adaptable?
Relatively simple construction, short generation time, high mutation rates
What are the subtypes of influenza?
Hemagglutinin (important for binding and selectivity) and Neuraminidase (lets new copies of the virus out of the cell so they can affect other cells)
What is antigenic drift?
Small changes in the virus that occur gradually through the accumulation of mutations
What is antigenic shift?
Large, abrupt changes to the virus due to the cell being infected by multiple viruses (ex: viruses from more than one species H1N1)
Why was there such worry around the H1N1 virus?
- The immune system will be unable to recognize them
- Humans will not have immunity from viruses from another species
- Shifted viruses have potential for high virulence
Why was the Spanish flu considered strange?
- There were 3 waves of infection
- Healthy, young adults were being lethally affected
- Effects of the virus were really rapid
What is ebola/Marburg hemorrhagic fever?
Filoviruses or filamentous viruses that can affect humans as well as other primates
How do you deal with pandemics?
Quickly produce a vaccine, limit exposure and transmission, do a bottom-up approach to finding a possibly pandemic virus
When faced with selection pressure, species can:
- Show phenotypic plasticity
- Evolve or adapt
- Go extinct
What is phenotypic plasticity?
Some organisms can alter the phenotype, express different traits depending on environmental condition (does not require genetic change or evolution)
What is trophic mismatch?
Timing of migration and breeding need to coordinate with the timing of food availability
What is the Lombard effect?
We will increase the amplitude (loudness) and frequency (pitch) of our speech when ambient noise increases
What are alleles?
Different versions of the same gene
What is hybrid inviability?
Gametes unite but viable offspring cannot form
What is hybrid infertility?
Viable hybrid offspring cannot reproduce
What is genetic drift?
A change in allele frequency that occurs due to chance
What is the scientific method?
- Make observations
- Form a question
- Propose a hypothesis
- Test the hypothesis
- Assess, reject, or accept hypothesis
What is internal validity?
Was the study well designed to test the cause and effect relationship between the variables?
What is external validity?
How well can your findings be generalized to the population outside of you study?
What is statistical significance?
Refers to results that are not attributable to chance (depends on size of sample and size of observed effect)
Why do statistics matter?
The mean tells you the middle, and the standard deviation or skew tells us about the shape of the distribution. Knowing this helps us know whether two means are likely to be the same of different
What was Lamark’s assumption?
Thought that there was use-dependent change (e.g. giraffes’ stretch their necks over generations because they were stretching to reach different branches
What is inbreeding depression?
The reduced biological fitness in a given population as a result of breeding with related individuals
What is transmissibility?
mode of transmission → how efficiently is it passed from one host to another
What is the Lombard effect?
The involuntary tendency of speakers to increase their vocal effort when speaking in loud noise to enhance the audibility of their voice
