bsc1005 influenza module 2
How many people were infected by the Spanish flu in 1918?
500 million
Which of these explains one of the processes by which the influenza virus evolves?
A mutation that changes the viral spikes is introduced into the genetic material.
Which of these offers an explanation of the relationship between biology and evolution?
Biology is the study of life, and evolution offers a wealth of information about how life has changed over time.
Which of these choices explains how the process of evolution relates to the study of biology?
Biology is the study of the natural world and the process of evolution is a part of that world.
If you were to create a list to summarize the scientific evidence that supports the idea that populations evolve over time, which of these items would you include?
DNA molecules homologous structures fossils
Which of these is a component of the process of natural selection?
Individuals vary in their traits.
Because individuals vary in their traits, compete for resources, and vary in their fitness, the final component of natural selection results. What is this final step?
Populations become adapted to their environment.
In the quest to produce effective influenza vaccinations, what are the consequences of evolution in the virus?
Sometimes the vaccines are not effective because predictions about the path of the viral evolution don't hold up.
Which statement summarizes the scientific evidence that supports the idea that populations evolve over time?
The idea that populations evolve over time is supported by physical evidence (including fossils, homologous structures, and embryonic development) and chemical evidence (including DNA and protein sequences).
Which best describes the consequences of evolution on producing effective influenza viruses?
The process is more challenging because the virus evolves quickly.
Which of these explains one of the processes by which the influenza virus evolves?
Two different forms of the same virus infect the same host cell and a new virus is created with parts of each form.
Which of the following is a pair of analogous structures?
a butterfly's wing/ a bird's wing
What is a transitional fossil?
a fossil that provides a link between groups of organisms
Which of these can be attributed to the outbreak of the Spanish flu in 1918?
a new variant of the influenza virus
Structures that serve the same purpose but evolved independently are called _____ structures.
analogous
Which method of influenza evolution can be attributed in large part to the efficiency of RNA polymerase?
antigenic drift
homologous
cat foreleg and human forearm dolphin flipper and wing of a bat
The evolution of a species is driven by genetic __________, which can be passed from one generation to the next.
change
Evolution, by its scientific definition, refers to
changes in a species or population over time.
The H1N1 flu outbreak in 2009, to which the human immune system was slow to respond, resulted from
changes in the virus caused by antigenic shift.
The study of homologous and analogous structures, also called ________________ anatomy, studies the similarity of both living and fossilized species' structures to infer evolutionary relationships.
comparative anatomy
Which type of selection favors both extremes, making the most common variant for a trait in a population detrimental?
disruptive selection
The influenza vaccine produced for the 2017-2018 flu season was only 30% effective because of an evolutionary mechanism called antigenic ___________
drift
antigenic ______________ is a mechanism of influenza evolution that causes changes to the spikes on the viral surface.
drift
The scientific definition of ______ refers to changes in a species or population over time.
evolution
Global influenza outbreaks are most likely the effect of
evolution of the virus via antigenic shift.
The forelimbs of modern vertebrates are homologous structures, meaning that they may have changed evolutionarily to perform different functions, but they
evolved from the same body part in a common ancestor.
If a favorable mutation increases the ability of an individual to reproduce then natural selection would
favor this variation.
directional selection
favors an extreme variant for a trait
The process of natural selection
favors some mutations, when they increase fitness.
stabilizing selection
favors the average, or most common variant for a trait
disruptive selection
favors two extremes, selecting against the most common variant for a trait
Reproductive success among individuals with favorable traits, which they pass on to the next generation is often described using the term
fitness
Evolution is the result of
genetic changes within a species or population over time.
Antigenic drift
is the result of the introduction of mutation results in a change to the surface spikes of the influenza virus can be attributed to RNA polymerase inefficiency may make the annual vaccine less effective and cause local outbreaks
Which of these are consequences of antigenic drift as it applies to the influenza virus?
local influenza outbreaks reduced effectiveness of influenza vaccine
The process that drives evolution, and relies on variation in individuals, competition among individuals, differences in individual fitness, and adaptation to the environment, is called
natural
In support of the idea that species change over time, Darwin proposed a four step process called Multiple choice question.
natural selection.
When fossils are arranged and compared according to their age, from __________ to __________ , successive evolutionary change becomes apparent.
oldest youngest
With regards to evolution, fitness is most closely related to successful
reproduction.
antigenic ____________ is a mechanism by which the flu virus may evolve in such a way that slows the ability of the immune system to react, threatening widespread outbreak.
shift
Antigenic drift is a process that occurs when
there are changes on the surface spikes of the influenza virus because of mutations.
Fossils that provide some information about intermediate organisms between groups, like birds and reptiles, are called ______ fossils.
transitional
Antigenic shift is a process that occurs when
two different forms of the influenza virus infect the same host cell, which reproduces elements of both virus to create a new form.
antigenic shift
typically involves animal hosts poses a relatively greater threat a host cell manufactures particles from two forms of the virus delays immune response and may cause an outbreak
analogous
wing of a bat and wing of an insect legs of a spider and legs of a dog