Entrance quizes Flashcards
What does secondary contact refer to?
When populations that have been allopatrically isolated re-establish contact with each other
An species that is an alloployploid is said to have arisen…
via the hybridization between members of 2 different species
Which is the type of reproductive isolation that would prevent species fusion between two groups upon secondary contact, because during their period of allopatric isolation, that males and females in each group evolved to mate at different times of the year?
Temporal isolation
What term best describes a group of closely related species recently descended from a common ancestor?
A species cluster
What kind of selection is thought to have contributed to the sympatric speciation of apple host-form and hawthorn host-form of Rhagoletis pomonella?
disruptive selection
Why does the “ring species” example illustrate the limitations of the Biological Species Concept?
Because although the two populations at the Southern end of the Central valley are reproductively isolated, they are not genetically isolated due to genetic exchange via intermediate groups along the ring
Which of the following is NOT an example of a post-zygotic isolating mechanism?
gametic isolation
The biological species concept is based on what central idea?
That individuals belonging to the same species are reproductively compatible
What type of speciation involves the the complete physical separation of groups (e.g. by a wide river)
allopatric speciation
The death of hybrid offspring as embryos or at an early age is a case of
hybrid inviability
Which of the following is NOT something that would result in balancing selection?
When selection favours individuals with traits of one phenotypic extreme
Alleles represent
Different genes
Which factor(s) contribute to the expression of phenotypic variation within populations?
Both environmental & genetic factors contribute to phenotypic variation
What kind of populations are most likely to experience the effects of genetic drift? What tends to happen when a population experiences genetic drift?
Small populations typically experience greater effects of genetic drift, which is associated with a decrease in genetic polymorphisms
When related individuals mate, what is the likely consequence for their offspring?
Offspring are more likely to be homozygous, and are typically of lower fitness than others.
What do the predictions of the the Hardy-Weinberg equilibrium formula represent?
The frequency of genotypes (and phenotypes) in a population that is not evolving
Which is the least likely effect of a mutation if it is expressed phenotypically on an individual’s fitness?
No effect on fitness
What kind of selection is thought to be responsible for the distribution of human baby weights at birth?
Stabilizing selection
What phenomenon does “founder effect” refer to?
When a population is established from a small subset of an original population, it tends to have less genetic variation than what is found their “parent” population’s gene pool.
What kind of variation exists in two or more discrete states, with intermediate forms often being absent?
Qualitative
Which of the following sentences best describes the relationship between Natural Selection and adaptation?
Natural Selection is an process, Adaptation is a outcome.
What do vestigial structures represent?
parts of the body that were once functional in ancestral species, but are no longer functional in their decendents
What is mean when biologists describe an organism as having high “fitness”?
That the organism posesses traits that makes them well suited to their environment, and as a result is more likely to survive and reproduce than others.
Which of the following areas of study did NOT contribute to Darwin’s major insights about the theory of natural selection.
research on DNA replication
Complete the following sentence:
Selection acts at the level of _____________, and evolutionary change is seen at the ________level.
indivudual
population
How does artificial selection relate to natural selection
Artificial selection works the same way as natural selection, except that with natural selection, human interference, not nature, that makes these decisions.
What is the term for the similarity of indidividuals from different species due to their shared ancestry?
homology
Which of the following was NOT one of Darwin’s observations?
Changes that an organism gains through its lifetime are passed on to its offspring
Which of the following statements is correct?
Question options:
Mutations change genotypes, which may result in changes in the phenotype. Selection acts on the genotype.
Mutations change genotypes, which may result in changes in the phenotype. Selection acts on the phenotype.
Mutations change genotypes, which never results in changes in the phenotype. Selection acts on the phenotype.
Mutations change phenotypes, which always results in changes in the genotype. Selection acts on the genotype.
Mutations change genotypes, which always results in changes in the phenotype. Selection acts on the genotype.
Mutations change genotypes, which may result in changes in the phenotype. Selection acts on the phenotype.
Which of the following most accurately describes what biologists mean when they are talking about “evolution”
Evolution is a change in allele frequencies over time.
What does a polyphyletic group represent?
A grouping that does not include the last common ancestor of all members.
What does it mean if a phylogenetic trees show parsimony?
It represents the simplest hypothesis to account for a given set of observations.
What do homologous traits represent?
Traits inherited from a common ancestor.
What is the use of an outgroup when constructing a phylogenetic tree?
It helps resolve which traits are ancestral or derived
What is a key assumption when estimating how recently two groups shared a common ancestor based on overall genetic similarity using a molecular clock?
That the rate of mutation is constant.
On a phylogenetic tree, a node represents ______, while the tips of the branches represents __________
the point at which lineages diverge ; species
What are the two main goals of systematists?
to study the diversity of life and identify its evolutionary relationships
Why are synaptomorphies so useful for cladistic analysis
as they are shared derived characters and can serve as markers for monophyletic lineages
Which of the following lists traditional heirarchial levels of classification in order of increased inclusivity
species, genus, family, order, class, phylum, kingdom, domain
BONUS: In the phylogeny depicted below, which group(s) is/are most CLOSELY related to the frogs?
The dog and the human are equally closely related to the frog, while the lizard is less closely related
Lizards and mammals evolved from a common ancestor
What is the site of primary growth in plants?
In the apical meristems
What is the term that refers to the ability of almost any cell within a plant to give rise to other parts of a plant?
Totipotency
What is the name given to a root that arises in an unsual location?
Adventitious root
Which of the primary meristems gives rise to the primary xylem & primary phloem?
Procambrium
What makes up the majority of a plant cell’s primary cell wall?
Cellulose
Which of the following traits is seen in Monocot angiosperms?
Vascular bundles distributed throughout the ground tissue
Which of the following is NOT one of the tissues of the Ground Tissue System?
Periderm
The term “poikiohydric” refers to plants that
.have little control over their water content, and do not restrict their water loss
What are the names of the two major groups of angiosperms?
The monocots & the dicots
What is the major adaptive importance of the evolution of pollen to the success of the gymnosperms & the angiosperms?
There is no longer a need for liquid water for reproduction
Which of the following is NOT a “Bryophyte”?
Horsetails
Which group of land plants has the greatest number of living species?
angiosperms
What is the primary role of land plant vascular tissue?
Transportation
What is the “defining” feature of the angiosperms?
Flowers
Which of the following traits is NOT found in seedless vascular plants?
pollen
Which of the following groups is thought to have given rise to the ancestor of the land plants?
green algae
In the land plant’s “alternation of generations”, which of the following best describes the “sporophyte”?
Multicelluar, diploid, produces spores via meiosis
What is the typical composition of the “A” horizon layer in soil?
Mixture of sand, silt or clay
Phloem transport carbohydrates from ________ which are they are ________ to ______ where they _________.
sources; abundant; sinks; are needed;
What is the driving force for water movement through the xylem?
Transpiration in the leaves
What is a epiphyte?
A plant that grows on an another plant
What is the name of the pathway in which water travels across the root to the xylem only through the cytoplasm of plant cells
The symplastic pathway
What is the name of the process by which NH4+ (ammonia) is produced from atomospheric nitrogen?
Nitrogen Fixation
What is the number of essential elements needed by plants that are called macronutrients?
9
When molecules move via active transportation there is a net movement from areas of ______ to _______ concentration, which ____ require expending energy
low, high, does
Which of the following is not one of the three major elements that make up 96% of the plant dry weight
phosphorus
What is the name of the name of the water-conducting channel proteins that span the plant cell’s plasma membrane?
aquaporins
What happens during imbibition?
Water enters the seed and leads to germination
What does the egg sac represent?
The female gametophyte
What is the correct order of whorl organization from the outside to the inside of a “perfect” flower?
Sepal -> Petal -> Stamen -> Carpel
How do aggregate fruits develop?
They develop from several ovaries in a single flower
Apomixis refers to:
when a diploid embryo can form from a unfertilized egg
Which TWO “whorls” in a flower contain the non-reproductive parts?
The Petals & The Sepal
Which characteristics best describe the gametophyte?
haploid, multicellular, grows from a spore
How many full sets of chromosomes does a sterotypical endosperm contain in an angiosperm?
Three
Apical dominance is characterized by the ________ by ________ produced in the __________.
suppression of growth of axillary buds
auxin
tips of the stems
How do plant shoots grow in relation to the direction of light?
Plant shoots grow towards a light source: a response called phototropism
Which type of plant movement is described as non-directional?
Nastic movement
Cytokinins are synthesized mainly in _________, and cause _________.
the root tips cell division
What is the name of the plant’s response to a pathogen that involves selectively killing off parts of its body to protect the rest of the plant?
Hypersensitive response
One of the effects of ______ is an elongation of inter-node distances, in a phenomenon called _________.
gibberellin bolting
Which of the five major groups of plant hormones is typically expressed in a gaseous form?
Ethylene
Where does primary growth of stems occur?
In the shoot apical meristems, at the tip of the stems
Which plant hormone is primarily responsible for the phototrophic response of plants?
Auxin
What do demographers call a group of individuals born at the same time and whose fate is tracked over time?
a cohort
What does a population refer to?
A group of individuals of the same species located in the same place at the same time
What type of survivorship curve is characterized by a fairly low survivorship early in life, with dramatically lower mortality as the cohort ages
TYPE 1
in a population that undergoes exponential growth
the organisms get larger with each generation
What does carrying capacity represent?
The maximum number of individuals of one species that a habitat will support
A populations’ geographic range refers to…
…the overall space in which it lives
In the equation describing exponential growth,
Nt=N1(1+r)^t
what does the “t” represent?
the amount of time that elapsed
What is the names for the type of dispersion pattern arises when individuals of the same species associate together in social groups?
Clustered
A species’ whose effect other members of the community is disproportionate to their abundance or biomass is called a…
keystone species
Who proposed the theory of island biogeography?
MacArthur & Wilson
The similarity of some aspects of the niches in closely related species is most likely due to…
Divergent selection acting on their common ancestor
A interspecific interaction in which both species benefit from their interactions is one that is…
mutualistic
What does interspecific competition represent?
Question options:
Competition between members of different species for limited resources
What is the difference between the fundamental niche and the realized niche?
The fundamental niche represents the full range of climate conditions and food resources that permit the individuals in a species to live. The realized niche is the actual range of habitats occupied by a species. The fundamental niche is always bigger than (or equal to) the size of the realized niche.
