BIO 112 Final

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Evaluate the phrase "descent with modification"

"Descent with Modification" is the idea that 1. Species change throughout time, and 2. Species are related by a common ancestor. Transitional elements that were looked at over the course of a million years from aquatic to tetrapod. They have the same blueprint and same bones in that order, but they're slightly different. So, you can see that they're descendents of each other but they've been differentiated.

List the ways at which gene expression can be affected in eukaryotes.

(Look on Day 1 Slide). Differential gene expression activators turn on transcription for specific genes, but if something were to happen to those activators then certain genes would turn off or on.

Describe the contribution of energy from live and dead material in aquatic and terrestrial habitats

(MOST) Producer → Primary Consumer → Secondary Consumer → Top predator or Tertiary Consumer (LEAST). Decomposers get energy from dead organisms and their fecal matter. /// Two trophic chains: decomposers & consumers. The base level of vegetation determines base level of energy, but also the ability of the decomposers to decompose detritus or dead material. We rely on efficient decomposers to break organic matter to its components, so that vegetation can grow from the nutrients.

Biomass & Productivity in different Biomes

(Productivity / Biomass) Arctic Tundra VERY LOW / VERY LOW Boreal Forest LOW, BUT HIGHER THAN ARCTIC TUNDRA / HIGH Temperate Forest LESS THAN RAINFOREST BUT MORE THAN DESERT AND GRASSLAND / MODERATE Temperate Grassland LOWER THAN FOREST / LOW (when it's warm it's also rainy - similar for temperate forest) Subtropical Desert VERY LOW / VERY LOW Tropical Wet Forest VERY HIGH / VERY HIGH

Evaluate a scenario to determine which evolutionary process (for list, see Table 23.4) is acting

(look back at the question about mechanisms for evolution) // see which selection is happening based on a graph - what do you expect to happen with trait value during specific events?

Evaluate the effect of the different evolutionary processes on genetic variation and fitness

(was answered in a previous question about different types of natural selection and mechanisms for evolution) ///Say what happens to average trait value. Directional Selection - either high trait value or low one is preferred, all others will die out, genetic diversity decreases and eventually trait value changes. Stabilizing selection - average trait value is the best one, and low/high trait value dies off - genetic diversity decreases and average trait value doesn't change. Disruptive selection - most individuals with average die out, and low/high survive - genetic diversity is maintained or increases slightly, and average trait value remains the same.

Describe the different zones of a lake and ocean

*Photic Zone: all regions with enough sunlight for photosynthesis *Aphotic Zone: regions without sunlight underneath photic zone *Benthic Zone: Bottom of the ocean where plankton and detritus feeders are found Oceanic Zone: "open ocean" Neritic Zone: Very productive area, shallow and between intertidal zone and photic zone (ex: coral reef) Intertidal Zone: Beach that is exposed to air at low tide, and submerged at high tide. Littoral Zone: the shore of a lake, shallow, and flowering plants are rooted Limnetic Zone: just offshore of the lake, also where photic zone is *= shared by both oceans and lakes

Describe the 2 types of coeloms and what they accomplish

1. Acoelomates: have no body cavity and all germ layers are next to each other 2. Coelomates: have a true fluid-filled body cavity enclosed in the mesoderm itself. Humans are coelomates because the coeloms separate body cavities & aids in O2 / nutrient circulation. It can be used for a hydrostatic skeleton. 3. Pseudocoelomates: has a body-fluid cavity between mesoderm and endoderm, it would be used for a hydrostatic skeleton

Define the three major species concepts

1. Biological Species Concepts: populations or species are evolutionary independent if reproductively isolated 1a. Prezygotic Isolation: prevented from mating, gametes not interacting - Temporal: different time release of gametes - Habitat: geographic barrier or preferred different habitats - Behavioral: mates aren't recognized - Gametic behavior: egg and sperm are incompatible - Mechanical: reproductive organs are incompatible 1b. Postzygotic Isolation: hybrid offspring have low fitness - Hybrid viability: offspring don't develop normally and die - Hybrid sterility: offspring matures, but it's sterile and can't reproduce Disadvantages → fossils & asexual reproduction 2. Morphospecies Concept: ID independent lineages by difference in morphological features (relationship between living organisms and their bodily structures). Unique features arise if populations are independent Disadvantages → Can't ID cryptic species (non-morphological traits), subjective 3. Phylogenetic Concept: based on reconstructing evolutionary history of populations. ID'd by synapomorphies (homologous traits inherited from common ancestor) - Monophyletic group (clade): ancestral population and all descendents - Species: smallest monophyletic group on the tree of life - Synapomorphy: trait unique to monophyletic group, becomes distinct → makes new lineage dissimilar enough to be new species Advantages → applies to any population, synapomorphy differ only if no gene flow

Describe the different types of asexual reproduction in animals

1. Budding in Hydra: offspring forms within or on a parent then breaks free - "mini me" 2. Fission in Anemones: individual gets bigger than splits down the middle 3. Parthenogenesis in Lizards: female offspring develops from unfertilized diploid egg identical to mother - no males exist - "virgin origin"

Describe types of modified stems and their functions

1. Cactus stems store water 2. Stolons produce individual nodes above the ground (stems run over soil surface) 3. Rhizomes produce nodes horizontally below ground (they grow horizontally) 4. Tubers are a form of rhizomes that store carbohydrates, they're used by plants to survive winter or dry months because they provide energy and nutrients 5. Thorns provide protection from herbivores

Describe the 5 fundamental actions that cells perform at different points during development

1. Cell Proliferation: (division) mitosis & cell checkpoints 2. Apoptosis: programmed cell death to add shape & sculpt 3. Cell Movement or Differential Expansion (Plants): cells move relative to each other or away from each other. Plants cannot do this, instead they have differential expansion (expanding the cell instead of moving) 4. Cell Differentiation via Differential Gene Expression: going through a cascade that makes activators for activating other activators that help form the organism 5. Cell-Cell Interactions: signal and receptors tell neighboring cells what to do

Describe the stages of embryonic development in animals and the result of each stage

1. Cleavage is the first step in embryogenesis: cells rapidly divide just after fertilization, and the cytoplasmic determinant partitions along with the cell without increasing its growth. The embryo continually divides to form a blastula (with the small partitioned cells called blastomeres). The cytoplasmic determinant is distributed unevenly amongst the blastomeres. This results in cell differentiation because the master regulator (in fruit flies, it's bicoid) is distributing different regulatory transcription factors that initiate gene transcription for specific genes. 2. Cleavage occurs over a week in the oviduct (from the ovary to uterus). Eventually the embryo plants itself in the uterus, if the embryo never leaves the oviduct it results in an ectopic pregnancy. During this stage, the embryo becomes known as the blastocyst - inside the blastocyst is the trophoblast and the inner cell mass. The trophoblast will become the placenta, and the inner cell mass will become the actual embryo. 3. During cell movement, gastrulation is taking place the three primary germ layers begin to develop: ectoderm, mesoderm, and endoderm. The ectoderm will form the nervous system and the skin. The mesoderm forms the skeletal, muscular, cardiac, reproductive, and excretory systems. The endoderm forms the digestive tract and creates the liver, pancreas, thyroid, parathyroid, and thymus. 4. During organogenesis, a temporary structure called the notochord forms in the mesoderm and signals other structures to develop. In particular, the notochord signals a portion of the ectoderm to fold in order to become a neural tube for the nervous system. Eventually a series of other cell movements in animals results in the formation of organs into eventually a continually developing organism.

Describe the difference between diploblasty and triploblasty

1. Diploblasty: 2 germ layers (endoderm and ectoderm) 2. Triploblasty: 3 germ layers (endoderm, mesoderm, ectoderm)

Evaluate how the different types of natural selection impact the average value of a trait and the genetic variation

1. Directional Selection results in the mean of the bell curve moving either left or right to account for whether the particular trait is a lower or higher fitness 2. Stabilizing Selection decreases genetic diversity, thus causing the bell curve to become skinnier 3. Disruptive Selection turns a normal distribution curve to a bimodal distribution, no change in the mean

Analyze a trait and determine what type of selection it is undergoing

1. Directional Selection: this changes the average value of a trait on normal distribution graph, so the mean moves from lower to higher fitness (this is because one trait is being selected out more and more so the entire population eventually averages to have more of that trait be higher fitness) 2. Stabilizing Selection: those with intermediate traits are selected = no change in average trait value, but genetic variation is reduced 3. Disruptive Selection: extreme phenotypes are favored, average trait stays the same, increased/similar genetic diversity, can result in speciation

Identify what parts of the body come from which germ layer

1. Endoderm - forms directly from gastrulation. Forms respiration, urinary, digestive track, and various other organs 2. Mesoderm - forms skeletal system, muscular system, circulatory cells, and different organs 3. Ectoderm - forms skin & nervous system (notochord)

Analyze mutants to determine which of the segmentation genes is responsible for that mutant

1. Gap genes: define the general position of head, thorax, and abdomen 2. Pair-Rule genes: demarcate the edges of individual segments 3. Segment Polarity genes: establish anterior - posterior boundaries in individual segments

Describe the three types of homology

1. Genetic Homology: similarity of DNA sequences to different species; example: fruit fly & human have similarity for gene eye formation and 90% of each genome is identical. 2. Development Homology: in embryos of different species with common ancestor; example: humans, cats, chicks have gill pouches and tails even though some lose these features. 3. Structural Homology: similarity in adult morphology; example: same bones in the same relative position despite being different animals.

Identify the characteristics that define all Animals

1. Multicellular with Extracellular Matrix 2. Heterotrophs 3. Move under own power (but can be sessile, though have moved at some point) 4. Have neurons (except sponge) 5. Muscle cells that contract to change body shape (except sponge)

Describe the four mechanisms which can cause evolution

1. Natural Selection: increased frequency of alleles = reproductive success 2. Genetic Drift: allele frequency changes RANDOMLY 3. Gene Flow: individuals leave a population to join a different one, and breed with them. 4. Mutation: modified allele frequencies

List the 4-step process (pattern formation, morphogenesis, determination, differentiation) of cellular differentiation and the role of each step

1. Pattern formation is similar to morphogenesis. Pattern formation is the axes developing. The formation of the segmentation genes (pair-rule, gap, segment polarity) helps give the organism a shape. 2. Gap genes create head, thorax, and abdomen - if this wasn't here then there wouldn't be segments. The earlier the mutation the more severe the mutation consequences. 3. Pair-rule genes create anterior-posterior boundaries within each segment, and make multiple bands through the middle segment. Each segment made in the middle is different than the other (like the vertebrae in the spinal column, they all are different with different roles). 4. Segment polarity genes give polarity to each segment. So each band will have an indication of whether it's anterior or posterior. If this gene was mutated then a band would have both posterior or anterior of a band, but it wouldn't affect an entire head region. You may end up with accurate structure of the band but slightly further from where it was supposed to be. An activator is made for the hox genes, but the hox structure may be slightly shifted. 5. Determination is when a cell commits to a development path (ex: mesoderm cells are part of mesoderm tissue but have not been determined as skeletal or cardiac). During differentiation, when the cell starts making its characteristic genes (hox through activators turned on).

Evaluate the prezygotic and postzygotic isolating mechanisms for the biological species concepts

1. Prezygotic Isolation: prevented from mating, gametes not interacting - Temporal: different time release of gametes - Habitat: geographic barrier or preferred different habitats - Behavioral: mates aren't recognized - Gametic behavior: egg and sperm are incompatible - Mechanical: reproductive organs are incompatible 2. Postzygotic Isolation: hybrid offspring have low fitness - Hybrid viability: offspring don't develop normally and die - Hybrid sterility: offspring matures, but it's sterile and can't reproduce

Describe the difference between radial and bilateral symmetry

1. Radial Symmetry: having 2+ planes of symmetry 2. Bilateral Symmetry: having 1 plane of symmetry, long & narrow bodies

Describe the 4 tenets of natural selection (Darwin's 4 postulates)

1. Variation existed in population 2. Variation was heritable 3. Variation in reproductive success (survival of the fittest) 4. Selection has occurred. (Vestigial structures and transitional features act as evidence for the postulates and evolution proof)

Explain the difference between fundamental and realized niche

A Fundamental niche is the resources/conditions tolerated without competition. A Realized niche is the portion of resources/conditions used with competition present (typically less than fundamental niche because competition decreases the range of resources used. If there's no competition overlap in niches, and there's a stronger species, the weaker species will move their curve in the direction of the arrow towards the realized niche because they cannot compete anymore. So they occupy where the realized niche line is and onwards (because that's the end of the stronger species range for resources). // Fundamental is the niche that the species would prefer and inhabit if the competition species wasn't present - it's their most preferred niche. However, if there is a stronger competitor, then natural selection will favor individuals in the realized niche since it does not overlap with competitors. The strong competitor remains the same.

Describe metapopulation

A metapopulation consists of a group of spatially separated populations of the same species which interact at the same level.

List the steps that link a change in the base sequence of a gene to a change in the phenotype of an organism

A mutation in a base sequence can lead to an addition, removal, or substitution of any sequence. There can be a mutation at any point during transcription or translation. This will affect what that codon eventually becomes when it's translated as an amino acid from mRNA. Then the function of that amino acid will be different than its initial intention.

Define what a population is vs. a community.

A population is a group of the SAME species living in the same area at the same time sharing a common gene pool. A community is the populations of animals that live in a specific region under certain environmental conditions.

Describe a population and population ecology

A population is all the organisms of the same group or species who live in a particular geographic area and are capable of interbreeding. Population ecology is the study of populations in relation to the environment including environmental influences on density, distribution, age, structure, and population size.

Evaluate if a population is in Hardy Weinberg equilibrium

A population is in Hardy Weinberg equilibrium when the observed genotype frequency is within 3% of the calculated/expected genotype frequency. Compare heterozygotes to see where the most change is.

Define species

A species is an evolutionarily independent population. If gene flow ends, then populations will evolve independently (so, allele frequencies will diverge).

Evaluate the pros and cons of asexual and sexual reproduction and why a species might switch between the two

A species might switch between sexual and asexual reproduction in order to adjust to environmental cues and variability in their population. For example, in Daphnia, in warmer weather the females use parthenogenesis while in colder weather they use sexual reproduction. Daphnia will only switch to sexual reproduction when the days are shorter, water quality is crowded, and food concentration is low. The reason for this was hypothesized to be because sexually produced offspring have increased genetic variability which means they have greater chance of survival (fitness) in the wild when there's deteriorating environmental conditions.

Define synapomorphy and relate it to the determination of phylogenetic relationships

A synapomorphy is a trait that becomes unique in a monophyletic group, this new lineage makes the organism dissimilar enough to become a new species. This can relate to the whale evolution case study because in that it was assumed that, by morphology, whales aren't closely related to artiodactyls like hippos because whales lack an astragalus bone. However, based on phylogeny and DNA evidence, it was concluded that whales are actually more similar to that group of organisms - more so than the camel (which was more closely related in the group, but now acts as an outgroup). So, it turns out that the whale developed a different synapomorphy than it's sister taxon hippos; this resulted in the lack of the astragalus bone - thus making it a different species.

Compare & contrast the following: promoters, enhancers, promoter-proximal elements, silencers. What constitutes basal transcription factors vs. regulatory transcription factors - this is important, be sure you understand the difference.

A. Promoter - short nucleotide sequence in DNA that binds RNA polymerase, enabling transcription to begin. In prok. DNA, a single promoter often is associated w/several contiguous genes. In euk. DNA, each gene generally has its own promoter. Promoter-proximal elements - in euks., are regulatory sequences in DNA that are close to a promoter and that can bind regulatory transcription factors. Enhancers - regulatory sequence in euk. DNA that may be located far from the gene it controls or within introns of the gene. Binding of specific proteins to an enhancer enhances the transcription of certain genes. Silencers - a regulatory sequence in euk. DNA to which repressor proteins can bind, inhibiting transcription of certain genes. B. Basal transcription factors - are proteins present in all cell types that bind to eukyotic promoters to help initiate transcription = RNA Polymerase and the promoter. Regulatory transcription factors - proteins that bind to DNA regulatory sequences (enhancers, silencers, promoter-proximal elements), but not to the promoter itself, leading to an increase or decrease in the transcription of certain genes.

Evaluate whether a trait is an adaptation

Adaptations are genetic modifications passed down throughout generations (via change in alleles). To be acclimated to something is to get a temporary adjustment to that change in environment

Describe the difference between adaptation and acclimation

Adaptations are genetic modifications passed down throughout generations (via change in alleles). To be acclimated to something is to get a temporary adjustment to that change in environment.

Explain how age structure can affect population growth

Age pyramids are used to find the number of males and females of each age. Age pyramids are uniformed in developed countries so there's relatively a similar amount of older people to younger people. The age pyramidis bottom-heavy (favoring younger people) in developing countries. In addition to being the primary cause of habitat loss and species extinction, overpopulation is linked to declines in living standards, political instability, and acute shortages of basic resources. Projections: (a) modest changes in 2050 due to increased survivorship, but fecundity stays the same. - concern = how will be care for our older population (b) dramatic improvements in healthcare, Hondurans are surviving longer. Fecundity will decrease slightly with education advances, but the problem is going to be jobs etc. for this larger adult population.

Describe allopatric and sympatric speciation

Allopatric speciation is the creation of a species as a result of organisms moving to a different homeland and/or being genetically isolated. Sympatric speciation is the creation of a species when a population is isolated in the same habitat.

Describe why altruism does not contradict the statement "organisms do not do something for the good of the species"

Altruism doesn't contradict the statement that "organisms don't do something for the good of the species" because there is a fitness advantage to doing it. For example: in prairie dogs, the prairie dog with the most kin in the coterie is most likely to give an alarming signal to the rest of the population because, even if they die, if they have a strong chance of their genes being passed on. So, the prairie dogs aren't doing it for the good of their species, but rather so that there's still kin prairie dogs that can pass its genes.

Describe reciprocal altruism

An exchange that takes place over time. This isn't true altruism; they appear to be selfless, but it's because the favor is being returned (actually increases the fitness of the altruist (or actor)). For example: Vervet monkey grooming, and vampire bats sharing food

Analyze the derivatives of the apical and basal cell during embryogenesis

Apical becomes embryo, and basal becomes suspensor.

Define artificial selection and how it differs from natural selection

Artificial selection, or selective breeding, is the process by which humans breed animals and plants in order for each to display phenotypic traits that were especially picked out. Humans breed organisms together with desirable traits in order to have the most wanted traits in the next generation. This is different from natural selection because the environment doesn't choose who gets the chance to reproduce, it's humans that choose which traits are best fit for their needs (the human's needs).

Explain arms race in relation to avoiding consumption

As consumers and prey interact, a coevolutionary arms race begins: Consumer traits increase in efficiency Prey evolves traits to be unpalatable and elusive Selection on consumers for traits that can counter prey's adaption Predators will evolve for increased predation, and the prey will evolve for increased fitness. But then the predator overcomes prey's tactics and evolves (this whole cycle is a back and forth). *It's the dynamic selection for either predator or prey to help with their fitness. Only the prey that escapes predators will spread their genes. It's a selection of traits that help outwit each other.

Describe the average temperatures, temperature variation, average precipitation, and precipitation differs among the 6 primary biomes

Average Temperature Temperature Variation Average Precipitation Precipitation Variation Arctic Tundra VERY LOW HIGH VERY LOW LOW Boreal Forest LOW VERY HIGH LOW LOW Temperate Forest MODERATE MODERATE MODERATE LOW Temperate Grassland MODERATE MODERATE LOW MODERATE Subtropical Desert HIGH MODERATE VERY LOW LOW Tropical Wet Forest HIGH VERY LOW VERY HIGH HIGH

Explain Hamilton's Rule (Br>C)

B = fitness benefit (# of offspring) to recipient C = fitness cost (# of offspring) to altruist r = coefficient of relatedness (varies between 0.0-1.0) - Strangers = 0.0 - Identical Twins = 1.0 - Parent-to-Offspring = 0.5 In this rule, if the benefit to the recipient(s) and the more related the recipients are to the altruist, then the altruist is more likely to do the self-sacrificing behavior. For example, in prairie dogs, if the altruist has more relatives in the population (and there's more benefit than cost), then the altruist will make the call.

Why are Hox genes often called "tool box genes"?

Because the expression of different combinations of Hox genes creates different structures.

Describe the link between bilateral symmetry and triploblasty

Bilateral symmetry is a part of the triploblasty monophyletic group, but arrived as a biologically fit synapomorphy is a part of that. ///Triploblasts have 3 primary germ layers, and the mesoderm. A true advanced mesoderm gives rise to motility and muscularity. Since there's more movement, the animals are interacting with their environment at one end - a central nervous system. This is the link between bilateral symmetry and triploblasty

Evaluate the positives and negatives of each major species concept (when would you use which one)

Biological Species Concept: (+) No DNA, easy, theoretically can see if they mate / (-) fossils; asexual reproduction Morphospecies Concept: (+) easy, no material, by sight / (-) cannot ID cryptic species, subjective, up for debate Phylogenetic Concept: (+) applies to any population, synamorphs differ only if no gene flow / (-) it's difficult because there's a limited amount of DNA for species and their ancestors

Describe biomagnification and why a chemical used in one ecosystem could affect consumers in another.

Biomagnification is chemicals (particularly lipid solubles) that increase in concentrations at higher trophic levels. For example: toxaphene (insecticide) and mercury don't break down, so they're called "POP" (Persistent Organic Pollutant). POP is stored in lipids, so it doesn't get metabolized. So, after each consumer consumes another organism the concentration of that toxin increases. The Arctic Inuit people depend on fish/mammals with high levels of toxaphene - the toxaphene got to the organisms via the wind.

Evaluate what organisms might be found in each of the 3 types of wetlands and in the different zones of oceans and lakes

Bogs: stagnant and acidic, so insect-eating organisms would be found because soil is nutrient-poor Marshes: nonwoody plants Swamps: trees and shrubs Photic Zone: plankton Benthic Zone: detritus eaters Aphotic Zone: ocean animals and ocean feeders

Predict the effect of changing the rate of cellular proliferation.

By increasing the rate of proliferation, it can leave the cells susceptible to the development of tumors (unregulated cell growth)

Describe how anthropogenic effects (human impact) could affect both terrestrial and aquatic biomes

CO2 pollution results in climate change Decreased species diversity Increased global temperature Arctic Tundras gradually become Boreal Forests Decreased biodiversity (environment types)

Evaluate whether a behavior is benefiting close relatives

Calculate the relative closeness using hamilton's rule, to see how probable an individual is going to be selfless depending on the number of kin in the population. In regard to the experimental setup, scientists found the relation between the prairie dogs and then dragged a fake badger near their coterie 700 times over the course of 3 years. They determined that Alarm calling usually benefits relatives because the prairie dog that made the alarms tended to have relatives and/or offspring in the population as well.

Explain the carrying capacity (K) of a population and how population size affects the growth rate

Carrying capacity of a population is the maximum amount of individuals that a habitat can sustain. So, what this means is that at a certain population of individuals, the area cannot sustain more organisms. So this is when carrying capacity is reached; once this is reached, then population growth plateaus and the population size will tend to hover around a specific amount - so, carrying capacity limits the exponential growth of a new population.

Why are cell-suicide genes important during development?

Cell-suicide genes trigger a cell to undergo apoptosis, programmed cell death. During development, removal of tissue via this mechanism is necessary to create certain body structures - ie: webbing between toes or fingers.

Calculate r for close relatives (parent, grandparent, children, aunt/uncle, cousin, full sibling, half sibling)

Child-to-parent: 0.5 Child-to-grandparent: 0.25 Child-to-sibling(full): 0.5 Child-to-uncle/aunt: 0.25 Child-to-sibling(half): 0.25 Child-to-cousin: 0.125

Describe why choanoflagellates are not animals

Choanoflagellates aren't animals because they're not multicellular - they're sessile protists

Explain niche differentiation and character displacement

Competition is a (-/-) interaction, so strong natural selection on both to avoid it. Natural selection favors individuals that don't compete. Niche Differentiation is the equal partitioning of resources when competitors have equal fitness (symmetric competition with no niche overlap). Character displacement is the change in a species' traits that allows for the exploitation of different resources (no competitors).

Evaluate species interactions and determine whether it is competition, consumption, mutualism, or commensalism

Competition: use the same resources (-/-) } lose-lose situation. Examples of these resources include shelter, environment, etc. Both species have a negative impact on fitness. Even if one is better than the other, the better competitor still isn't gaining as much as it could because of the existence of the opposing competitor. So, being better doesn't make a difference. Consumption: one organism eats/absorbs nutrients from other (+/-) (predator & prey) Mutualism: fitness benefits to both (+/+) Commensalism: one species benefits, other species unaffected (+/0). For example, a big population of ants scurry along the floor, and the sounds of a bunch of stampeding ants can be intimidating to insects. The ants don't prey on the insects, but the insects still jump out of the way because they think that the sound of the ants is a large predator. But, the antbird follows populations of ants because they can eat the insects that are jumping. The antbird tagged along and benefitted, but the ants are unaffected.

Describe constitutive defenses and the 2 types of mimicry

Constitutive Defenses are defense systems that are always present and available to prey at all times. Avoidance: examples - camouflage, blending into the background, running away ( a leaf insect disappears among the leaves) Flocking/Schooling: schooling allows for safety in numbers; these large amount of creatures confuse predators into thinking this is a much larger organism Fighting Back: examples - weaponry: fighting back (toxins, poisons on plants), porcupines use their spines to fight back Mimicry: a way for prey to appear differently than what they are in order to offer a fitness advantage. Müllerian mimics look dangerous and are actually dangerous; for example, paper wasps, bumblebees, honey bees. The resemblance of two or more harmful prey species and increased likelihood that predators will avoid them = co-mimicry. Batesian mimics look dangerous, but aren't dangerous; for example, hornet moths, wasp beetles, hoverflies. Predators avoid the harmless mimics because they look dangerous. It takes biological energy to keep up defense mechanisms (constitutive) → make spikes, pigmentation, weapons. PRO: ready at all times. CON: takes biological energy to maintain.

Define convergent evolution

Convergent evolution is when natural selection favors traits for a similar way of life of two different organisms, and this results in homoplasy.

Describe the role of DNA, RNA, and proteins within the Central Dogma

DNA (genotype) → mRNA → amino acids (proteins) → phenotype

Why does DNA form loops near the core promoter in order for transcription to start?

DNA bends in order to bring enhancers and promoter-proximal elements w/their regulatory transcription factors into contact with the basal transcriptional machinery

Someone says "Geneticists spend all their time talking about DNA, but that's silly because DNA isn't that important in the functioning of a cell". In what ways is this statement correct & in what ways is it incorrect?

DNA stores all of the information for all of the proteins your body needs, but it does not actually perform the functions. It is the proteins that give a cells it's phenotype. However, maintaining these proteins or adjusting their levels in response to changing conditions would be impossible if DNA didn't "hold" all the info. at all times.

Describe the role that Charles Darwin and Alfred Russel Wallace played in the development of modern evolutionary thought

Darwin and Wallace established the theory that organisms change over time and descend from a common ancestor. In addition, they developed the idea that evolution occurs by natural selection; this means that, as a result of genetic variation, there are members of the same species who are better fit for their environment, so those members will be the ones to produce more viable offspring in that environment. Darwin's evidence for this came from his observation of the Galapagos finches, and he recognized that members of the same species adapted to different environments over time. /// POPULATION THINKING - changes within populations of species over time

Describe how devegetation affects nutrient export/loss from a system

De-vegetation affects nutrient export/loss from a system because there's nothing left to keep the nutrients and the substances in that area from going down the stream. So, having vegetation prevents these nutrients from running off. 10x more nutrients runoff in the devegetated area than vegetated area. With all this run off, land mass tends to settle and form a 'water table'(the upper limit of saturated soil). So, in devegetated areas the water sinks; the problem with this is that runoff and water from melting glaciers results in a rise in sea levels (our water table is going down); this puts any low-lying areas at sea level at risk for flooding. With our water reserves (glaciers) melting. Examples of this include Bangkok and Miami.

Describe why deceitful communication only works when it is rare

Deceitful communication only works when it is rare because if everyone did it, then it would be more expected. As a result, that method would no longer be effective.

Contrast deuterostomes and protostomes

Deuterostomes: anus develops before mouth during gastrulation in blastula Protostomes: mouth develops before anus during gastrulation in blastula

Describe the role of dormancy

Development can stop and lay dormant by drying out. The embryo gets relatively preserved and stored. Once put in appropriate conditions are surrounding the embryo, then it can start development again.

Specifically, explain what it means to say differentiation is "progressive"?

Differentiation is triggered by the presence or absence of regulatory transcription factors produced in response to external signals (or from cytoplasmic determinant partitioning). These signals trigger the production of transcription factors, which induce other transcription factors and so on - a sequence that constitutes a regulatory cascade - as development progresses. At each step in the cascade, a new subset of genes is activated, resulting in a step-by-step progression from undifferentiated to fully differentiated cells.

Describe two methods of allopatric speciation

Dispersal Allopatry is similar to the founder's effect in that a group of organisms moves to a different location - dispersal, colonization, and genetic drift + selection occurs, two populations are reproductively isolated. Vicariance Allopatry is a chance for physical separation, genetic drift, selection, and population isolation - there has to be a natural physical barrier.

Describe how drug resistance has increased in recent decades

Drug resistance has increased in recent days due to the repeated use of antibiotics. After a round of antibiotics kills off bacteria, there's a chance that one strand of bacteria had a mutation that happened to be resistant to the antibiotics. With the competition wiped out, this mutant bacteria is allowed to reproduce, so the next generation of bacteria will all have the mutation that resists the antibiotic.

Describe vegetative and reproductive development

During vegetative development the SAM (shoot apical meristem) and RAM (root apical meristem) are active and they produce the stem with leaves and roots, respectively. When environmental cues indicate it (shorter nights and warmer temperature), plants will start to modify their SAM in order to become floral meristems and produce reproductive parts (flowers). Suspensor anchors the embryo to the endosperm - the entire basal area will be the suspensor, while the apical side continually grows to become the embryo. The roots grow from the RAM, so the roots develop from the bottom of the apical part. Upon vegetative group, there's no more basal part and the RAM establishes roots.

Describe the role of ecological restoration & some examples

Ecological restoration aims to recreate and accelerate growth in conservation. Some examples of this include establishing wildlife corridors to join metapopulation, sustainability (managing resources and replenishing what was lost), stabilize human pollution, reforestation programs.

Describe how energy flows through an ecosystem including where energy is lost.

Energy from the sun gets converted to glucose via photosynthesis in autotrophs (like plants), then primary consumers eat plants and secondary consumers eat other living things. Then, once those consumers die, decomposers feed off the dead organisms and excretion.

Evaluate why estuaries are so productive

Estuaries are so productive because the river meets the ocean, so there's a mix of freshwater and saltwater. The salinity varies with proximity to the ocean; this then affects osmosis, so the species in estuaries have all adapted to account for this change in salt levels. The young fish feed on plankton & vegetation, while hiding from predators. And the rivers are shallow which allow for a lot of light for photosynthesis; this makes estuaries-nutrient rich. /// slow moving water, so nutrients don't get washed away. Don't have to rely on turnover bc nutrients are constantly being mixed to the top. It's shallow, so photosynthesis occurs since sunlight can penetrate it.

Describe how adaptation is not perfect

Evolution favors groups of species who are better adapted to the environment at the time, so no one can pick traits to better their chances of survival. Adaptations don't occur because organisms need them or want them; it's completely random. Pleiotropy - suboptimal change in a structure that goes along with a good change. Fitness-trade off - one trait proves to be beneficial in one situation but detrimental in another.

Describe why individuals do not do things for the "good of the species"

Evolution isn't goal-directed, so no changes are made in a population for the sole purpose of being good for the whole species. Any mutations or genetic variation isn't planned - everything is random. It's just a matter of which traits are biologically better fit for the environment at the time. /// It isn't to make a species better, it just happens.

Describe why evolution is not goal-directed or progressive

Evolution isn't goal-oriented or progressive because the changes in a species' traits don't happen on command. Additionally, organisms don't get progressively "better", they just become more fit for the current state of their environment.

Explain optimal foraging

Example of "what should I eat & where should I live?" organisms make decisions that maximize food found given cost/risk of finding it. For example: white-fronted bee-eaters make homes where food will be most prevalent → assess the cost and risk of foraging food far from home. (flexible & condition-dependent)

Evaluate the ultimate and proximate causation for different behaviors discussed

Example: Spring Lobsters their find way back to coral reef dens after night of hunting → on an ULTIMATE level, they search for food in the night to avoid predators → on a PROXIMATE level, they use their receptors in the brain that detects Earth's magnetic field

Describe the 3 parts of the logistic growth curve

Exponential - early rapid growth Growth rate begins to slow as competition begins Growth falls to zero when hitting carrying capacity

Explain why exponential population growth is density independent

Exponential population growth is density independent because by not accounting density there's no plateau in the population as a result of increased competition and decreased resources (carrying capacity). In addition, it's unrealistic to not include density because populations don't always grow exponentially, indefinitely. In nature, there are 2 instances where this exponential growth will occur: 1. There's a new population in a habitat, and 2. Population is devastated by catastrophe and recovery starts with a few surviving individuals.

Describe life history trade-offs and the impact of population growth

Fitness Trade-Offs are due to restricted time/energy - females can maximize either fecundity, survival, or a balance of both. For example, birds with low numbers of offspring have more resources to maintain a high level of survival. Birds with high numbers of offspring have less resources, so they have a lower level of survivorship.

Evaluate whether there is a fitness trade-off

Fitness trade-offs are a compromise between traits. While a trait proves beneficial in one way, it can be disadvantageous in another. For example: large eggs could limit the number of offspring and having bright colors could attract mates (but also predators!).

Describe how behaviors fit on the continuum of learning and flexibility

Flexible, learned, correlates with the environment. Animals weigh the risks of certain behavior and know how to correlate it with certain environments over the course of their lifetime & learn what's the best behavior. (Example: animals know to travel out of the nest when there's no predators). There's a Cost-Benefit Analysis which means that animals appear to weigh costs and benefits of responses → measured by impact on fitness.

Describe fossils: where are they found and what information do they provide

Fossils are found in sedimentary rocks, and they provide information about organisms that lived in the past, how old these organisms existed, and how species have changed diachronically. Darwin primarily used fossils as evidence for his theories.

Analyze gene function based on a mutants in regards to anterior - posterior axis formation of a fruit fly

Fruit flies that have a mutation in the formation of the anterior - posterior axis, have a problem with the distribution of the master regulator because this is what forms the axis.

Describe the role of fruits in plant development

Fruits act as a physical barrier between seeds and the external environment for protection and in some cases to prevent premature germination. In addition, fruit acts as a method for seed dispersion when animals take the fruit to different locations in order to consume it then the seeds get plants somewhere else. Fruits just carry the seeds.

Describe the germ layers formed as a result of gastrulation.

Gastrulation is when cells in the early embryo mass rearrange into three embryonic tissues (germ layers) in order to later become specific organs later on (blastula → gastrula). The blastopore at the bottom of the gastrula gets pushed inwards to eventually become the mouth-to-anus track (digestive track). The cells around the digestive track will become the endoderm.

Which event in animal embryogenesis involves coordinated cell movement? What is the result?

Gastrulation. Results in establishment of the primary body axes and organization of the 3 embryonic tissue layers - endoderm, mesoderm & ectoderm.

Evaluate evidence that species are related by common ancestry

Genetic evidence can be very detailed and can pinpoint exactly where organisms are similar; however, this technology isn't accessible to everyone. Looking at the similarities in adult morphology you could evaluate the placements of similar bones amongst different animals; however, organisms with similar structure aren't always closely related, but sometimes develop similar features as a result of selective pressure. Another form of evidence would be looking at animal embryos (particularly humans, cats, and chickens) and finding similar organs like tails found.

Evaluate the effects of habitat destruction

Habitat destruction in an area that's a hotspot like the Brazilian Tropical Wet Forest has decreased precipitation which leads to soil erosion and desert-like conditions.

Evaluate the benefits from healthy ecosystems

Healthy ecosystems have increased biodiversity and help to sustain food chains by providing NPP to higher trophic levels (including humans)

Describe the three types of consumption

Herbivory: organism that feeds on plants Parasitism: An organism that feeds off something (usually a different organism) at the other organism's expense Predation: the preying of one animal on others

Evaluate what type of homology a trait could be

Homology is the study of likeness between organisms due to common ancestry. Morphological, Developmental, and Structural.

Evaluate whether a trait is a homology or homoplasy using a phylogeny

Homology: traits similar due to shared ancestry Homoplasy: traits similar for reasons other than ancestry

Describe hotspots and why they are good targets of conservation efforts

Hotspots are areas with high amounts of native species (1500+) that are experiencing large amounts of loss (>70%). They are good targets because they make up a small part of the Earth's surface, but >50% plant/ 42% animal species.

Evaluate methods that plants have evolved to promote dispersal

How do plants achieve dispersal of genetic material? Wind, Water, Pollinators.

Explain how humans impact other populations

Humans are growing larger and larger as a total population, and in order to sustain that population humans have to take up more space. By taking up more space, more of other species' habitats are being destroyed. An example of this would be the endangered species of butterfly (Granville fritillaries); they exist naturally as metapopulations and they have to keep moving.

Determine what happens to the body if the bicoid gradient is altered in different ways.

If the bicoid gradient is altered then the types of structures that form on the organism will be altered. For example, if the bicoid gradient was evenly distributed, then the entire organism will have activators for anterior structures - they'll express the same genes.

Explain the logic behind using nuclear transplant experiments to test if animal cells are genetically equivalent. Include what the donated nucleus contributes vs. the egg.

If the transplanted nucleus has undergone some permanent change or loss of genetic information during development, it should not be able to direct the development of a viable adult. But if the transplanted nucleus is genetically equivalent to the nucleus of a fertilized egg, then it should be capable of directing the development of a new individual. The donated nucleus contributes the genetic information & the egg contributes nutrition and cytoplasmic determinants needed to initiate embryogenesis.

Explain immigration, emigration, and demography

Immigration: the process of individuals moving into range from elsewhere Emigration: the process of individuals moving out of the population range Demography: study of factors influencing size/structure of a population over time

Describe the difference between internal and external fertilization

In animals that perform internal fertilization, tend to have sperm and egg directly come in contact with each other directly from the parents reproductive organs. Two forms of internal fertilization include copulation and spermatophore. In copulation, sperm directly deposited into the female reproductive tract. In spermatophore, males package sperm and women pick it up. Externally fertilizing animals have a jelly layer surrounding the egg - in addition to the vitelline envelope - while internally fertilizing animals only have the vitelline envelope. There are certain conditions that must be met for both internal and external fertilization: species-specific recognition of gametes, same place & same time (for external: pheromones, change in time & day, change in climate, mating calls), sperm needs to reach the egg, and fertilization must kick off development.

Describe inclusive fitness

In any act that benefits an individual's fitness, this act also increases the fitness of others as well. For example, the prairie dog that makes the alarm call gets a fitness advantage of protecting the kin who can spread the altruist's genes, but the population hearing the alarm has the advantage of getting protection. /// The addition of one's own fitness plus those around them who they save.

Determine whether sexual selection is acting via female choice or male-male competition

In order to identify sexual selection, see whether or not there's a difference in ability between males and females in their method of attracting mates. If it's a female choice, then the males will display brighter, more flamboyant traits in order to signal to females that they have healthier genes to pass on (sexual dimorphism). When it's male-male competition, the male organisms will fight against each other and winners will be the ones who can reproduce, so many of the males (losers) will not pass on their alleles - it's not a female's choice, but what male organisms get the "right" to reproduce.

Describe why inbreeding does not cause evolution

Inbreeding doesn't cause evolution because it results in the increased frequency of homozygotes in the genotypes. What this means is that there's a heterozygote depression since there's a progressively lower rate of heterozygotes due to inbreeding. There's also a decrease in the heterozygote advantage (having genetic variation) - this violates Darwin's postulate that a population must have genetic variation in order for evolution to take place.

Explain interspecific and intraspecific competition

Intraspecific Competition: competition within the same species (density-dependent). Example: one species is eating seeds of a certain range Interspecific Competition: different species are competing to use the same resources, there's a partial niche overlap for the competition of resources

Explain competitive exclusion principle

It is nearly impossible for species' with the same niche to coexist indefinitely - if one is a better competitor than the other. An example of this is P.aurelia and P.caudatum; when they occupy the same niche, P.aurelia is the stronger competitor, so its population will grow. As a result, P.caudatum will go extinct. This example also displays asymmetric competition.

Describe keystone species and how to know if a species is a keystone

Keystone species are species with a greater impact on others than its abundance would suggest. You can tell if a species is keystone by taking it out of the population, and observing the amount of species present. If there's a sudden drop in biodiversity over time, then the species that was removed was a keystone species.

Describe the role Lamarck played in the development of modern evolutionary thought

Lamark introduced the idea that evolution is a diachronic change and that chains of organisms exist because their acquired traits are heritable. Darwin and Wallace used the idea of diachronic change in their proposal of evolution by natural selection. Instead of building on the idea that acquired traits were heritable, they proposed that genetic diversity was necessary in order to have evolution in the first place. /// Determined that change was important, but still believed in typological thinking. He believed acquired traits are inherited.

Evaluation how leaf shape is linked to the environment is found in

Leaf shape can be altered through phenotypic plasticity depending on the environment it grew in (even if compared to a plant of the same species in a different area). High surface area in leaves maximizes photon absorbency while leaves with smaller surfaces areas decrease water-loss. The leaves will grow differently and change depending on what it needs most (kinda like an eye dilating in the dark and contracting in the light).

Explain the parts of a life table

Life tables summarize the probability of an individual surviving/reproducing over time. Survivorship is the portion of offspring that survive to a particular age. Fecundity is the number of offspring produced by each female in the population. Growth rate tends to depend entirely on females, so in a life table - there's only female data. (Survivorship) * (Fecundity) = Average # of offspring produced per female of age (x). This data can help determine if a population is growing or declining. So, you take the sum of the (survivorship)*(fecundity). If it equals 1 then it's stable, if it's greater than 1 then it's growing, if it's less than 1 then it's declining.

Evaluate data on global climate change

Look at the effect of climate change on different species and in different ecosystems.

List the steps in the regulatory cascade of early development in fruit flies

Master regulators set up the body axes (anterior - posterior / dorsal - ventral / right - left ) in fruit flies. These lead to a series of gene-activating signals (through activators that make activators) which fine tune the control over what a cell becomes - this is known as the cascade. The first step is cleavage in the process of embryogenesis - in which rapid cell division occurs and the uneven distribution of the cytoplasmic determinant. The blastula forms (and the smaller cells within it are called blastomeres). Next is Pattern/Axis Formation: the master regulator, bicoid, is anchored on the anterior side of the organism and the protein diffuse towards the posterior creating a concentration gradient. The absence of bicoid promotes the development of posterior structures. The master regulator establishes the anterior - posterior gradient of embryo. Gap genes are then produced, and they organize cells into groups and segments along anterior - posterior axis. Next, the pair-rule genes organize cells into individual segments. Then, segment polarity genes establish anterior - posterior gradient within each segment. That's the end of the segmentation genes, finally, the homeotic genes trigger the development of structures (limbs). Effector genes change proliferation, death, movement, and differentiation of cells.

Explain why membrane binding proteins are critical for species recognition

Membrane-binding proteins are important for species recognition because they aid the start of fertilization by directing the sperm to the egg, and allowing for the binding to take place. In addition, this contributes to helping the gametes interact at the same time which is a condition that needs to be fulfilled for the start of fertilization.

What are some similarities & differences between the division taking place during cleavage and mitosis?

Mitosis makes daughter cells that are the same as the parent cell. During cleavage, the blastomeres become smaller & smaller with as division continues & cytoplasmic determinants within the fertilized egg becomes partitioned into different blastomeres.

Identify monophyletic group, node, branches, polytomy, sister taxa, and outgroup on a phylogeny

Monophyletic group: (clade) ancestral population & all their descendents Node: where ancestral group splits, the common ancestor of a taxa Branches: population throughout time Polytomy: more than one branch emerging from a node Sister taxa: taxon from the same closest descendent Outgroup: a taxon that has the least similarity to the other groups, and acts as a point of reference.

Describe kin selection

Most behaviors aim to increase individual fitness, even altruism. While altruism may seem to be decreasing an individual's fitness advantage, it's actually not. For example, the prairie dogs do the alarm calling when there's mainly a lot of kin and/or offspring in that population as well. So, there's a fitness advantage in helping a population that has more of your kin.

Evaluate evidence that species change through time

Most of the evidence for this derives from looking at ancestral populations and comparing them to the same organism today. Fossils are traces of past organisms that can be used for modern-day comparisons and radioactively dated in order to determine absolute ages. Darwin also used transitional features in the evolution of tetrapods as an example. Transitional features are mapped out over millions of years through the law of succession (extinct species succeeded by similar species). For example, at some point aquatic animals with fins became terrestrial with limbs as a result of millions of years of natural selection throughout a population.

Describe how NPP and biodiversity differs in the 6 primary biomes

NPP stands for Net Primary Productivity which means that the nature of a biome is governed by average +/- variations in temperature and yearly precipitation. NPP can be calculated by subtracting the amount of fixed oxidized carbon from total yearly fixed carbon - the difference between the two results in organic matter available as food for organisms. /// Assess NPP based on how warm and wet they are. Mostly know about extremes.

Describe water flow, water temperature, oxygen level, and nutrient concentration at different points along a stream

Near the source of a stream: water is fast, cold, nutrient-poor, high in O2, few organisms (mainly animals) Later in the stream: water slows down, warmer, nutrient-rich, low in O2, higher biodiversity (varied organisms - algae, plants, animals)

Describe how changes in homeotic genes have been critical for animal evolution

Nonlethal changes in homeotic genes have been critical for animal evolution because they provide mutations that can adapt and survive in different environments. And when those organisms with the mutation reproduce that mutation could eventually be passed on. If this mutation is beneficial to survival in that environment then it'll help that part of the species outcompete in the wild as a result of their advantage.

Explain why nutrients are so important in aquatic environments

Nutrients are important to feed herbivores and omnivores in aquatic environments. Vegetation is the foundation of the food chain, and without it the chain cannot start.

Explain why one may get mercury poisoning from eating a top predator versus eating the same amount from a primary consumer

One may get mercury poisoning from eating a top predator versus eating the same amount from a primary consumer because lipid soluble tends to stay sequestered in consumer fats & liver cells instead of getting excreted, and top predators have a lot more fat.

Evaluate whether a species is using optimal foraging using data on foraging activity

Optimal foraging is the distance the animal travels from its home and its pay off. Over a period of time measure how far it travels and how much food it gets. If it gets less food even though it travels farther, then that's not optimal forging.

Describe the 4 types/levels of ecology

Organismal Ecology: how do individuals interact with each other and their physical environment? Population Ecology: how and why does population size change over time? Community Ecology: how do species interact, and what're the consequences? Ecosystem Ecology: how do energy and nutrients cycle through the environment?

Explain why photosynthesis and energy transfer between trophic levels is not 100% efficient

Photosynthesis isn't 100% efficient because 45% of incoming sunlight goes into NPP, and the other 55% goes into maintenance or is lost as heat. Energy transfer between trophic levels is not 100% efficient because only 1.6% of energy from plants goes to growth and reproduction

Define phylogeny

Phylogeny is the evolutionary development and diversification of a species or group of organisms - or a particular part of an organism. Map of descent and ancestry, tree of relatedness - particularly prevalent with Darwin's finches. Use genetic, developmental, and structural homology to compare. Those closer on the phylogenetic tree are more closely related, but all organisms on the tree are related to a common ancestor.

Describe how the theories of Plato and Aristotle differ from Darwin

Plato and Aristotle's thinking about evolution focused on individual changes and spontaneous generation. While Darwin (& Wallace) believed in changes in groups as a result of variation in population over time. Unlike Plato, Darwin believed that there needed to be genetic diversity in order for natural selection to take place. /// TYPOLOGICAL THINKING - species are unchanging, and any changes that occur during the lifetime are unimportant, individuals

Analyze the difference(s) in wind and insect pollinated plants

Pollination syndromes: insect - nectar, bright pigments, fragrant. Wind - more random and not completely dependable, so reproductive parts are very out in the open. 1. Wind-Pollinated Plants Anthers are large and hang outwards Small non colorful 2. Insect-Pollinated Plants Sweet smelling Presence of Nectar Brightly colored

Explain why population density might affect r

Population density might affect r because it'll account for resources and competition, so the growth in a population won't be exponential for as long of a period of time. In addition, when population density gets high, the average birth rate decreases and the average death rate increases; therefore, the value of r decreases.

Distinguish Porifera, Cnidaria, and Ctenophores based on key characteristics

Poriferans (sponges), Cnidaria, and Ctenophores are all multicellular, so they qualify as animals. However, what distinguishes them is that Cnidaria and Ctenophores are diploblastic, have radial symmetry, have neurons (nerve net), and have muscle cells.

Predict the effect of modification of each step in 19.1

Predict the effect of modification in differential gene expression (Day 1 slide). You can add an activator to a cell or change it, you'll change the expression pattern.

Describe energy flow through a food web using a referenced figure.

Producer → Primary Consumer (20% of producer energy) → Secondary Consumer (15% of producer energy) → Top Predator or Tertiary Consumer (10% of producer energy)

Explain growth rate = N*r and r=b-d

Rate = N*r is density-independent growth rate, so it's the change in the number of individuals per unit time. N represents the number of individuals, and r is the per-capita rate of increase; this value can be derived from r = births - deaths. The definition of 'r' in this case is the difference between the amount of births and the amount of deaths.

Describe the two different types of dances that honeybees use to communicate

Round Dance: is done when food is with 80-100 meters of the hive Waggle Dance: food is farther than 100 meters, waggle dance DOWNWARDS means food is opposite direction of sun, waggle dance SIDEWAYS means food is 90° to the right of the sun

Define sexual dimorphic traits

Sexual Dimorphic traits are traits that are significantly different between females and males of a species. Sexual Selection is responsible for very exaggerated phenotypes being found in males in order to attract a female mate, and the female can see these traits and preferentially pick the most exaggerated phenotype because it means that male has good genes. Example, females pick barn swallows with longer tails because they can fly better, so they'll be a better provider.

Describe the difference between sexual and asexual reproduction

Sexual Reproduction: Requires a partner Genetic diversity Offspring similar to parents Based on gamete formation from meiosis (and for plants mitosis too) Asexual Reproduction: No partner required Faster Offspring identical to parent Based on mitosis Population susceptible to disease

Describe sexual selection

Sexual Selection is the difference in ability to attract mates - female choice versus male-male competition. For example: Male zebra finches with more orange in their beaks are seen as healthier because of the increased carotenoids; this is indicative of good genes to females (female choice).

Describe the parts of a plant and what each part is responsible for

Shoot system: harvests light and CO2. Nodes - where leaves attach, internodes - between nodes, leaf - photosynthetic organs that can alter morphology for absorbance versus transpiration, axillary buds - nodes where leaves attach that may turn into a branch, apical bud - at tip of stem/branch growth here extends the length Root system: anchors, absorbs H2O/nutrients from the soil Vascular tissue: responsible transport of H2O/nutrients

Describe how the amount of solar radiation is affected by both the shape and tilt of Earth

Since the Earth is a sphere, there's varying levels of solar radiation that impacts the Earth (why the tropics are warm and the poles are cold). The equator receives solar radiation at a 90 degree angle, so there's always sunlight directly overhead (larger amounts of sunlight per unit area). At 30N, a moderate amount of solar radiation is received because there's a slightly more acute angle of exposure. At 60N, a low angle of solar radiation is received, so there's less incoming sunlight. The 23.5 degree tilt of the Earth is the reason why seasons exist. As a result of the Earth's orbit around the sun in a counter-clockwise direction, the sun rises in the east and sets in the west. There are diminished seasonal changes as the Earth moves during spring and fall.

Differentiate sensory systems, feeding strategies, and limb types among animals

Specialized Sensory Abilities: 1. Magnetism: detects magnetic fields to aid in navigation, 2. Electric Fields: aquatic predators detect electrical action in prey, 3. Barometric Pressure: some birds sense air pressure - storms. /// The nerve net: there's an equal distribution of neurons around the body. The bilateral symmetry and cephalization: nerves cluster together as a ganglia in one part of the body. Feeding Strategies: 1. Suspension/Filter Feeders: filter-out practices suspended in H2O (water moves food to them, so usually sessile), 2. Deposit Feeders: eats via substrates and have simple mouthparts so they eat organic matter through the floor and burrow on the floor, 3. Fluid Feeders: suck up liquid and have mouth parts that can piece and draw fluids like nectar or blood, 4. Mass Feeders: eats food in large chunks with radula like snails and teeth like horses. Limb functions in Animals: 1. Find food, 2. Find mates, 3. Escaping predators. Limbs were a major innovation that helped establish controlled and rapid movements. Jointed limbs are fast like crabs while unjointed limbs are more ancestral and slower.

Evaluate whether a species shows a transitional trait

Species that show transitional traits will show a combination of traits from preceding species and the species that followed it. Need to look at the ancestors and the next generations and see whether it's in the midst of transitioning.

Analyze how the surface area to volume ratio differs between structure adapted for absorption versus storage

Structures that favor absorbency will have a greater surface area (flatter and thinner) than those that favor decreased transpiration more. The volume of both types of leaves would remain the same, but the way the leaves are shaped indicates that specialized development that that plant has made based on its environment.

Describe how sympatric speciation can occur

Sympatric speciation can occur if a group of organisms prefer a specific environment that results in nonrandom mating, and eventually the populations become reproductively isolated. This is happening with the apple maggot flies and the hawthorn maggot flies, and they are close to becoming two distinct species as a result of their preferences for the habitat. One subset of the population has to prefer a niche in the environment, and those organisms mate with each other. Structurally, they could reproduce, but they aren't.

Calculate whether a population will increase based on a life table

Take the sum of (survivorship)*(fecundity) and if it's greater than 1 it's increasing. If it's less than 1 it's decreasing. And, if it's equal to 1, then it's stable.

Describe the effects of climate change on temperature, water/carbon cycles, organisms, and NPP

Temperature: by 2100 the global temp will rise 6.1C Water/carbon Cycles: temperature of surface water is increasing, making it less dense and making the steeper gradient. Deforestation and fossil fuels burning increase [CO2] in the atmosphere and raises global temperature (greenhouse effect). Organisms: geographic ranges for organisms are changing, timing for seasonal events are changing, coral bleaching NPP: declining in aquatic environments due to decrease in nutrients brought to the surface, NPP decreases with the decrease of the fishes from the fishing industry

Describe how Hadley cells control where rainforests are and where deserts are

The Hadley cell is a major cycle in global air circulation responsible for wet tropics. First, the air is heated by the direct sunlight from the equator, then, as a result, the warm moisture-holding air rises. As the warm air rises it is cooling gradually by radiating its heat. In addition, the warm air cooling makes the moisture condense into precipitation along the equator - creating rainforests. The cooler "older" air is pushed towards the poles as more air travels up the cell. Since that air mass is continually cooling, it's density is increasing as well - so this colder air sinks back down. As it sinks, it warms and gains more moisture again - resulting in 30N and 30S being dry deserts.

Describe how speciation is used in practice

The Nigrescens were becoming extinct, and scientists used biological species and morphospecies concepts to determine which species of birds that the Nigrescens mate with to increase the population size. But through the phylogenetic concept, other scientists determined that the two species of birds being bred are actually different species. So, instead of increasing the total genetic pool of that type of bird, they made the new Nigrescens different from the original population. // Describe how speciation is used in practice - biological species concept, morphology, phylogenetic.

Describe how light is affected by water depth and the implications of where light is found in aquatic habitats

The deeper the water, the less light than can penetrate deeper. So, there's higher productivity in shallow water because more light can penetrate through resulting in greater photosynthesis. Where light is found in aquatic habitats results in increased photosynthetic growth and greater vegetation. wavelength = 425 & 680

Describe the major causes of species decline

The major causes of species decline include habitat loss (#1 cause for >90% of species), overexploitation in marine environments, and pollution in freshwater ecosystems.

Describe the role of gap genes, pair-rule genes, segmentation genes, and homeotic genes in development of the fruit fly

The master regulator establishes the anterior - posterior gradient of embryo. Gap genes are then produced, and they organize cells into groups and segments along anterior - posterior axis. Next, the pair-rule genes organize cells into individual segments. Then, segment polarity genes establish anterior - posterior gradient within each segment. That's the end of the segmentation genes, finally, the homeotic genes trigger the development of structures (limbs). Effector genes change proliferation, death, movement, and differentiation of cells

Describe how cytoplasmic determinants affect cellular differentiation

The maternal egg has a certain amount of the master regulator, cytoplasmic determinant (bicoid), so when the zygote divides during cleavage that certain amount of determinant (that's shifted to one side) is unevenly distributed. So only certain cells get the instruction to create activators for different parts of the organism. This contributes to a cascade of activators activating other activators that turn on regulatory transcription factors for some things in certain places and not others. The location where most of the bicoid is in the blastula will become the anterior part of the body and the rest will be posterior.

Evaluate how the amount of solar radiation impacts the organisms found in a locale

The more solar radiation there is, the greater photosynthetic development; this particularly applies to aquatic biomes. Light impacts the amount of productivity. The angle at which the sun hits different areas of the globe is a result of the spherical nature of the planet. So there'll be more biodiversity because of the increased solar radiation per unit area of that area.

You are studying a "loss of function mutation" in a eukaryotic gene. In analyzing the gene sequence, it is surprisingly exactly the same as the wild-type gene within the coding region (between the transcriptional start site and termination site). Explain where the mutation might be & what it is causing.

The mutation is likely in a regulatory sequence, either in the promoter, a proximal control element, or enhancer. Since this is a loss-of-function mutation, the mutation is probably acting to reduce or prevent transcription initiation. The mutation shows the importance of alterations of regulatory sequences outside of coding regions - they can have a major affect on gene function.

Design an experiment that tests the hypothesis that the notochord is needed for neural tube formation

The neural tube develops in the mesoderm. The notochord is a temporary structure that signals for the development of the central nervous system (ectoderm). The notochord puckers up and initiates its start, but the notochord itself is not the spinal column. To make an experiment, just take out the notochord and see whether or not a neural tube/spinal column is formed.

Describe maternal inheritance and its role in animal development

The one thing maternally inherited is cytoplasmic determinant (master regulator); these are maternally inherited. The form of the master regulator in the egg (in flies it's bicoid) is the short mRNA for it is anchored to one side of the egg. Different species have different master regulators with different names. This mRNA is translated to a protein that creates a concentration gradient when going through development. The master regulator (where it's primarily concentrated) creates anterior (head) structures. If this concentration gradient didn't occur, then you have to consider what would be there in place of anterior and posterior.

Describe types of modified roots and their functions

The primary purpose of the roots are the anchor the plant to the ground and to absorb nutrients from the ground. Different environments call for different needs for roots other than its primary purposes. Adventitious roots develop from the shoot (brace in the wind; clings to ivy). Pneumatophores (lateral roots) promote gaseous exchange in a watery environment where it's more essential to get gas, so the roots grow upwards. Contractile roots (bulbs) are shortened and pull plants deeper.

Describe the role of roots and diversity of different root systems

The primary purpose of the roots are the anchor the plant to the ground and to absorb nutrients from the ground. Root systems can be diverse morphologically, phenotypically, and with modified roots. Morphological: differences in appearance between roots for different purposes. Phenotypic plasticity: the ability to change appearance in order to optimize use & adapt because plants are immobile. Modified roots: changed for a purpose other than collecting water.

Describe the embryonic tissue layers in plants

The radial axis layers are the epidermis (protection), ground tissue (middle - stores nutrients), vascular tissue (food & H2O transport). Radial axis layers analogous in plants: endoderm (water & nutrients up in down), mesoderm (middle - store nutrients, structure, xylem and phloem), ectoderm (protection "epidermal" layer).

Describe the role of leaves and diversity of different leaf systems

The role of leaves are to act as organs to conduct photosynthesis - primarily their main goals are to increase absorbency and decrease transpiration. Leaves generally consist of a blade (the leaf part) and a petiole (stalk). Species of plants can have leaves with varying characteristics in order to optimize photosynthesis for that environment. Compound leaves have blades diverged into leaflets. Doubly compound leaves are large but rarely damaged by rain or wind. Also, species from very hot or very cold climates have needle-like leaves.

Describe the role of stems and diversity of different stem systems

The role of stems is to transport materials upwards from the roots into the plant and the role of shoots, in general, to grow vertically to collect CO2 and photons. The diversity of different stem systems allow for plants of different species to harvest light at different locations, minimizing competition. It also allows them to thrive in a wide array of habitats.

Determine characteristics present in an animal group by reading a phylogeny

The synapomorphies at the nodes will indicate what each monophyletic group has.

Describe differential gene expression & how one cell/tissue type becomes different than another

There are certain regulatory transcription factors within cells during transcription that activate only certain genes to be transcribed and expressed at certain times despite each cell having the same amount and type of DNA.

Describe what a rain shadow is

There are regional effects on climate; for example, mountain ranges produce extremes in precipitation. The rain shadow effect is that winds from ocean cool air and drop precipitation on one side of the mountain range, creating high deserts on the other side. The warm moisture-holding air from the ocean. Then, as the air rises towards the peak of the mountain, the air cools and the moisture condenses to precipitation. The remaining dry air passes the crest, and creates desert conditions on the other side of the mountain (rain shadow area).

Describe how biotic and abiotic factors can interact including how we could test for these interactions

There are three abiotic factors that affect organisms: nutrient availability, H2O depth, & H2O movement. Nutrient availability can be tested through observation of ocean upwelling and lake turnover which is how water flows. Water depth dictates how much water reaches organisms (for photosynthesis); light influences that amount of carbon fixed yearly. /// Annual rainfall and plotting a graph, average annual temperatures, biotic is more predator versus prey and how each affect biodiversity, if you remove base level organism how does that affect biodiversity

Recent research has shown that the products of 2 different Drosophila genes are required to keep bicoid mRNA concentrated at the anterior end of the egg. In individuals with mutant forms of these proteins, bicoid diffuses farther toward the posterior pole than it normally does. Predict what effect these mutations will have on larva segmentation.

There would be more bicoid protein farther toward the posterior and less in the anterior - meaning that the anterior segments would be "less anterior" in their characteristics and the posterior segments would be "more anterior".

Analyze how auxin is a master regulator

There's a concentration gradient of auxin found in the egg. As a result of this gradient - like bicoid / cytoplasmic determinant - different regulatory transcription factors (activators) are unevenly distributed resulting in a cascade that determines what kinds of activators are produced in what parts of the organism. ****Auxin is maternally inherited, and you end up with it in the fertilized egg. And the first asymmetric division in the cells establishes the apical-basal axis.

Explain inducible defenses and the pros and cons of it vs. constitutive

These kinds of defense are produced in response to predators, so they are energy efficient, but much slower. For example, the blue mussel is a typical prey to the crab. When no predator is present, typically, the mussel (sessile) attaches itself to a rock substrate using s strictly substance - attachment strength is quite weak. But if crab were to come by, and the mussel sensed it beforehand, then the mussels can increase the thickness of their shells and attachment to the rock (by turning on synthesis of sticky substance). PRO: not using bio energy all the time CON: takes a lot of time, could be fatal

What are meristems & stem cells?

They are undifferentiated cells with the potential to divide indefinitely.

Blastomeres look identical. What makes them actually very different?

They contain different types and/or concentrations of cytoplasmic determinants.

Explain rmax

This is the intrinsic rate of increase, so this is the r-value in which there is a maximum amount of birthrates and a minimum amount of death rates. So, change in N / change in t = r-max * N. r-max * N is the maximum population increase.

How might a deletion in the region -30 or -35 nucleotides upstream of a transcriptional start site affect transcription?

This upstream region is located within the promoter region for the gene. If there is a significant mutation within the promoter of a gene, RNA Polymerase most likely cannot bind and transcription of this gene would not occur.

Calculate allele frequencies from genotype frequencies

To calculate allele frequencies from genotype frequencies, take the genotype frequency of pp and multiply it by (pq)/2. Next, take the genotype frequency of qq and multiply it by (pq)/2. The result should be a decimal for P and a decimal for Q, and these should sum up to 1.00.

Calculate expected genotype frequencies from allele frequencies

To calculate expected genotype frequencies from allele frequencies: (P)^2, (Q)^2, 2(P)(Q). To determine if the Hardy Weinberg equilibrium is in balance, see whether these expected genotype frequencies match the observed within 3%.

Calculate observed genotype frequencies

To calculate the observed genotype frequencies, divide the amount of organisms with pp, pq, and qq. You leave the number as a decimal (don't turn it into a percent).

Evaluate if a trait exhibits phenotypic plasticity

To determine whether a trait in a particular species of plant is exhibiting phenotypic plasticity, compare this trait to other plants of the species that are grown in different areas. An experiment was conducted similar to this in which genetic cues and environmental influence were compared. This is because genetically identical plants can have different systems when grown in different environments.

Define transcription and translation

Transcription is the process of using a DNA template to make an RNA molecule using complementary base-pairing. Translation is the process of using the information in mRNA to synthesize proteins, the information stored in mRNA is translated into proteins by ribosomes.

Evaluate the key characteristics for the three types of survivorship curves

Type 1 Survivorship Curve: (high) (humans) young = INCREASED survivorship, old = DECREASED survivorship Type 2 Survivorship Curve: (steady) (songbirds) linear negative line from young to old Type 3 Survivorship Curve: (low) (young- seedlings, old- plants) young = DECREASED survivorship, but if those young survive, then they last long, so old INCREASED.

Explain what each type is most sensitive to

Type 3- come up with a way for more of their young to survive, most sensitive to low survivorship at birth Type 1- don't have a lot of young but have good survivorship for young people, what they would benefit most is having more young per individual or to increase longevity. Type 2- is equally sensitive to both having more young people and old people survive, so they should increase their health over time.

Describe why bicoid is considered to be a master regulator

Typically bicoid is spread from the anterior to the posterior, where bicoid is most concentrated is where anterior limbs would form. Bicoid is an activatory that activates regulatory transcription factors that promote the cascade of increased gene specificity in different parts of the organism. Mutants would have an abnormal distribution of bicoid, resulting in anterior limbs forming in the posterior and vice versa.

Explain ultimate and proximate causation

Ultimate Causation: (evolutionary) causation that explains why actions occur (evolutionary consequences? fitness?) Proximate Causation: (mechanistic) causation explains how actions occur (neurological, hormonal, skeletal-muscular mechanisms)

Describe vestigial trait and give an example

Vestigial traits are structures that are leftover, so due to incomplete development this structure exists with reduced-to-little function. Examples of this would be the human tailbone (human coccyx) and goosebumps (arrector pili muscles). When vestigial traits cause problems for the organism, this is known as vestigial baggage. /// Vestigial traits show we are related to an ancestor, often the trait becomes smaller as use diminishes.

Describe what happens when individuals occupy the same niche (either symmetric or asymmetric)

When individuals occupy the same niche, there can be asymmetric or symmetric competition. Asymmetric competition is when there is a much stronger competitor of the two species occupying the niche, and this will eventually lead the weaker one to extinction. Symmetric competition is when competitors occupy the same niche but their respective fitness drops equally; therefore, they're both at the same fitness.

Explain how ocean upwelling affects location of nutrients

Wind blows thus moving H2O at the surface Surface H2O moves offshore Upwelling occurs as surface H2O leaves, replaced by nutrient-rich H2O from bottom

Explain lake turnover and thermocline on a season by season basis

Winter Stratification: Dense 4C water at the bottom gets nutrient-rich, colder H2O at surface gets O2 rich Spring Turnover: surface H2O warms to 4C and sinks. O2 is sunk downwards, and nutrients are brought up "SPRING BLOOM" Summer Stratification: dense 4C water at bottom gets nutrient-rich, warmer H2O at surface gets O2 Fall Turnover: surface H2O cools to 4C and sinks, taking O2 down and nutrients up.

Within a multicellular organism, why does 1 cell express a certain gene, but another cell does not?

Within a multicellular organism, all of the cells contain the same DNA sequences. However, one cell may express a certain gene at a given time, but others may not express this gene. This is because only certain cells contain the regulatory transcription factors needed to initiate expression. These transcription factors arise only in certain cells in 2 ways: they may be the result of cytoplasmic partitioning during cleavage they may be produced only in certain cells in response to signals that arrive from other cells during embryonic development.

Use a life table to determine the survivorship curve for a population

X-axis: Age over time, Y-axis: Survivorship. Look at next question for key characteristics to determine which kind of curve you make.


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