Biol 355 Final Exam Questions With Verified Solutions Latest Update 2026

BIOL 355 FINAL EXAM QUESTIONS WITH VERIFIED SOLUTIONS LATEST UPDATE 2026 A single mutation is more likely to affect ___________ because __________ - Answers prokaryotes and viruses because a much larger percentage of the genome is coding a species with defenses is imitated by another species lacking defenses. This is known as _______________. Example? - Answers Batesian mimicry. African swallowtail acquisition of new functions in gene variation is known as ____________. Example? - Answers Neofunctionalization. 1. Antifreeze protein in Antarctic eelpout derived from a common vertebrate gene Are all organisms becoming more complex? Example? - Answers Most are, but there are still some that have lost complexity (e.g. some crustacean lineages) Are you more likely to see a high rate of change if you sample a short or long time frame? - Answers A short one, because evolution often comes in burst. So you may choose to sample a time when the burst is occuring Brood parasitism by cuckoos is an example of __________. Explain - Answers Host parasite-coevolution. Cuckoo nestlings hatch first, toss out host's eggs. Cuckoos evolve to make inconspicuous mimics. Host evolve to recognize cuckoo eggs Can changes in gene expression lead to rapid changes in phenotype? Example? - Answers Yes, different gene expressed in mosquitoes for where they are to detect prey with olfactory system Coevolution - Answers Process by which two species evolve in response to changes in each other Consequences of whole genome duplication - Answers provides opportunity for the evolution of novel genes. Evolution able to act quicker. Some organisms can handle it better. Benefits can be countered by gene dosage affects. Differential rates of growth in one dimension (height) relative to another dimension (width) changes shape. This is known as ____________. Example? - Answers Allometric growth. Stag beetles mandibles grew faster then the body. Direct development vs indirect development - Answers No larval stage between embryonic stage and adult stage in direct development (e.g. humans) indirect development (e.g. caterpillar / butterfly) Do complex structures evolve in a series of steps or one big step? What is an example of gradual modification? - Answers Could be both. The evolution of the eye had a series of intermediate steps Do only Hox gene groups have the homeobox region? How are Hox genes conserved? More hox genes = ? Does gene order correspond with expression within a cluster? - Answers No (e.g. sponges). Highly conserved in sequence and organization in the genome. More complexity. Yes, both spatial and developmental expression of the embryo Does diversification increase or decrease over time? When does it occur? Why? - Answers Tends to increase. often follows a decease in diversity of other groups. As groups expand their ranges, leads to new niche opportunities Does natural selection cause an increase or reduction in genetic variation - Answers Both; increase (balancing selection) decrease (positive selection, background selection Evidence for natural selection on genes. - Answers More synonymous than non-synonymous mutations; Higher substitution rates in noncoding regions evo-devo (evolutionary developmental biology) - Answers the study of evolutionary processes that shape development, thus morphological form Explain the relationship between cowbirds, botflies, and hosts - Answers Cowbirds remove botflies from host nestlings. So if there aren't botflies, the host will kick out the cowbird, but if there are botflies, the host will leave it genes normally involved in triggering of muscle contraction have evolved new sensory functions in the electric organs of two different groups of fishes. This is an example of - Answers Neofunctionalization- acquisition of a new function in a gene variant. Haeckel's biogenetic law - Answers ontogeny recapitulates phylogeny. Basically means everything follows the same series of steps and then more are added on at the end to add complexity. Rarely true Heterochrony is _______. The two types are __________ and __________. - Answers changes in timing of developmental events. Paedomorphis (neoteny)- reproductive maturity coincides with juvenile form. Peramorphosis- reproductive maturity coincides with older adult form homeotic selector genes. 1. In animals 2. In plants - Answers control gene expression in different body regions, thus determine overall body plan. 1. Hox genes 2. MADS-box genes Horizontal gene transfer is more common in __________, however, there is a decent amount of __________. - Answers Prokaryotes, gene transfer from organelle to nuclear genomes How are phenotypic plasticity and devo related - Answers For something to be phenotypically plastic, changes to the developmental program have to be able to be induced How can a regulatory mutation affect spot patterns in butterflies? - Answers A mutation in the regulatory gene can block a mutation from impacting one of the spots (module)? How can you use phylogeny to determine if an organism went through a long distance dispersal event. - Answers It they live in a habitat not adjacent to the habitat of its most closely derived relative, it likely went through a jump dispersal How can you visualize gene expression? - Answers Splice a reporter gene (e.g. GFP gene) upstream of a regulatory gene, expression of regulatory gene can be detected How can you visualize protein expression - Answers proteins extracted, antibodies made from proteins, attach fluorescent stain to the antibody, antibody will attach when protein is being expressed How did the separating of continents affect dispersal. Example? - Answers Caused long distance dispersal events. Two subgroups likely will never be reintroduced. E.g. Nothofagus has populations in Australia, NZ, and South Africa How do you recognize retrotransposed genes? - Answers They lack introns How does phylogeopgraphy relate to dispersal of humans? - Answers We can create a general timeline for when people dispersed from Africa to the rest of the world. Hox genes code for _____________ that control the _______________ that produce the characteristic structures of each ____________. - Answers Transcription factors; expression of genes; body region If lineages undergo periods of rapid change and then periods of no change, this would support the idea of __________. - Answers Punctuated equilibrium Important questions in evo-devo?* - Answers 1. How do developmental differences shape the morphological diversity 2.What is the genetic basis for devo 3. What evolutionary processes lead to these differences In evo devo, heterotropy is ___________ and individualization is ___________. - Answers changes in position (eg roots growing on stems) ; diversification of modules (e.g. diversification of vertebrate teeth In general, how do novel traits arise? - Answers Changes in regulatory networks. Mutations in regulatory genes or their targets Is gene number related to genome size? - Answers In small genomes, the correlation is highly linear. However, this falls off as the genomes increase in size; larger % of non-coding regions Is the environment the only reason a species has the features it does? - Answers No sir. The ancestry is also important MADS-box genes control ___________ and ____________ in plants. The difference between MADS-box and Hox genes are MADS-box are ____________. - Answers Growth initiation /dormancy and development of flower structures. MADS-box genes are not phylogenetically homologous. Molecular signature of natural selection - Answers In the absence of natural selection, evolution is shaped by mutation and genetic drift Most common mechanism for new genes in 1. prokaryotes 2. Eukaryotes - Answers 1. horizontal gene transfer 2. gene duplication (unequal crossing over) Mutations in the Hox genes are called __________. These can result in _________. - Answers Homeotic mutations. dramatic changes in form, often the replacement of one structure with another. Nonfunctional genes that have common ancestry with functional genes. Characteristics - Answers pseudogenes. Full of disabling mutations, can't be transcribed or translated Nuclear-organelle genome conflict - Answers Conflict between genes in nucleus and mitochondria. Eg. gene mutation in mitochondria suppresses stamen development in plants retrotranposition. Example? - Answers retrotransposons are transcribed into mRNA then reverse transcribed into DNA, which is then inserted somewhere else in the genome. Very common in Drosophila sexually antagonistic selection - Answers As one parent invests more in the offspring, the other parent invests less Stabilizing selection, genetic constraints, and ephermal divergence are all hypotheses for _____________? - Answers Why there is stasis Subfunctionalization: ___________. Example? - Answers Specialization of existing function. Hox genes in zebrafish. Each copy of original lost a different regulatory region Switching antennae for legs or having two thoraxes is likely the result of an ___________. - Answers Homeotic mutation The evolution of the forelimb in birds, false thumbs in pandas and moles, and elongated tongue of a salamander are all examples of ______________. - Answers Modification of existing features for new function The evolution of virulence - Answers Rabbit problem in Australia. Introduces virus. Rabbits slowly became less and less susceptible. The more they were exposed the more resistant they became. Best strategy for virus was intermediate virulence. The first amneotic egg is an example of a ________. This arose from one of the three ways for such structures to arise _______, ________, and _________. - Answers novel structure. modification of existing features, duplication and diversification of features, de novo The leaf tailed gecko is an example of ____________. - Answers Crypsis, looks like the leaf it lives on. The preference of two different mosquitos is an example of what? - Answers Evolution of gene expression, urban one has olfactory receptors for humans, wild one has olfactory receptor for guinea pig. Changes in gene expression can lead to massive changes in phenotype The relationship between the limber pine and seed dispersers is an example of ____________. How did they adapt? What are some other examples - Answers Coevolution. Better defended seeds when squirrels are present. Red-billed oxpecker with cape buffalo; leaf cutter ants The speciation caused by geographical separation of a population is ___________. The disappearance of groups of a species leaving gaps in range is ___________. - Answers Vicariance; Extirpation (e.g.Saxifraga cernue (flower)) There are two broad types of mimicry. ______________ and ______________ which are ______________ and _______________, respectively. - Answers Crypsis; narrow sense mimicry; imitation of background or habitat; imitation of another species This class of genes controls the development of bilateral symmetry in flowers - Answers Class II TCP Trans vs cis regulatory changes - Answers Changes in the regulatory genes vs changes in the enhancer or repressor region of the target gene True or False: phylogenetically homologous features have the same genetic and developmental basis derived from a common ancestor - Answers Not necessarily, they are similar in form and position but may be different Two examples of cis-regulatory changes in enhancers of target genes - Answers 1.Expression of pigment in drosophila 2. Expression of Pitx1 in sticklebacks two species, both with defenses imitate one another. This is known as ____________. Example? - Answers Mullerian mimicry. Heliconius spp. What are 3 specific examples for how polyploidy and hybridization affect speciation? - Answers Tragopogon (flower)- allows hybrid to become viable in a single step Achillea (white flower)- reproductively isolated and diverge from parent species Sunflowers- hybrids able to survive in specialized habitats What are exons and how do they relate to evolution? - Answers Loss, rearrangement of exons can result new portions of the genome being transcribed and expressed. A single gene can make multiple different gene products What are integral parts of the theory of mimicry? - Answers Important: 1. There is a cost to the prey to educate the predator, only works if the predator can learn and adapt. 2. Two species that look alike are more likely to have an evolutionary advantage. 3. If the mimic gets too common, the model must evolve a new trait because there is a weak defense response. What are reporter constructs used for? - Answers To determine transcription patterns of regulatory DNA regions What are the ABCDE genes? Explain the entire example - Answers They are MADS-box genes in flowers. The are expressed sequentially and from the outside to the inside of the flower. E-class genes code for whether a stem can produce flowers.