1Define virus.
A nonliving infectious particle made of genetic material inside a protein coat that must infect a living cell to reproduce.
2Define host.
The organism a virus infects and uses for resources to replicate.
3Describe the physical and physiological connections between hosts and viruses.
Viruses attach to host receptors, inject genetic material, use host machinery, and assemble new virions.
4Defend a virus being a living organism.
Viruses contain genes, evolve, and reproduce within cells.
5Defend a virus not being a living organism.
They lack cells, do not use energy or grow, and cannot reproduce without a host.
6List characteristics that define a living organism.
Order, response to stimuli, reproduction, growth, regulation, energy use, adaptation, evolution.
7Describe the ecosystems in which viruses thrive.
Anywhere hosts are found—oceans, soil, plants, animals, bacteria, extreme environments.
8Define types of symbioses.
Commensalism (one benefits, one unaffected), mutualism (both benefit), parasitism (one benefits, one harmed).
9Identify what role viruses fit into regarding symbioses.
Viruses act as parasites.
10Discuss the role of viruses in an ecosystem.
They control populations, recycle nutrients, and influence evolution.
11Discuss how climate change impacts the geographic distribution of viruses.
Warming shifts habitats and vectors, spreading viruses to new areas.
12Compare and contrast a bacterial infection and a virus.
Bacteria are living and killed by antibiotics; viruses are nonliving and require antivirals/vaccines.
13Describe selective pressures in symbiotic vs predator/prey vs competitive relationships.
Symbiosis favors cooperation, predator/prey favors defenses/hunting traits, competition favors resource acquisition.
14Connect multiple levels associated with viruses.
Viruses affect cells, individuals, populations, and ecosystems.
15Define evolution, natural selection, adaptation, fitness.
Evolution is change in traits; natural selection favors beneficial traits; adaptations are those traits; fitness is reproductive success.
16Define artificial selection.
Humans choose desired traits in organisms.
17Compare and contrast natural and artificial selection.
Natural = environment-driven; artificial = human-driven.
18Describe three principles underlying natural selection.
Variation, heritability, differential reproduction.
19Compare and contrast micro- and macro-evolution.
Micro = small changes within species; macro = large changes forming new species.
20Refute misconceptions about evolution.
Evolution has no goal, doesn’t happen to individuals, and is evidence-based.
21Define gene.
A DNA sequence that codes for a specific trait or protein.
22Define allele.
A version of a gene.
23Compare and contrast gene and allele.
A gene determines a trait; alleles are forms of that gene.
24Identify adaptations for different environments.
Traits suited to climate, food, or predators.
25Discuss the connection between natural selection and adaptation.
Natural selection produces adaptations.
26Describe five mechanisms that change allele frequencies.
Mutation, gene flow, genetic drift, natural selection, sexual selection.
27Define mutation, gene flow, genetic drift, natural selection.
Mutation adds variation; gene flow moves genes; drift changes alleles by chance; natural selection favors helpful traits.
28Identify mechanisms for allele frequency changes.
Examples include migration spreading genes or drought favoring resistant alleles.
29Define variation in a trait.
Differences among individuals.
30Define heritability.
The portion of trait variation passed to offspring.
31Identify structural, behavioral, or physiological adaptations.
Structural = body part; behavioral = action; physiological = internal process.
32Explain what phylogenetic trees represent.
Evolutionary relationships among species.
33Compare and contrast prokaryote and eukaryote.
Prokaryotes lack nucleus and organelles; eukaryotes have them.
34Compare and contrast plant and animal cells.
Plants have cell walls, chloroplasts, large vacuoles; animals do not.
35Define node, root, and tip.
Node = common ancestor; root = oldest ancestor; tip = current species.
36Define species using the biological species concept.
Organisms that interbreed to produce fertile offspring.
37Define reproductive isolation.
When species cannot interbreed due to barriers.
38List mechanisms that result in reproductive isolation.
Temporal, habitat, behavioral, mechanical, gametic, hybrid inviability.
39Group reproductive isolating mechanisms.
Prezygotic = prevent fertilization; postzygotic = prevent viable/fertile offspring.
40Provide examples of isolating mechanisms.
Temporal = different breeding times; habitat = different locations; behavioral = mating calls; etc.
41Discuss when the biological species concept doesn’t work.
Fossils and asexual species.
42Interpret phylogenetic trees.
Identify roots, branches, nodes, descendants.
43Identify ancestral vs derived traits.
Ancestral = shared and old; derived = new and unique.
44Identify monophyletic groups.
Groups with a common ancestor and all descendants.
45Identify acclimation or adaptation.
Acclimation = short-term change; adaptation = genetic.
46Identify homologous or analogous traits.
Homologous = same origin; analogous = same function, different origin.
47Compare homologous and analogous traits.
Homologous show shared ancestry; analogous show convergent evolution.
48Determine convergent evolution using a tree.
Unrelated species evolve similar traits.
49Identify closest relatives on a tree.
Those sharing the most recent common node.
50Use two ways to determine closest relatives.
Node comparisons; shared derived traits.
51Draw trees from closest-relative information.
Connect species by shared recent ancestors.
52Define terms in Fick's Law.
Gas exchange depends on surface area, distance, and concentration difference.
53Predict changes in Fick's Law terms.
More area or concentration increases diffusion; thicker membranes slow it.
54Describe adaptations maximizing gas exchange.
Large surface area, thin membranes, moist surfaces, steep gradients.
55Discuss how Influenza A affects gas exchange.
It damages alveoli, lowering surface area and diffusion efficiency.