This outline lists the major concepts in the AP curriculum.
If you’re using this for review for the AP Biology exam, you should know that the AP Biology exam is oriented toward data and scenario analysis, and much less about memorization of content. But the more biology you know, the better you’ll be at generating the kinds of explanations required for the FRQ portion of the test, and the better you’ll understand the questions you’ll be posed on the multiple choice portion.
In addition to what’s below, you should do the following:
- Study every past FRQ that you can get your hands on. These are materials that belong to the College Board, and this page is a great place to start.
- Take as many past AP tests as you can. These tests are secure, which means that they’re not online, and you’ll have to get these from your teacher during in-class review. The more of these tests you take, the better you’ll be prepared for the actual test in May.
- Use my Biomania tests. You can access these at this page, or through the Biomania app.
The AP test has a math section, and math is embedded into both the M.C. and FRQ sections. You don’t need to memorize any formulas, but experience with the methods listed below will be helpful.
- χ2 (pronounced “Kai square”): it’s a key statistical test used in genetics),
- Standard error
- Calculating recombination frequencies
- Hardy Weinberg problems.
Mr. W’s 2019 AP Bio Content Review Outline
Be able to define and explain all the terms below. If there are embedded questions, be able to answer them. Links take you to tutorials and/or songs. All links open in a separate tab.
1. Scientific Method
- What’s the difference between a control group and an experimental group?
- Compare and contrast Independent and a dependent variable?
- In a two axis graph, where does each variable go?
Be able to answer/explain the following:
- Explain Darwin’s idea of natural selection. Use this reading if you need a review of this idea (probably the most important idea in biology). It’s followed by a set of flashcards. You can also use this tutorial, which presents natural selection in the context of population genetics.
- Describe the three types of selection (directional stabilizing, disruptive). See the preceding link for a tutorial.
- What’s the evidence for evolution? (You should be able to talk about fossils; anatomical homologies; analogies; embryology; molecular homologies, modern examples of evolution in insects, bacteria, viruses, etc. In terms of resources look at this worksheet.
Note: Population genetics and speciation are listed below.
3. Basic Chemistry
(Note that you won’t be explicitly tested on this, but it’s assumed that you’re familiar with what follows. It’s very common for AP questions to include information about use of radioactive isotopes for tracing respiration, photosynthesis, or other cellular processes, for example). If you need a refresher on basic chemistry, follow this link.
- Ionic v covalent bonds
4. Properties of water relevant for life
Again, this probably won’t be directly tested, but you would need to be able to talk about hydrogen bonding to be able to explain a process like transpiration.
On a general level, you should be able to answer these questions:
5 and 6: Biochemistry
Note: almost all of this material, except for proteins, won’t be directly tested on the AP exam).
- Note: don’t bother learning the names of the functional groups, but you should know that…
- Functional groups differ in terms of polarity, acidity, etc.
- Amino acids differ because of the functional groups attached to their R groups
- Protein secondary structure involved H bonding between carboxyl and amino groups in polypeptide backbone
- Monomers and polymers
- Carbohydrates (Mono, di, polysaccharides)
- Lipids (Saturated vs. mono/polyunsaturated, importance of cholesterol; structure of phospholipids).
- Proteins (note: this is the part of biochemistry that you need to know well)
- Describe the basic structure of amino acids. Discuss how amino acids differ from one another)
- Describe the four levels of protein structure
- Primary structure and directionality (example: enzymes that degrade proteins can work from the N terminus or the C terminus, but not both)
- Explain the molecular cause of sickle cell disease.
- Note: don’t bother learning the names of the functional groups, but you should know that…
Note: Nucleic Acids are covered under “molecular genetics” below.
7. Cell Structure
Here’s the link to the main menu of my cell structure and function tutorials. Specific tutorials are linked below.
- Why are cells small? I have a video lecture about this, and a tutorial.
- Be able to calculate surface area/volume ratios (formulas will be provided).
- Describe the differences between prokaryotic and eukaryotic cells.
- Eukaryotic cell structure (lots of interactive tutorials)
- Differentiate between plant cells and animal cells: You use my My Cell Song to review.
- Explain the evolutionary advantage of eukaryotic cells’ division into compartments.
- Endomembrane system: What is it? What cell parts are involved? What’s their role in processes such as intracellular digestion, lysosome formation, endocytosis, and exocytosis?
- Explain the origins of eukaryotic cells, and provide evidence for the endosymbiotic origins of mitochondria and chloroplasts.
8. Cell Membrane structure
I cover most of what you need to know about membranes in this series of tutorials. Be able to:
- Describe the structure of phospholipids, and explain how phospholipid bilayers form.
- Describe the fluid mosaic model, and the structural and functional role of membrane proteins, phospholipids, cholesterol
- Explain the meaning of selective permeability. Describe how different classes of substances (polar/nonpolar, large, small) move across membranes
- Compare active and passive transport, simple diffusion and facilitated diffusion
- Explain the importance of active transport in setting up nerve impulse transmission (Na+/K+ pump), and ATP synthesis (proton pumps).
- How do plant cells use proton pumps to move ions such as potassium and chlorine up a concentration gradients).
- Compare hyper/hypotonic solutions, and their behavior in relation to membranes. My Osmosis Rap video and these tutorials cover a lot of this.
- Describe water potential (know how to use the two equations, which you’ll be provided with on the AP exam formula sheet. Here’s a tutorial that covers the first one).
- Compare and contrast endocytosis, exocytosis.
9. Energy and Enzymes
- What is entropy? Why is it such an important concept in biology?
- What is (Gibbs) free energy? Connect the idea of free energy to what happens in photosynthesis and cellular respiration.
- Compare and contrast endergonic and exergonic reactions, and give examples of each.
- What is activation energy?
- Describe the basic features of enzymes. Your answer should include the type of molecule they are, their active site, allosteric sites, and the relationship between enzymes and activation energy.
- Explain how enzymes work. You answer should include the lock and key and induced fit models, and should explain why enzymes are specific.
- Explain how enzymes respond to changes in their environment (their response to heat, pH, saturation, and explain why enzymes respond in this way).
- Explain how enzymes are regulated (especially allosteric feedback, competitive and non-competitive inhibition). Here’s a link to a tutorial about this.
10. Cell Respiration:
I have tutorials covering cellular respiration.
- Describe the ATP/ADP cycle.
- Explain the importance of phosphorylation in biological processes (and list a few examples)
- What’s the function of the mitochondria. Explain how the structure of mitochondria makes cellular respiration possible.
- What’s the difference between substrate level oxidative phosphorylation (and how is this different from photophosphorylation)?
- What are the key reactions involved involved in cellular respiration. Keep your description confined to the big picture only: what goes in, what goes out). The links below are mostly to music videos, and there’s a full set of tutorials available.
- Glycolysis (songs for this and the two below. The tutorial is linked above.
- Krebs cycle (What are the roles of oxaloacetate, acetyl Co-A, ATP, FADH2, and NADH).
- Electron transport chain and chemiosmosis (and be able to relate this to mitochondrial structure and function)
- Fermentation (link is to a tutorial)
11. Cell Communication
I have a complete tutorial about G protein coupled receptors (which are essential in understanding how hormones like epinephrine or glucagon work). Be able to explain the essential structure and function of each of the following:
- Ligands: What are they? What are some examples? How do they interact with their receptors?
- Explain the structure of a G protein linked receptor.
- What are second messengers? What are the most common ones? What do they do?
- What are signal transduction pathways?
- How do signal transduction pathways amplify cellular responses?
- What are the differences between the mechanisms involved in steroid and protein hormones?
- What is apoptosis (and why is it important)? Describe one mechanism by which apoptosis works.
- Cell communication is a central biological process. How is it important in hormone action? Development? The immune system? Communication between neurons?
12. Cellular Reproduction and the Eukaryotic Cell Cycle
I have a series of quizzes, some in tutorial format. Because you ultimately have to know them for meiosis, I do teach the names of the phases — prophase, metaphase, etc. — but there won’t be any questions about naming phases on the AP exam). Here are the key ideas.
- Describe how cell division in occurs prokaryotes. Not that the term binary fission is a necessary term for answering, but you should elaborate about the mechanism).
- Describe/define the following: chromosome, chromatid, chromatin, centromeres, kinetochores
- Describe the Eukaryotic cell cycle (Note that this is not the phases of mitosis, but the cycle that includes G1, S, G2, M).
- Describe what happens during mitosis (don’t worry about the phases, but you should be able to describe this in terms of replication, alignment, and separation).
- What’s the G0 phase? What’s the relationship between this phase and cell specialization.
- How is the cell cycle controlled? (Your answer should include checkpoints/cyclins/cyclin dependent kinases).
- What are some of the ways in which cancer cells don’t obey the rules that govern cell division in other cells?
13. Molecular Genetics
- What is the central dogma of molecular genetics?
- Describe the steps leading to the discovery of DNA’s structure. Your answer should involved the key conceptual moves and contributions of Watson and Crick, Wilkins and Franklin; Avery, MacCleod and McCarty; Hershey and Chase; and Griffith’s Transforming Factor. Note that you don’t need to know the names of the researchers, but be able to explain the experiments themselves. You can consult my handout about this.
- Describe DNA’s Structure (I have music video and tutorials covering this)
- What are the monomers of DNA? The backbone? The base pair bonding rules?
- DNA has directionality (5’ and 3’ ends). What does this mean, and why is this significant?
- How is DNA replicated? This has two aspects:
- Meselson and Stahl conducted an experiment using radioactive isotopes that established that DNA is replicated semi-conservatively. Explain 1) what the semiconservative model is, and 2, how they proved that it was correct (as opposed to the dispersive or conservative models.
- Explain how a team of enzymes (including helicase, primase, DNA polymerase, ligase, leading v. lagging strands, etc.) work together to copy DNA. Note that I also have a music video about this…(set to a Salsa tune. The animations should prove helpful).
- What are the key steps involved in transcription? You can consult my basic tutorial here, or a more complex one (including transcription factors and control elements) here. In your explanation, include the:
- Role of the promoter, structural genes, terminators.
- Introns and RNA processing in eukaryotes.
- Translation/protein synthesis. See my tutorial about this, and my Protein Synthesis Song)
- Explain how mRNA is translated into protein: Include codons, roles of ribosomes, various RNAs, release factor, etc.
- Know how to use a genetic code table, and be able to translate any given string of RNA or DNA into amino acid sequences.
- Explain protein targeting: In other words, how do proteins “know” where to be made? Your answer should include a discussion of signal peptides, signal recognition particles, and bound or free ribosomes)
- Mutations (types and effects). I cover this is a fairly general way in the first section of a tutorial that’s in my population genetics module). In addition, you should be able to
- Explain what silent mutations are (and compare them to active ones)
- Describe what frameshift mutations are (and explain how they’re caused by deletions and insertions).
- Explain the evolutionary importance of mutation.
16. Bacteria and Viruses
- Describe the basic structure of a virus.
- Explain how viruses are like organisms, but also not like organisms.
- Compare and contrast the lytic and lysogenic cycles.
- Describe the life cycle of a retrovirus.
- Describe the effect of HIV on the immune system.
- Describe how variation in viral population is generated? Why is this important?
- How do viruses introduce variation into their hosts/prey?
- Bacteria reproduce through binary fission. Yet, there’s a lot of genetic diversity within bacterial populations. What are the sources of this genetic diversity in bacterial populations? Your answer should include descriptions of transposons, conjugation, transformation, transduction, and mutation
- What is horizontal gene exchange in bacteria? How does it explain phenomena like the spread of antibiotic resistance?
- Describe regulation of gene expression in bacteria (which means being able to explain the tryp and lac operons). I cover operons in this tutorial.
17. DNA technology/Genetic Engineering
I have a whole series of genetic engineering tutorials that explain the biology behind the techniques below. Understanding the underlying biology behind these technologies is probably going to be useful on both parts of the exam (but you probably won’t be asked for explicit knowledge about any of them).
- Use of plasmids for genetic engineering (explaining the science behind the pGLO lab, for example)
- DNA fingerprinting/profiling (Restriction endonucleases, RFLPs, gel electrophoresis)
- DNA sequencing (Sanger sequencing)
- Gene Editing using CRISPR-Cas9
- Benefits of transgenic organisms.
- Problems associated with genetic engineering, especially in agriculture.
- What’s the difference between diploid v. haploid cells?
- What are homologous chromosomes?
- What happens during meiosis (the names of the phases are are not particularly important, but I find it hard to talk about meiosis without talking about the phases. The key point is to be able to explain the transition from diploid to haploid cells and from doubled to single chromosomes.
- Describe how meiosis creates for variation in offspring. Your answer should include crossing over independent assortment.
- Explain the evolutionary importance of meiosis
- Describe how chromosomal mutations/ abnormalities can come about by nondisjunction. You can use Down, Turner, or Klinefelter syndrome as illustrative examples.
19. Genetics (Mendelian and Post Mendelian)
I have a series of of tutorials that covers much of what’s below (except for dihybrid crosses, autosomal linkage, crossing over, and calculating recombination frequencies.
- Be able to define these key terms: gene, allele, phenotype, genotype, dominant, recessive.
- Be able to solve monohybrid and dihybrid crosses.
- Being able to use rules of probability (rules of multiplication, addition) to make predictions about various crosses.
- Describe the following post-Mendelian genetic phenomena: codominance, multiple alleles, blood type inheritance (ABO system); mitochondrial inheritance (only through mother)
- Contrast autosomal inheritance with the inheritance of sex-linked alleles.
- Explain crossing over, and how recombination frequencies can be used to create linkage maps.
- Be able to solve problems related to recombination frequencies in the fruit fly drosophila and in the fungus Sordaria
20. Population genetics
I have a series of tutorials that covers all the population genetics you’ll need to know. You should be able to
- Explain evolution as a change in allele frequencies
- Use the Hardy Weinberg equation to calculate the frequencies of alleles in a population when given the frequencies of various phenotypes or genotypes within that population.
- Describe the five conditions under which populations remain in genetic equilibrium.
- Explain and identify specific population genetic phenomena like genetic drift, population bottlenecks, founder effect, heterozygote advantage
I cover speciation in this series of tutorials. You should be able to
- Describe the major types of reproductive isolating mechanisms (pre and post zygotic)
- Explain the allopatric model of speciation.
- Describe various mechanisms behind sympatric speciation (such as polyploidy in plants; habitat isolation and sexual selection in animals.
22. Origin and early evolution of life
My series of tutorials on the origin and early evolution of life goes into much more detail than what’s needed. For the purposes of the AP exam, you should probably be able to do the following:
- Explain the origin of monomers (Miller-Urey experiment)
- Describe some scenarios for the origins of polymers and protobionts,
- The RNA world is a widely quoted scenario for the origin of life. What is this idea? Why is RNA a better candidate for being the first genetic molecule than DNA.
- LUCA stands for last universal common ancestor. What’s the evidence for their having been a single LUCA? List and describe some of LUCA’s traits (try to think of about five).
- Explain and describe the evidence for for a single ancestry of eukaryotes (which amounts to explaining the endosymbiotic hypothesis).
- Though this doesn’t neatly fall into the origin of life, a related topic has to do with Earth history: Explain the importance of mass extinctions and subsequent adaptive radiations in the history of life.
You should be able to understand the working of phylogenetic trees. This includes
- Constructing a phylogenetic tree from a character table.
- Analyze a phylogenetic tree to
- Identify organisms that are most closely related.
- Identify shared characteristics that indicate common ancestry
24. Eukaryotic Chromosomes and Gene Regulation
My tutorials about Eukaryotic gene regulation tell you everything you need to know. Be able to explain/answer the following:
- What’s the difference between euchromatin and heterochromatin, and how does this explain how genes are expressed in cells?
- What’s the connection between DNA packaging (though histones, methylation, and acetylation) and gene expression?
- How are genes activated and deactivated through the action of DNA regulatory sequences, transcription factors (which can be activators or repressors), small regulatory RNAs.
- What are some post transcriptional processes related to gene expression and regulation. Your answer should include the terms introns, exons, etc.
- What are some regulatory processes that occur before, during, and after translation?
- What is epigenetics? List some examples.
A related topic is cancer
- What is the difference between oncogenes and tumor suppressor genes?
25. Animal Development
My tutorials on Animal Development cover everything below
- It’s useful to know the key events in early development (though you won’t be explicitly tested on this). These include fertilization, which leads to cleavage, which leads to gastrulation, and finally organogenesis (such as nervous system development).
- “All cells are genomically equivalent.” Explain what this statement means, and why genomic equivalence is an important principle in understanding development.
- What are cytoplasmic determinants, and how do they influence early development?
- What’s the difference between determination and differentiation?
- What is induction? How does it work?
- Describe how morphogenic gradients and positional information can lead to the emergence of the three dimensional form of a developing embryo.
- What is apoptosis? How does it work and why is it important in development?
- What are homeotic genes?
- Experiments related to induction (transplantation of tissue leading to induction of differentiation) seem to show up a lot on the AP Bio exam. Know, for example, about Spemann and Mangold’s organizer experiment.
26. Animal Biology 1: Homeostasis and Regulation
This topic covers negative and positive feedback systems in animals. The key theme is maintenance of homeostasis. I have a series of tutorials about animal homeostasis that address the questions/topics below.
- What is homeostasis?
- How does negative feedback work? Give examples.
- What is positive feedback (and describe how that works)?
- How are regulators different from conformers?
- What are the main mechanisms of thermoregulation?
- How do humans (and our animal relatives) regulate blood sugar levels? In your answer, you should mostly focus on explaining the insulin/glucagon system?
- What are two types of diabetes, and what are their causes?
- How do humans (and our animals) osmoregulate? This mostly involves explaining what happens in the collecting duct of the nephron as it responds to ADH.
27. Immune System
My tutorials on the immune system cover everything you need to know. Be able to explain.
- What are the three levels of defense that we have against infectious pathogens.
- Describe the innate immune response (which I also cover in this music video)
- How does the specific immune response work? Your response should involved how antigens are recognized, overcome, and remembered (and I have a music video that explains pretty much everything you need to know).
- How is the humoral response different from the cell-mediated response? In your answer, describe the workings of both systems.
- How do vaccines work?
- Compare and contrast passive and active immunity.
28. Neurons and the Nervous System
My tutorials on the nervous system cover everything you’ll need to know. You should be able to respond to the following questions.
- Describe the structure of a reflex arc (sensory neurons, interneurons motor neurons,)
- Describe the structure and function of the neuron (including dendrites, cell body, axons)
- Explain how nerve impulse transmission works.This should include
- How is the resting potential generated?
- What happens during an action potential?
- What is saltatory conduction (and why is it important).
- What happens at a synapse to enable a nerve impulse to move from a neuron to its target (another neuron, a muscle, or a gland)?
- Compare the way neuron signalling works to how
29. Animal Behavior
It’s very hard to advise you about how to review for this topic. I’m pretty certain that nothing on the list below will be explicitly on the AP exam test. At the same time, it’s completely possible that you might be asked to look at a data set related to animal behavior, and interpret it.
The one thing you might want to explore in a bit more detail are the two last items in this list, which relate to the timing of behavior caused by internal rhythms (such as circadian rhythms) or other environmental cues.
- What’s the difference between innate vs. learned behavior? What are the evolutionary benefits (and drawbacks) associated with each?
- Describe fixed action patterns.
- Describe various types of learning, including
- classical and operant conditioning
- observational learning
- Describe various types of movement: kinesis v. taxis, migration
- How does the idea of an optimal foraging strategy related to the idea that animal behavior has been programmed by natural selection?
- Describe and explain the following social interactions: agonistic interactions, dominance hierarchies, territoriality, altruism (predator warnings), inclusive fitness, reciprocal altruism, herding, flocking.
- Describe and explain some of the ways that animals communicate, including pheromones and honeybee dances.
- Explain how animals respond to environmental cues, resulting in behaviors like estivation, hibernation, and migration.
- Explain how the behavior of animals can be regulated by circadian rhythms and biological clocks.
I have a complete set of photosynthesis tutorials that cover pretty much everything you need to know. For a blast from the past, you can watch my first YouTube videos ever (the first one is mostly the light reactions, the second mostly the Calvin cycle) . But I also have three much better videos about the light reactions
You should be able to answer/explain the following:
- How does the structure of a chloroplast lend itself to performing its function? in responding to this, focus mostly on the light reactions.
- Describe, in a big picture way, what happens during photosynthesis. What are the two phases? For each one, what goes in? What comes out?
- Explain what happens during the light reactions. You answer should include the Z scheme, the generation of electron flow, and the chemiosmotic photophosphorylation of ADP to create ADP.
- Compare and contrast cyclic and non-cyclic electron flow.
- Explain what happens during the Calvin cycle.
- How are the reactions of photosynthesis complementary to those involved in cellular respiration?
31. Plant responses to light
32. Water Movement in plants
I cover this in a series of plant water transport tutorials. You should be able to answer/respond to the following:
- Explain how water potential works. That includes being able to explain the general concept of how water moves in response to water potential gradients, as well as explaining the key components of water potential (solute and pressure) and how they affect water potential.
- Describe the key structures of vascular tissue in plants, and how that structure enables plants to conduct water up from their roots to the their shoots. What you’re doing here is relating the structure of the xylem to the adhesive and cohesive forces connected to transpiration.
- Describe the cohesion-transpiration-tension model of upward water flow in plants.
- Describe how various environmental conditions increase or decrease the rate of transpiration in a plant.(effect of heat, humidity, light, and wind).
- Explain how plants control rates of transpiration through stomata
33. Population Ecology
- Describe some of the key components of population. Your answer should include a description of population size, density, dispersion patterns, age structure, and survivorship curves).
- Compare and contrast the exponential and logistic models of population growth. Your answer should include carrying capacity and types of limiting factors (density dependent and density independent)
- What are the characteristics of r and K selected species?
34. Community Ecology
- What is coevolution?
- What are some of the key adaptations that evolve in predators and prey.
- Describe the competitive exclusion principle, and explain how competition can lead to resource partitioning and character displacement. In you explanation, provide specific examples.
- What is a niche? How is species’ realized niche different from its fundamental niche. Summarize how this has been experimentally demonstrated with barnacle species.
- What are the three different types of of symbiosis? Provide examples of each, and use the symbols +, – and 0 to characterize the relationships.
- Explain the importance of keystone species, and how that concept relates to the idea of a trophic cascade.
- What is ecological succession. Describe the difference between primary and secondary succession.
- What is the relationship between community biodiversity and resilience? Why?
35. Ecosystem Structure
I have interactive tutorials that cover the carbon and nitrogen cycles. The carbon cycle tutotorial includes my a Carbon Cycle song. Another series of tutorials cover food webs, food chains, and and the idea of trophic levels. Trophic levels and the 10% rule are also covered in my Food Chain Song!
Your understanding of ecology should enable you to understand the following:
- Describe the key features of any biogeochemical cycle (which should include the idea of reservoirs and fluxes).
- Explain the flow of matter in the carbon and the nitrogen cycles.
- Explain food chains and food webs, and how the two are interrelated.
- Compare and contrast primary and net ecosystem productivity?
- What are trophic levels? How much energy is passed between trophic levels, and why? Connect what’s happening between trophic levels to the idea of free energy and the law of conservation of energy.
- Ecological Pyramid are used to represent ecosystem structure. Describe and explain the pyramids of energy, of biomass, and of numbers.
36. Ecosystem Disturbance (by humans)
- Describe several ways that humans are having a negative impact on planetary biodiversity. Your explanation should include:
- Habitat destruction
- Habitat fragmentation
- Introduced species
- Invasive species
- Explain the relationship between biodiversity and resilience, on both a population and ecosystem level.
- Explain why artificial ecosystems often lack diversity, and have little resilience. Use this as a way to explain problems with genetically engineered crops, or monocultures in general.
- Describe several ways that humans are having a negative impact on planetary biodiversity. Your explanation should include:
- back to the AP Bio Review Menu