AP Biology

Learn about the chemistry of life in unit 1 of the AP Biology course. We'll cover topics such as the structure of water, hydrogen bonding, elements of life, biological macromolecules, and nucleic acids. Prepare for the exam with these resources and you be on your way to crush the AP Bio exam!

Unit 1 – Chemistry of Life

Unit 2 of AP Biology covers cell structure and function. We'll go over key topics such as subcellular components, cell size, plasma membranes, membrane permeability, membrane transport, facilitated diffusion, tonicity, osmoregulation, and cell compartmentalization. 

Unit 2 – Cell Structure & Function

Unit 3 of AP Biology is all about cellular energetics. Review topics such as enzyme structure, enzyme catalysis, environmental impacts on enzyme function, cellular energy, and photosynthesis. 

Unit 3 – Cellular Energetics

Learn about how cells communicate and reproduce in unit 4 of AP Biology. Our study guides for unit 4 cover cell communication, signal transduction, changes in signal transduction pathways, feedback, cell cycle basics, and regulation of the cell cycle. 

Unit 4 – Cell Communication & Cell Cycle

Get a solid understanding of heredity in unit 5 of the AP Biology exam. We'll cover topics such as meiosis, genetic diversity, mendelian genetics, non-mendelian genetics, environmental effects on phenotype, and chromosomal inheritance. 

Unit 5 – Heredity

Join us in exploring gene expression and regulation for the AP Biology exam. We'll cover all the topics in unit 6, such as DNA and RNA structure, replication, transcription, RNA processing, translation, regulation of gene representation, cell specialization, mutations, and biotechnology. 

Unit 6 – Gene Expression & Regulation

Understanding natural selection is crucial to learning about how ecosystems function. Learn about unit 7 of AP Biology as we cover topics such as artificial selection, population genetics, hardy-weinberg equilibrium, evidence of evolution, common ancestry, continuing evolution, phylogeny, speciation, extinction, and origin of life on earth. 

Unit 7 – Natural Selection

Ecology is all about the interactions that organisms have amongst themselves and with their environment. In unit 8 of AP Biology, we'll cover topics such as responses to the environment, energy flow, population ecology, the effect of density of populations, community ecology, etc. 

Unit 8 – Ecology

Frequently Asked Questions

The home for AP Biology reviews (including labs) as well as study strategies specific to AP Bio. You'll surely find a general resource that will improve your test-taking skills and help prepare for the exam.

General Review

Get ready to ace the multiple-choice questions of the AP Biology exam. We'll go over how the MCQs are structured, how to approach each question, and some last minute tips. By knowing the question types and the skills accessed, you'll be prepared in no time!

Multiple Choice Questions (MCQ)

Learn how to effectively answer free response questions for the AP Biology exam. We'll breakdown the FRQs and go over strategies on how to ace them. You'll be prepared with sample FRQ review videos, slides, and study guides! 

Free Response Questions (FRQ)

Get the answers to your questions from these AP Biology question and answer sessions. You'll be able to get rid of any uncertainties and feel more confident about the exam!

Q & A sessions

Get a comprehensive review of the AP Biology course. Learn every concept and unit to refresh your mind or even cram. These big reviews will serve as the ultimate preparation for the AP Biology exam. You'll feel ready for anything the test gives you and ace it in no time!

Big Reviews: Finals & Exam Prep

AP Cram Sessions 2021

Live Cram Sessions 2020

Big Idea #1: Evolution

Big Idea #2: Cellular Processes

Big Idea #3: Genetics and Information Transfer

Big Idea #4: Interactions

Live Cram Sessions 2019

Exam Reviews 2020

2019 Reviews

Water

Macromolecules

Unit 1 Overview: Chemistry of Life

Water Molecules 💧

Hydrogen Bonding 

Properties of Water 

Structure of Water and Hydrogen Bonding

Atoms

Isotopes

Electron Shells

Elemental Building Blocks 

Functional Groups

Elements of Life

Chemical Bonds

Metallic Bonds

Polymers and Monomers

Covalent Bonds

Dehydration Synthesis & Hydrolysis

Introduction to Biological Macromolecules

Carbohydrates 

Lipids

Saturated and Unsaturated Fatty Acids

Phospholipids 

Steroids

Proteins

Nucleic Acids

Big Fat Summary

Properties of Biological Macromolecules

Four Types of Macromolecules: A Refresher

Structure Determines Function

🧬 Nucleic Acids

🥩 Proteins

🍩 Carbohydrates

Other Things of Notable Importance

More About Carbs: Disaccharides and Polysaccharides

Structure and Function of Biological Macromolecules

Deoxyribonucleic Acid

Purines and Pyrimidines

Chargaff’s Rule

Example (with Arithmetic)

DNA vs. RNA

Multiple Choice Practice for Chemistry of Life

Multiple Choice Questions

Answers and Review for Multiple Choice Practice on Chemistry of Life

MC Answers and Review


Subcellular and Organelle Components

Cell Size

Plasma Membrane

Membrane Transport

Tonicity and Osmoregulation

Unit 2 Overview: Cell Structure and Function

Subcomponents

Nucleus

Ribosomes

Endoplasmic Reticulum

The Golgi Apparatus

Mitochondria

Lysosomes

Vacuoles

Chloroplast

Centrioles

Plant Cells vs. Animal Cells

Cell Structure: Subcellular Components

Cell Compartmentalization

Internal Membranes


Endosymbiotic Theory

Prokaryotic Cells

Evidence

Origins of Cell Compartmentalization

Multiple Choice Practice for Cell Structure and Function Concepts

Multiple  Choice Questions

Answers and Review for Multiple Choice Practice on Cell Structure and Function

Cell Structure & Function

Lysosome

Cell Structure and Function

Comparative Cell Size 

Plasma Membranes

Membrane Permeability

Diffusion Across the Plasma Membrane

Cell Walls

Different Modes of Membrane Transport

dMembrane Transport

When and Why Does Facilitated Diffusion Occur?

Channel Proteins 

Carrier Proteins 

Active Transport

Facilitated Diffusion

Tonicity & Osmoregulation

Osmosis

Water Potential

Public Transit... in Cells?

Passive Transport

Endocytosis

Exocytosis

Practice Problems

Answers

Mechanisms of Transport

Cells Require Energy?!

3.1 - 3.3 Enzymes

3.4 Energy

3.5 Photosynthesis 

3.6 Cellular Respiration and Fermentation

3.7 Fitness

Major Formulas

Unit 3 Overview: Cellular Energetics

Shape of Enzymes

Active Site 

Induced Fit

Enzyme Structure

Remember… Constant Energy Input!

Hold up! What is Catalysis?

How Does This Relate to Enzymes?

Competitive and Noncompetitive Inhibitors

Test Your Knowledge

Enzyme Catalysis

Temperature

Concentration

Inhibitors

Environmental Impacts on Enzyme Function

Meet Adenosine Triphosphate!

Order & Entropy

Energy & Metabolism

Cellular Energy

Light-Dependent Reactions (Electron Transport Chain)

Light-Independent Reactions (Calvin Cycle)

Summary

Photosynthesis

Glycolysis

Krebs Cycle

Electron Transport Chain

Fermentation

Cellular Respiration

Big Idea: Variation = Yay!

Example 1: Phospholipids

Example 2: Hemoglobin

Example 4: Chlorophyll

Fitness

Multiple Choice Practice for Cellular Energetics

Answers and Review for Multiple Choice Practice on Cellular Energetics

Intro to Unit 4

Before we begin…

4.1 Cell Communication

4.2 Introduction to Signal Transduction

4.3 Signal Transduction

4.4 Changes in Signal Transduction Pathway

4.5 Homeostasis and Feedback Loops

4.6 Cell Cycle

4.7 Regulation of Cell Cycle

Important Vocabulary 

Unit 4 Overview: Cell Communication and Cell Cycle

Juxtacrine Signaling

Paracrine Signaling

Autocrine Signaling

Endocrine Signaling

Cell Communication

Reception

Examples of cell surface receptors

Transduction

Phosphorylation

Amplification

Transduction has a link to evolution

Response

Special Cases

Lipid Hormones

Introduction to Signal Transduction

Environmental Impacts on Enzyme Function - Slides

Environmental Impacts on Enzyme Function - Slides

AP Biology 🧬

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