AP Biology: Help and Review

Course Summary

Review the engaging video lessons and quizzes in this help and review course to refresh yourself on all the topics covered in your AP biology course. Our study materials can also help you prepare for the test and help you earn your best score possible on the exam.
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28 chapters in AP Biology: Help and Review

Course Practice Test

Check your knowledge of this course with a 50-question practice test.
  • Comprehensive test covering all topics
  • Detailed video explanations for wrong answers
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Course Progress Best Score
Lesson 1 - How a Phospholipid Bilayer Is Both Hydrophobic and Hydrophilic  Take Quiz
Lesson 2 - The Fluid Mosaic Model of the Cell Membrane  Take Quiz
Lesson 3 - Passive Transport in Cells: Simple and Facilitated Diffusion & Osmosis  Take Quiz
Lesson 4 - Active Transport in Cells: Definition & Examples  Take Quiz
Lesson 5 - Endocytosis and Exocytosis Across the Cell Membrane  Take Quiz
Lesson 6 - Structure of the Nucleus: Nucleolus, Nuclear Membrane, and Nuclear Pores  Take Quiz
Lesson 7 - The Ribosome: Structure, Function and Location  Take Quiz
Lesson 8 - The Endomembrane System: Functions & Components  Take Quiz
Lesson 9 - The Cytoskeleton: Microtubules and Microfilaments  Take Quiz
Lesson 10 - Mitochondria Structure: Cristae, Matrix and Inner & Outer Membrane  Take Quiz
Lesson 11 - Chloroplast Structure: Chlorophyll, Stroma, Thylakoid, and Grana  Take Quiz
Lesson 12 - Plant Cell Structures: The Cell Wall and Central Vacuole  Take Quiz
Lesson 13 - Eukaryotic and Prokaryotic Cells: Similarities and Differences  Take Quiz
Lesson 14 - Viruses: Bacteriophage Lytic and Lysogenic Cycles  Take Quiz
Lesson 15 - What is a Phospholipid? - Structure, Functions & Composition  Take Quiz
Lesson 16 - Rough Endoplasmic Reticulum: Definition, Structure & Functions  Take Quiz
Lesson 17 - Centriole: Definition, Structure & Function  Take Quiz
Lesson 18 - Depolarization: Definition & Concept  Take Quiz
Lesson 19 - Heat Shock: Method & Explanation  Take Quiz
Lesson 20 - Homology: Definition & Examples  Take Quiz
Lesson 21 - Metaphase I: Stages of Meiosis  Take Quiz
Lesson 22 - Receptor-Mediated Endocytosis: Definition & Example  Take Quiz
Lesson 23 - Smooth Endoplasmic Reticulum: Definition, Functions & Structure  Take Quiz
Lesson 24 - Triacylglycerol: Structure & Function  Take Quiz
Lesson 25 - The Difference Between Plant and Animal Cells  Take Quiz
Lesson 26 - Monerans: Definition, Examples & Types  Take Quiz
Lesson 27 - Anchorage Dependence: Definition & Overview  Take Quiz
Lesson 28 - Cell Membrane Analogies  Take Quiz
Lesson 29 - Do Red Blood Cells Have a Nucleus?  Take Quiz
Lesson 30 - Do White Blood Cells Have Nuclei?  Take Quiz
Lesson 31 - Glycoprotein Function in the Cell Membrane  Take Quiz
Lesson 32 - How Do Sugar Molecules Cross the Cell Membrane?  Take Quiz
Lesson 33 - How Does the Cell Membrane Maintain Homeostasis?  Take Quiz
Lesson 34 - Importance of Carbohydrates in the Cell Membrane  Take Quiz
Lesson 35 - Major Structural Components of the Cell Membrane  Take Quiz
Lesson 36 - Major Type of Lipid Found in the Cell Membrane  Take Quiz
Lesson 37 - Nucleus Function in Animal Cells  Take Quiz
Lesson 38 - Parts of the Cytoskeleton  Take Quiz
Lesson 39 - Proteins in the Cell Membrane  Take Quiz
Lesson 40 - What Substances Pass Through the Cell Membrane by Diffusion?  Take Quiz
Lesson 41 - The Role of the Nucleus in the Cell  Take Quiz
Lesson 42 - Do Eukaryotic Cells Have a Nucleus?  Take Quiz
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Course Progress Best Score
Lesson 1 - Classification of Vascular, Nonvascular, Monocot & Dicot Plants  Take Quiz
Lesson 2 - Structure of Plant Stems: Vascular and Ground Tissue  Take Quiz
Lesson 3 - Apical Meristem & Primary Shoot System Growth  Take Quiz
Lesson 4 - Lateral Meristem & Secondary Shoot System Growth  Take Quiz
Lesson 5 - Structure of Leaves: The Epidermis, Palisade and Spongy Layers  Take Quiz
Lesson 6 - Primary Root Tissue, Root Hairs and the Plant Vascular Cylinder  Take Quiz
Lesson 7 - Root System Growth: The Root Cap, Primary Roots & Lateral Roots  Take Quiz
Lesson 8 - Nitrogen Fixation: Significance to Plants and Humans  Take Quiz
Lesson 9 - Xylem: The Effect of Transpiration and Cohesion on Function  Take Quiz
Lesson 10 - Phloem: The Pressure Flow Hypothesis of Food Movement  Take Quiz
Lesson 11 - Flowers: Structure and Function of Male & Female Components  Take Quiz
Lesson 12 - Methods of Pollination and Flower-Pollinator Relationships  Take Quiz
Lesson 13 - Monocotyledon Plants: Examples, Definition & Pictures  Take Quiz
Lesson 14 - C3 Plants: Definition, Types & Examples  Take Quiz
Lesson 15 - Herbaceous Plants: Examples & Types  Take Quiz
Lesson 16 - NADPH: Definition, Structure & Function  Take Quiz
Lesson 17 - Nitrogenase: Structure, Role in Nitrogen Fixation & Activity  Take Quiz
Lesson 18 - Petiole: Definition & Function  Take Quiz
Lesson 19 - Phylogenetic Tree: Definition & Types  Take Quiz
Lesson 20 - Upper Epidermis of a Leaf: Function & Definition  Take Quiz
Lesson 21 - Vegetative Propagation in Plants: Definition, Methods & Examples  Take Quiz
Lesson 22 - Meristematic Tissue: Definition & Function  Take Quiz
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Course Progress Best Score
Lesson 1 - Male Reproductive System: Functions, Organs & Anatomy  Take Quiz
Lesson 2 - Male Reproductive System: Accessory Gland Functions  Take Quiz
Lesson 3 - Testicular Anatomy: Structure, Terms & Diagrams  Take Quiz
Lesson 4 - Male Reproductive System: External Anatomy  Take Quiz
Lesson 5 - Sperm's Journey from the Testes to Urethral Orifice  Take Quiz
Lesson 6 - The HPG Axis: Hormones of Male Reproduction  Take Quiz
Lesson 7 - Female Reproductive System: Internal Anatomy  Take Quiz
Lesson 8 - The Uterus and Uterine Wall: Structure and Parts  Take Quiz
Lesson 9 - External Anatomy of the Female Reproductive System  Take Quiz
Lesson 10 - HPG Axis: Hormonal Control of the Ovarian Cycle  Take Quiz
Lesson 11 - Phases of The Ovarian Cycle: Overview from Puberty to Menopause  Take Quiz
Lesson 12 - Follicular Phase of the Ovarian Cycle  Take Quiz
Lesson 13 - Luteal Phase of the Ovarian Cycle  Take Quiz
Lesson 14 - The Uterine Cycle: Phases and Endometrial Changes  Take Quiz
Lesson 15 - The Uterine Cycle: Menses  Take Quiz
Lesson 16 - The Uterine Cycle: Proliferative Phase  Take Quiz
Lesson 17 - The Uterine Cycle: Secretory Phase  Take Quiz
Lesson 18 - The Female Reproductive Axis: Coordination of the Brain, Ovaries & Uterus  Take Quiz
Lesson 19 - Ovulation to Implantation: Oocyte's Path through Uterine Tubes  Take Quiz
Lesson 20 - Absolute Refractory Period: Definition & Significance  Take Quiz
Lesson 21 - Relative Refractory Period: Definition & Significance  Take Quiz
Lesson 22 - Gonads: Definition & Function  Take Quiz
Lesson 23 - Human Chorionic Gonadotropin (HCG): Side Effects & Definition  Take Quiz
Lesson 24 - Endometrial Ablation: Procedure, Recovery & Side Effects  Take Quiz
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Course Progress Best Score
Lesson 1 - Multicellular Organisms, Tissues and Epithelium  Take Quiz
Lesson 2 - Types of Connective Tissue  Take Quiz
Lesson 3 - Skeletal System and Muscular System  Take Quiz
Lesson 4 - Circulatory System I: Types of Circulatory Systems  Take Quiz
Lesson 5 - Circulatory System II: The Human Vascular System  Take Quiz
Lesson 6 - Circulatory System III: The Heart  Take Quiz
Lesson 7 - Circulatory System IV: Red Blood Cells  Take Quiz
Lesson 8 - Circulatory System V: Hemoglobin  Take Quiz
Lesson 9 - Gas Exchange in the Human Respiratory System  Take Quiz
Lesson 10 - Digestive System I: The Upper Gastrointestinal Tract  Take Quiz
Lesson 11 - Digestive System II: The Lower Gastrointestinal Tract  Take Quiz
Lesson 12 - Excretory System  Take Quiz
Lesson 13 - Hypoglossal Nerve: Function, Palsy & Damage  Take Quiz
Lesson 14 - Mesoderm Layer: Definition, Development & Formation  Take Quiz
Lesson 15 - Renal Artery: Definition & Function  Take Quiz
Lesson 16 - Ureter: Definition & Function  Take Quiz
Lesson 17 - What Are Blood Clots: Symptoms & Causes  Take Quiz
Lesson 18 - Chyme: Definition & Function  Take Quiz
Lesson 19 - Afferent Arteriole: Definition & Function  Take Quiz
Lesson 20 - Efferent Arteriole: Definition & Function  Take Quiz
Lesson 21 - Do Humans Have an Open or Closed Circulatory System?  Take Quiz
Week {{::cp.getGoalWeekForTopic(22, 28)}}
Course Progress Best Score
Lesson 1 - The Environment, Levels of Ecology and Ecosystems  Take Quiz
Lesson 2 - Ecosystems, Habitats and Ecological Niches  Take Quiz
Lesson 3 - Food Chains, Trophic Levels and Energy Flow in an Ecosystem  Take Quiz
Lesson 4 - Interspecific Competition, Competitive Exclusion & Niche Differentiation  Take Quiz
Lesson 5 - Predator/Prey Interactions, Camouflage, Mimicry & Warning Coloration  Take Quiz
Lesson 6 - Symbiotic Relationships: Mutualism, Commensalism & Parasitism  Take Quiz
Lesson 7 - Populations: Density, Survivorship and Life Histories  Take Quiz
Lesson 8 - Carrying Capacity, Migration & Dispersion  Take Quiz
Lesson 9 - Dispersal, Colonization, and Island Biogeography  Take Quiz
Lesson 10 - Conservation Biology, Habitat Fragmentation, and Metapopulations  Take Quiz
Lesson 11 - Ecological Succession: From Pioneer to Climax Communities  Take Quiz
Lesson 12 - How Introduced and Invasive Species Alter Ecological Balance  Take Quiz
Lesson 13 - Biomes: Desert, Tropical Rainforest, Savanna, Coral Reefs & More  Take Quiz
Lesson 14 - Biomes: Tundra, Taiga, Temperate Grassland, and Coastlines  Take Quiz
Lesson 15 - Biogeochemical Cycling and the Phosphorus Cycle  Take Quiz
Lesson 16 - The Nitrogen Cycle, Acid Rain and Fossil Fuels  Take Quiz
Lesson 17 - Fossil Fuels, Greenhouse Gases, and Global Warming  Take Quiz
Lesson 18 - The Carbon Cycle and Long-Term Carbon Storage  Take Quiz
Lesson 19 - Human Impacts on the Environment  Take Quiz
Lesson 20 - Mullerian Mimicry: Definition & Examples  Take Quiz
Lesson 21 - Population Bottleneck: Definition & Explanation  Take Quiz
Lesson 22 - R-Selected Species: Examples & Definition  Take Quiz
Lesson 23 - What Is Greenhouse Gas? - Definition, Causes & Effects  Take Quiz
Lesson 24 - Cockroach Phylum and Class  Take Quiz
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Practice Tests in this course
Check your knowledge of this course with a 50-question practice test. Once you take the test, you will receive a detailed exam report complete with your personal statistics and even specific lessons to focus on! Take the practice test now
Your detailed study guide will include:
  • Answers and detailed explanations to each question
  • Video lessons to explain complicated concepts
Course Practice Test
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Ch. 28
AP Biology - Basic Molecular Biology Lab Techniques: Help and Review
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