Biology archive
Biology is the study of life.
25 units306 videos47 hours
Learn it live with a class on Puzzicle · Teachers: use it with your class
Unit 1: Intro to biology
Welcome to biology!
The science of biology
Water and life
Unit 2: Water, acids, and bases
Hydrogen bonding in water
Cohesion and adhesion
Temperature and state changes in water
Unit 3: Macromolecules
Carbohydrates
Lipids
Nucleic acids
Unit 4: Energy and enzymes
Energy in metabolism
Laws of thermodynamics
Free energy
ATP and reaction coupling
Introduction to enzymes
Unit 5: Structure of a cell
Introduction to cells
Prokaryotic and eukaryotic cells
Tour of a eukaryotic cell
Extracellular structures and cell-cell junctions
Unit 6: Membranes and transport
The plasma membrane
Cell membranes
Diffusion and osmosis
Passive transport
Active transport
Unit 7: Cellular respiration
Introduction to cellular respiration
Steps of cellular respiration
Pyruvate oxidation and the citric acid cycle
Oxidative phosphorylation
Variations on cellular respiration
Unit 8: Photosynthesis
Intro to photosynthesis
The light-dependent reactions
The Calvin cycle
Photorespiration: C3, C4, and CAM plants
Unit 9: Cell signaling
How cells signal to each other
Communication in single-celled organisms
Communication in multicellular organisms
Unit 10: Cell division
Introduction to cell division
Development & differentiation
The cell cycle and mitosis
Meiosis
Cell cycle regulation, cancer, and stem cells
Unit 11: Classical and molecular genetics
Mendelian genetics
Variations on Mendelian genetics
Chromosomal basis of genetics
Sex linkage, chromosomal mutations, & non-nuclear inheritance
Molecular basis of genetics
Environmental effects on phenotype
Unit 12: DNA as the genetic material
Structure of DNA
Discovery of DNA
Unit 13: Central dogma (DNA to RNA to protein)
Central dogma and the genetic code
Transcription
Unit 14: Gene regulation
Unit 15: Biotechnology
Intro to biotechnology
Unit 16: Bacteria and archaea
Prokaryote structure
Unit 17: Viruses
Viruses
Unit 18: Evolution and the tree of life
Evidence of evolution
Evolution and natural selection
Population genetics
Population diversity and resilience ✓ Check-ins4:29
Allele frequency ✓ Check-ins7:27
Hardy-Weinberg equation ✓ Check-ins8:14
Applying the Hardy-Weinberg equation ✓ Check-ins5:30
Discussions of conditions for Hardy-Weinberg ✓ Check-ins6:54
Genetic drift, bottleneck effect, and founder effect ✓ Check-ins10:47
Speciation and evolutionary trees
Taxonomy and the tree of life ✓ Check-ins12:41
Species ✓ Check-ins8:49
Speciation ✓ Check-ins10:47
Reproductive isolation ✓ Check-ins4:59
Biodiversity and natural selection ✓ Check-ins9:03
Genetic variation, gene flow, and new species ✓ Check-ins11:52
Discovering the tree of life ✓ Check-ins7:50
Understanding and building phylogenetic trees ✓ Check-ins10:57
Artificial selection
Unit 19: History of life on Earth
Formation of Earth and early life
The diversification of life
Unit 20: Ecology
Intro to ecology
Intro to population ecology
Population growth & regulation
Exponential and logistic growth in populations ✓ Check-ins7:32
Logistic growth versus exponential growth ✓ Check-ins10:02
Population growth rate based on birth and death rates ✓ Check-ins3:14
Per capita population growth and exponential growth ✓ Check-ins ✎ Fixed a slip8:45
Population regulation ✓ Check-ins10:33
Predator-prey cycles ✓ Check-ins5:09
Thomas Malthus and population growth ✓ Check-ins8:13
Intro to community ecology
Community structure & diversity
Intro to ecosystems
Biogeochemical cycles
Unit 21: Biodiversity and conservation
Ecosystems & ecosystem services
Global distribution of biodiversity
Biogeography: Where life lives ✓ Check-ins1:50
What is a biodiversity hotspot? ✓ Check-ins5:54
How biodiversity is distributed globally ✓ Check-ins7:18
Why biodiversity is distributed unevenly ✓ Check-ins10:49
New localities lead to new biodiversity ✓ Check-ins10:30
Tropical rainforest diversity ✓ Check-ins4:04
Simpson's index of diversity ✓ Check-ins5:43
Threats to biodiversity
Human activities that threaten biodiversity ✓ Check-ins12:51
How did all dinosaurs except birds go extinct? ✓ Check-ins1:55
Were dinosaurs undergoing long-term decline before mass extinction? ✓ Check-ins2:44
Introduced species and biodiversity ✓ Check-ins9:56
How does climate change affect biodiversity? ✓ Check-ins12:07
Demystifying ocean acidification and biodiversity impacts ✓ Check-ins12:13
Biodiversity and extinction, then and now ✓ Check-ins12:22
Protecting biodiversity
Unit 22: Behavioral biology
Unit 23: Human biology
Circulatory and pulmonary systems
The neuron and nervous system
The kidney and nephron
Muscles
Immunology
Role of phagocytes in innate or nonspecific immunity ✓ Check-ins16:20
Types of immune responses: Innate and adaptive, humoral vs. cell-mediated ✓ Check-ins8:07
B lymphocytes (B cells) ✓ Check-ins14:13
Professional antigen presenting cells (APC) and MHC II complexes ✓ Check-ins11:33
Helper T cells ✓ Check-ins20:33
Cytotoxic T cells and MHC I complexes ✓ Check-ins9:16
Review of B cells, CD4+ T cells and CD8+ T cells ✓ Check-ins11:07
Inflammatory response ✓ Check-ins14:35
Unit 24: Plant biology
Plant responses to light
Unit 25: AP free response worked examples
2015 Free response worked examples
1a-c, Responses to the environment ✓ Check-ins11:12
1d-e, Responses to the environment & natural selection7:04
2a-b, Cellular respiration & common ancestry ✓ Check-ins11:44
2c-d, Cellular respiration & cell compartmentalization and its origins ✓ Check-ins9:32
3a-b, Phylogeny ✓ Check-ins8:31
4a-b, Meiosis and genetic diversity ✓ Check-ins5:24
5a-b, Responses to the environment ✓ Check-ins6:54
6a-c, Population ecology ✓ Check-ins5:56
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