Table of contents

Skip topic navigation

1. Introduction to Biology2h 42m

Introduction to Biology
9m

Characteristics of Life
12m

Life's Organizational Hierarchy
27m

Natural Selection and Evolution
26m

Introduction to Taxonomy
26m

Scientific Method
27m

Experimental Design
30m

2. Chemistry3h 40m

Atoms- Smallest Unit of Matter
57m

Isotopes
39m

Introduction to Chemical Bonding
21m

Covalent Bonds
40m

Noncovalent Bonds
5m

Ionic Bonding
37m

Hydrogen Bonding
19m

3. Water1h 26m

Introduction to Water
7m

Properties of Water- Cohesion and Adhesion
7m

Properties of Water- Density
8m

Properties of Water- Thermal
14m

Properties of Water- The Universal Solvent
17m

Acids and Bases
12m

pH Scale
18m

4. Biomolecules2h 23m

Carbon
8m

Functional Groups
9m

Introduction to Biomolecules
2m

Monomers & Polymers
11m

Carbohydrates
23m

Proteins
25m

Nucleic Acids
34m

Lipids
28m

5. Cell Components2h 26m

Microscopes
10m

Prokaryotic & Eukaryotic Cells
26m

Introduction to Eukaryotic Organelles
16m

Endomembrane System: Protein Secretion
29m

Endomembrane System: Digestive Organelles
12m

Mitochondria & Chloroplasts
21m

Endosymbiotic Theory
10m

Introduction to the Cytoskeleton
10m

Cell Junctions
8m

6. The Membrane2h 31m

Biological Membranes
10m

Types of Membrane Proteins
7m

Concentration Gradients and Diffusion
9m

Introduction to Membrane Transport
14m

Passive vs. Active Transport
13m

Osmosis
33m

Simple and Facilitated Diffusion
17m

Active Transport
30m

Endocytosis and Exocytosis
15m

7. Energy and Metabolism2h 0m

Introduction to Energy
15m

Laws of Thermodynamics
15m

Chemical Reactions
9m

ATP
20m

Enzymes
14m

Enzyme Activation Energy
9m

Enzyme Binding Factors
9m

Enzyme Inhibition
10m

Introduction to Metabolism
8m

Negative & Positive Feedback
7m

8. Respiration2h 40m

Redox Reactions
15m

Introduction to Cellular Respiration
22m

Types of Phosphorylation
12m

Glycolysis
19m

Pyruvate Oxidation
8m

Krebs Cycle
16m

Electron Transport Chain
14m

Chemiosmosis
7m

Review of Aerobic Cellular Respiration
19m

Fermentation & Anaerobic Respiration
23m

9. Photosynthesis2h 49m

Introduction to Photosynthesis
17m

Leaf & Chloroplast Anatomy
10m

Electromagnetic Spectrum
6m

Pigments of Photosynthesis
16m

Stages of Photosynthesis
6m

Light Reactions of Photosynthesis
34m

Calvin Cycle
21m

Photorespiration
17m

C3, C4 & CAM Plants
20m

Review of Photosynthesis
18m

10. Cell Signaling59m

Introduction to Cell Signaling
16m

Classes of Signaling Receptors
13m

Types of Cell Signaling
15m

Signal Amplification
13m

11. Cell Division2h 47m

Introduction to Cell Division
22m

Organization of DNA in the Cell
17m

Introduction to the Cell Cycle
7m

Interphase
18m

Phases of Mitosis
48m

Cytokinesis
16m

Cell Cycle Regulation
15m

Review of the Cell Cycle
7m

Cancer
13m

12. Meiosis2h 0m

Genes & Alleles
15m

Homologous Chromosomes
12m

Life Cycle of Sexual Reproducers
5m

Introduction to Meiosis
15m

Meiosis I
12m

Meiosis II
11m

Genetic Variation During Meiosis
37m

Mitosis & Meiosis Review
9m

13. Mendelian Genetics4h 44m

Introduction to Mendel's Experiments
7m

Genotype vs. Phenotype
17m

Punnett Squares
13m

Mendel's Experiments
26m

Mendel's Laws
18m

Monohybrid Crosses
19m

Test Crosses
14m

Dihybrid Crosses
20m

Punnett Square Probability
26m

Incomplete Dominance vs. Codominance
20m

Epistasis
7m

Non-Mendelian Genetics
12m

Pedigrees
6m

Autosomal Inheritance
21m

Sex-Linked Inheritance
43m

X-Inactivation
9m

14. DNA Synthesis2h 27m

The Griffith Experiment
12m

The Hershey-Chase Experiment
13m

Chargaff's Rules
9m

Discovering the Structure of DNA
18m

Meselson-Stahl Experiment
12m

Introduction to DNA Replication
22m

DNA Polymerases
9m

Leading & Lagging DNA Strands
14m

Steps of DNA Replication
15m

DNA Repair
7m

Telomeres
11m

15. Gene Expression3h 20m

Central Dogma
7m

Introduction to Transcription
20m

Steps of Transcription
22m

Eukaryotic RNA Processing and Splicing
20m

Introduction to Types of RNA
9m

Genetic Code
23m

Introduction to Translation
30m

Steps of Translation
23m

Post-Translational Modification
6m

Review of Transcription vs. Translation
12m

Mutations
21m

16. Regulation of Expression3h 31m

Introduction to Regulation of Gene Expression
13m

Prokaryotic Gene Regulation via Operons
27m

The Lac Operon
21m

Glucose's Impact on Lac Operon
25m

The Trp Operon
20m

Review of the Lac Operon & Trp Operon
11m

Introduction to Eukaryotic Gene Regulation
9m

Eukaryotic Chromatin Modifications
16m

Eukaryotic Transcriptional Control
22m

Eukaryotic Post-Transcriptional Regulation
28m

Eukaryotic Post-Translational Regulation
13m

17. Viruses37m

Viruses
37m

18. Biotechnology2h 58m

Introduction to DNA-Based Technology
5m

Introduction to DNA Cloning
10m

Steps to DNA Cloning
35m

Introduction to Polymerase Chain Reaction
13m

The Steps of PCR
23m

Gel Electrophoresis
17m

Southern Blotting
21m

DNA Fingerprinting
13m

Introduction to DNA Sequencing
7m

Dideoxy Sequencing
30m

19. Genomics17m

Genomes
17m

20. Development1h 5m

Developmental Biology
31m

Animal Development
20m

Plant Development
13m

21. Evolution3h 1m

Introduction to Evolution and Natural Selection
50m

History of Evolutionary Thought
29m

Natural Selection
26m

Evidence of Natural Selection
22m

Evidence of Evolution
36m

Misconceptions About Evolution
15m

22. Evolution of Populations3h 53m

Evolution of Populations
11m

Genetic Variation
24m

Genetics and Allele Frequencies
23m

The Hardy-Weinberg Principle
1h 4m

Assumptions of the Hardy-Weinberg Principle
12m

Non-Random Mating
10m

Natural Selection
39m

Genetic Drift
19m

Gene Flow
10m

Putting it All Together
16m

23. Speciation1h 37m

Introduction to Speciation
3m

The Biological Species Concept
32m

Other Species Concepts
15m

Allopatric and Sympatric Speciation
32m

Hybrid Zones
9m

Speciation Time Scales
4m

24. History of Life on Earth2h 6m

Origin of Life
13m

The Fossil Record
24m

History of Life on Earth
14m

Extinctions
30m

Adaptive Radiation
34m

Evolution of Complexity
9m

25. Phylogeny2h 31m

Introduction to Phylogeny
15m

Phylogeny
54m

Building Phylogenetic Trees
49m

Cladistics
16m

Phylogenetics and Genome Evolution
16m

26. Prokaryotes4h 59m

Introduction to Prokaryotes
31m

Prokaryotic Cell Structure
48m

Prokaryotic Motility
12m

Prokaryotic Reproduction
1h 21m

Prokaryotic Metabolism
52m

Prokaryotic Diversity
36m

Prokaryotes in the Environment
36m

27. Protists1h 12m

Introduction to Protists
13m

Evolution of Protists
9m

Protist Life Cycles
37m

Eukaryotic Supergroups: Exploring Protist Diversity
12m

28. Plants1h 22m

Land Plants
35m

Nonvascular Plants
13m

Seedless Vascular Plants
6m

Seed Plants
26m

29. Fungi36m

Fungi
19m

Fungi Reproduction
17m

30. Overview of Animals34m

Overview of Animals
34m

31. Invertebrates1h 2m

Porifera and Cnideria
10m

Lophotrochozoans
24m

Ecdysozoans
24m

Echinoderms
3m

32. Vertebrates50m

Chordates
28m

Aminotes
9m

Primates and Homonids
12m

33. Plant Anatomy1h 3m

Roots and Shoots
26m

Tissues
16m

Growth
20m

34. Vascular Plant Transport1h 2m

Water Potential
1h 2m

35. Soil37m

Soil and Nutrients
20m

Nitrogen Fixation
16m

36. Plant Reproduction47m

Flowers
33m

Seeds
14m

37. Plant Sensation and Response1h 9m

Phototropism
36m

Tropisms and Hormones
19m

Plant Defenses
14m

38. Animal Form and Function1h 19m

Animal Tissues
27m

Metabolism and Homeostasis
35m

Thermoregulation
16m

39. Digestive System1h 10m

Digestion
1h 3m

Blood Sugar Homeostasis
7m

40. Circulatory System1h 49m

Circulatory and Respiratory Anatomy
40m

Heart Physiology
34m

Gas Exchange
33m

41. Immune System1h 12m

Immune System
9m

Innate Immunity
15m

Adaptive Immunity
47m

42. Osmoregulation and Excretion50m

Osmoregulation and Excretion
50m

43. Endocrine System1h 4m

Endocrine System
1h 4m

44. Animal Reproduction1h 2m

Animal Reproduction
1h 2m

45. Nervous System1h 55m

Neurons and Action Potentials
1h 8m

Central and Peripheral Nervous System
46m

46. Sensory Systems46m

Sensory System
46m

47. Muscle Systems23m

Musculoskeletal System
23m

48. Ecology3h 11m

Introduction to Ecology
20m

Biogeography
14m

Earth's Climate Patterns
50m

Introduction to Terrestrial Biomes
10m

Terrestrial Biomes: Near Equator
13m

Terrestrial Biomes: Temperate Regions
10m

Terrestrial Biomes: Northern Regions
15m

Introduction to Aquatic Biomes
27m

Freshwater Aquatic Biomes
14m

Marine Aquatic Biomes
13m

49. Animal Behavior28m

Animal Behavior
28m

50. Population Ecology3h 41m

Introduction to Population Ecology
28m

Population Sampling Methods
23m

Life History
12m

Population Demography
17m

Factors Limiting Population Growth
14m

Introduction to Population Growth Models
22m

Linear Population Growth
6m

Exponential Population Growth
29m

Logistic Population Growth
32m

r/K Selection
10m

The Human Population
22m

51. Community Ecology2h 46m

Introduction to Community Ecology
2m

Introduction to Community Interactions
9m

Community Interactions: Competition (-/-)
38m

Community Interactions: Exploitation (+/-)
23m

Community Interactions: Mutualism (+/+) & Commensalism (+/0)
9m

Community Structure
35m

Community Dynamics
26m

Geographic Impact on Communities
21m

52. Ecosystems2h 36m

Introduction to Ecosystems
24m

Energy Flow Through Ecosystems
39m

Making Sense of Ecosystem Production & Efficiency
19m

Energy & Biomass Pyramids
16m

Factors Impacting Primary Production
12m

Biogeochemical Cycles
44m

53. Conservation Biology24m

Conservation Biology
24m

36. Plant Reproduction

Flowers

General Biology

36. Plant Reproduction

Flowers

Previous problemNext problem

Struggling with General Biology?

Join thousands of students who trust us to help them ace their exams!Watch the first video

Multiple Choice

In botanical terms, what part of the plant is a pumpkin?

A fruit (a mature ovary containing seeds)

A root used for nutrient absorption and storage

A stem modified for photosynthesis

A flower (the reproductive structure before fertilization)

Previous problemNext problem

5:18m

Watch next

Master Alteration of Generations with a bite sized video explanation from Jason

Start learning

Flowers practice set

Problem sets built by lead tutors

Expert video explanations

Go to Practice

Download the Mobile app

Accessibility

Privacy

Do not sell my personal information