Table of contents

1. Overview of Cell Biology2h 49m

Evolution of the Cell
26m

Properties of the Cell
28m

History of Cell Biology
12m

Prokaryotic Cell Architecture
14m

Eukaryotic Cell Architecture
27m

Prokaryotes vs. Eukaryotes
6m

Model Organisms
18m

Viruses
20m

Overview of Tissue Structures
15m

2. Chemical Components of Cells1h 14m

Small Molecules
9m

Chemical Bonds
21m

Acids, Bases, and Buffers
9m

Four Classes of Macromolecules
23m

Properties of Macromolecules
10m

3. Energy1h 33m

Energy Sources and Generation
23m

Gibbs Free Energy and Equilibrium
19m

Activated Carriers
15m

Enzymes
18m

Enzyme Kinetics
9m

Enzyme Inhibitors
6m

4. DNA, Chromosomes, and Genomes2h 31m

DNA Discovery
9m

Structure and Function of DNA
11m

Helical Formations of DNA
8m

DNA vs. RNA
4m

Packaging of DNA
26m

The Epigenetic Code
17m

Evolution of the Genome
21m

Genomic Comparison
8m

Human Genetic Variation
18m

Transposons and Viruses
25m

5. DNA to RNA to Protein2h 31m

DNA Transcription
29m

mRNA Processing
38m

tRNA, rRNA and the Codon Code
27m

Translation
22m

mRNA Export and Nuclear Structures
20m

RNA and the Origins of Life
12m

6. Proteins1h 36m

Protein Basics
25m

Protein Folding
19m

Complex Protein Structures
7m

Enzymes and Protein Binding
14m

Protein Regulation
16m

Protein Degradation
12m

7. Gene Expression1h 42m

Basics of Gene Expression Control
14m

Epigenetic Regulation of Gene Expression
31m

Transcriptional Regulators
23m

Action of Transcriptional Regulators
11m

Post-Transcriptional Regulators
22m

8. Membrane Structure1h 4m

The Lipid Bilayer
38m

Membrane Proteins
25m

9. Transport Across Membranes1h 52m

Principles of Transmembrane Transport
16m

Passive Transport: Diffusion and Osmosis
15m

Transporters
23m

Ion Channels and Membrane Potential
18m

Ion Channels and Neurons
39m

10. Anerobic Respiration1h 5m

Breakdown and Utilization of Sugars and Fats
17m

Glycolysis
18m

Fermentation
13m

Gluconeogenesis
15m

11. Aerobic Respiration1h 11m

Overview of Cellular Respiration
12m

Mitochondria
13m

Citric Acid Cycle
12m

Electron Transport
21m

ATP Synthesis Driven from Proton Gradients
11m

12. Photosynthesis52m

Overview of Photosynthesis
6m

Chloroplast
5m

Light Dependent Reactions
24m

Light Independent Reactions
16m

13. Intracellular Protein Transport2h 18m

Membrane Enclosed Organelles
19m

Protein Sorting
9m

ER Processing and Transport
20m

Golgi Processing and Transport
17m

Vesicular Budding, Transport, and Coat Proteins
15m

Targeting Proteins to the Mitochondria and Chloroplast
7m

Lysosomal and Degradation Pathways
10m

Endocytic Pathways
21m

Exocytosis
6m

Peroxisomes
5m

Plant Vacuole
4m

14. Cell Signaling1h 28m

Overview of Cell Surface Receptors
9m

Overview of Signaling Molecules
19m

G Protein Coupled Receptors
13m

Protein Kinase Receptors
23m

Intracellular messnegers: Hormones and Nitric Oxide
5m

Phosphoinositide Signaling Pathways
6m

Integration of Multiple Signaling Pathways
6m

Signaling in Plants
3m

15. Cytoskeleton and Cell Movement1h 39m

Overview of the Cytoskeleton
10m

Intermediate Filaments
6m

Microtubules
13m

Kinesins and Dyneins
9m

Cilia and Flagella
12m

Microtubules and Cell Division
7m

Actin Filaments
19m

Actin Based Movement
7m

Muscle Contractions
13m

16. Cell Division3h 5m

Overview of the Cell Cycle
7m

Control of the Cell Cycle
21m

G1 Phase
10m

DNA Replication
1h 3m

DNA Repair and Recombination
24m

Mitosis
19m

Cytokinesis
6m

Control of Cell Size
9m

Control of Cell Death
23m

17. Meiosis and Sexual Reproduction50m

Basics of Meiotic Genetics
6m

Mendel and the Laws of Inheritance
17m

Meiosis
26m

18. Cell Junctions and Tissues48m

Cell-Cell Adhesion
9m

Cell-Cell Junctions
6m

Extracellular Matrix of Animal Cells
7m

The Basal Lamina
11m

Plant Tissue
13m

19. Stem Cells13m

Stem Cells
13m

20. Cancer44m

Overview of Cancer
10m

Oncogenes and Tumor Suppressors
9m

Carcinogens
6m

Tumor Viruses
6m

Metastasis and Cancer Spread
5m

Cancer Treatment
6m

21. The Immune System1h 6m

Overview of Host Defenses
6m

The Innate Immune Response
10m

B Cell Development
11m

Antibody Structure and Diversity
15m

T Cells
11m

MHC and Antigen Presentation
5m

Immune System Collaboration
5m

22. Techniques in Cell Biology1h 41m

The Light Microscope
5m

Electron Microscopy
6m

The Use of Radioisotopes
4m

Cell Culture
8m

Isolation and Purification of Proteins
7m

Studying Proteins
9m

Nucleic Acid Hybridization
2m

DNA Cloning
12m

Polymerase Chain Reaction - PCR
6m

DNA Sequencing
5m

DNA libraries
5m

DNA Transfer into Cells
2m

Tracking Protein Movement
2m

RNA interference
4m

Genetic Screens
13m

Bioinformatics
3m

15. Cytoskeleton and Cell Movement

Muscle Contractions

Cell Biology

15. Cytoskeleton and Cell Movement

Muscle Contractions

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Multiple Choice

Which of the following structures is composed of actin, but no myosin?

A band

M line

I band

Z line

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Verified step by step guidance

Understand the structure of a sarcomere, which is the basic unit of a muscle's striated muscle tissue. It is composed of repeating units between two Z lines.

Identify the components of a sarcomere: the A band, I band, H zone, M line, and Z line. Each of these has distinct characteristics and protein compositions.

Recall that actin and myosin are the primary proteins involved in muscle contraction. Actin is a thin filament, while myosin is a thick filament.

The I band is the region of the sarcomere that contains only thin filaments, which are primarily composed of actin. It does not contain myosin.

The A band contains both actin and myosin filaments, the M line is the center of the A band where myosin filaments are anchored, and the Z line is where actin filaments are anchored. Therefore, the I band is the structure composed of actin but no myosin.