Organs and organ systems of humans and animals

In this topic

• Levels of structure: from cell to organism
• The main systems of the human body — part 1
• The main systems of the human body — part 2
• Systems work together. Animals grow more complex

Key terms

• Cell
• Tissue
• Organ
• Organ system
• Organism
• Musculoskeletal system
• Circulatory system
• Respiratory system
• Digestive system
• Excretory system
• Nervous system
• Hormone

Read the full topic

The lesson text, diagrams and 20 test questions are on the site — register free to open them.

UZRU