Cells, tissues, organs and organ systems, the digestive system, and how digestive enzymes and bile break food down.
What you will learn
- Put cells, tissues, organs and organ systems in order and give examples
- Match amylase, protease and lipase to their substrates and products
- Explain the lock and key model and what bile does
From cells to organ systems
A large organism is built in levels, each made of the one before it.
- Cell: the basic unit, often specialised (a muscle cell, a red blood cell).
- Tissue: a group of cells with a similar structure and function (muscle tissue, glandular tissue, epithelial tissue).
- Organ: different tissues working together on one job. The stomach has muscle tissue to churn, glandular tissue to make juices and epithelial tissue to line it.
- Organ system: organs working together, such as the digestive system.
A leaf is an organ, not a tissue: it contains several tissues (epidermis, mesophyll, xylem and phloem).
The rest of this lesson and its 9 practice questions are locked.
In this lesson
- From cells to organ systems
- The digestive system
- Enzymes and bile
- Try it: Levels of organisation
9 practice questions, marked as you go; about 20 minutes in all.
Key terms
Liver, Gall bladder, Active site, Bile, Emulsifies, Rate
In this unit: Organisation: tissues, organs, digestion and circulation
Levels of organisation, digestion and enzymes with the amylase and food test practicals, the heart, blood and lungs, heart disease and cancer, and transport in plants.
- Organisation, digestion and enzymes
- Enzyme activity and the food tests
- The heart, blood vessels and blood
- The lungs and gas exchange
- Heart disease, risk factors and cancer
- Plant tissues and transport
- Health, lifestyle and body measurements
- Cancer: tumours, risk factors and data
All of Organisation: tissues, organs, digestion and circulation