Page 141 - Knowledge Organiser Yr9 24-25

Knowledge Base: Science B2: Organisation in animals Year 9
1. Levels of Organisation
1.1
What are cells?
The basic building blocks of all living organisms.
1.2
What is a tissue?
A group of cells with a similar structure and function.
1.3
What is an organ?
A group of tissues performing specific functions.
1.4
What is an organ system?
A group of organs working together to form organisms.
2.10
State two functions of bile in digestion
Emulsify fat, neutralise stomach acid before food moves into the small intestine.
2.11
State two functions of the stomach acid
Kills bacteria and creates an acidic environment
2.12
How is the small intestine adapted to absorb nutrients?
• It is very long
• Villi provide a large surface area • Villi are one cell thick
• Efficient blood supply
• Cells have many mitochondria
2.13
What are the labels in this diagram of the digestive system?
2. Digestive System
2.1
What is the function of the digestive system?
To break down food.
2.2
What happens to food molecules during digestion?
Large food molecules are broken down into small molecules and are absorbed into the bloodstream.
2.3
What is the function of the salivary glands in digestion?
Produce saliva (containing amylase enzyme).
2.4
What is the function of the stomach in digestion?
Churns food with its muscular walls, mixes food with acid.
2.5
What is the function of the liver in digestion?
To produce bile.
2.6
What is the function of the gall bladder in digestion?
Stores bile before it's released into the small intestine.
2.7
What is the function of the pancreas in digestion?
To produce and secrete enzymes.
2.8
What is the function of the small intestine in digestion?
To produce enzymes and to absorb nutrients from the digested food.
2.9
What is the function of the large intestine in digestion?
Absorb excess water.
141