Animal tissues, organs and organ systems Flashcards
What does the digestive system do?
Breaks down large insoluble molecules, that your body cannot absorb, into smaller, soluble molecules that can be absorbed and used in your cells
Order of the digestive system?
mouth esophagus stomach liver/gall bladder pancreas small intestine large intestine rectum anus
What happens in the mouth?
chewing (physical digestion)
saliva contains amylase which breaks down starch
What happens in the stomach?
Churning (physical digestion)
Main place where enzymes break down the large insoluble food molecules into smaller particles
What is the pH in the stomach?
Low pH, very acidic
contains hydrochloric acid to kill the bateria
What happens in the liver/gall bladder?
Liver produces bile, which helps the digestion of lipids
The gall bladder stores the bile
What happens in the pancreas?
It is a gland that relases enzymes (protease, carbohydrase, lipase)
What happens in the small intestine?
Where the soluble food molecules are absorbed into the blood
What happens in the large intestine?
Absorbs water from undigested food
What happens in the rectum and anus?
Egestion
How is the digestive system adapted? (2)
- Temperature is kept at 37 to allow enzymes to work as fast as possible
- Body makes a variety of different chemicals that help keep conditions ideal for enzymes as different enzymes work in different pH levels
How is the stomach adapted? (3)
- Secrets pepsin
- Has hydrochloric acid to kill most of the bacteria in food
- Produces mucus that coats the stomach walls to protect it from the acid
How is the small intestine adapted? (3)
- One cell thick so that substances can pass through quickly
- Many tiny villi to create a large surface area
- Good blood supply to maintain concentration gradient
What are the two types of carbohydrates?
- Simple sugars that only contain 1/2 sugar units
2. Complex sugars that are long chains of simple sugars bonded together
What color are carbohydrates in Benedict solution?
blue
What color are carbohydrates in iodine solution?
blue/black
What are carbohydrates broken down into?
simple sugars
What are carbohydrate rich foods?
bread
potatoes
rice
pasta