Lesson Starter Name 3 enzymes produced by the

Lesson Starter • Name 3 enzymes produced by the pancreas • Draw a diagram of a fat molecule • What does Lipase do?

Learning Intention To be able to explain how food molecules move from the digestive system to the bloodstream

Think. . Someone’s farted in the class. . Who smells it first?

Think, Pair, Share Explain in terms of particles how the smell gets from one side of the class to the other

Diffusion • Where there’s A LOT to where there’s NOT. • High to low concentration • Down a concentration gradient • Passive- no energy

Diffusion and Digestion • Food broken down into SMALL and SOLUBLE forms v Starch v. Protein v. Fats • Absorbed in small intestine- DIFFUSION

Diffusion and Digestion • Small enough • Small intestine wall to bloodstream • ALOT (in intestine wall) to NOT (bloodstream)

Inside the Small Intestine • Structure of intestine helps diffusion • Finger like projections. VILLI Instructions Apparatus • 2 squares of bathmat • 2 x beakers • Measuring cylinder 1. Place both squares of mat into a beaker of water and allow to soak for 1 minute 2. Remove 1 from water and squeeze each beaker 3. Measure the contents of the beaker using a measuring cylinder 4. Repeat for second square

The effect of villi on absorption With Villi Water absorbed (mls) Without villi

Villi: discuss • What effect does the villi have on absorption? • Why is this of benefit?

Small Intestine and Diffusion • Villi- Increased surface area • Excellent blood supply • Wall= one cell thick

Copy and Complete • Diffusion is the movement of molecules from a region of _______ concentration to a region of _____ concentration. • Small food molecules pass from the wall of the _______ to the _____ by diffusion. • The small intestine has ______ to increase the ____ area. • It has an excellent _______ supply and is _____ cell thick to allow rapid diffusion.

Copy and Complete • Diffusion is the movement of molecules from a region of HIGH concentration to a region of LOW concentration. • Small food molecules pass from the wall of the SMALL INTESTINE to the BLOODSTREAM by diffusion. • The small intestine has VILLI to increase the SURFACE area. • It also has an excellent BLOOD supply and is ONE cell thick to allow rapid diffusion.

Exit pass #Small. Intestine In no more than 140 characters, describe features of the small intestine which help with diffusion.