Download Unit 6: Human Health And Physiology

Unit 6: Human Health And
Physiology
Lesson 6.1
Digestion
6.1.1 Explain why digestion of
large food molecules is essential.
• Large food
molecules are
polymers, which
must be broken
down into
monomers (via
hydrolysis) in
order to be
absorbed into
the blood.
6.1.2 Explain the need for enzymes
in digestion.
• Enzymes speed up
the rate at which
polymers are broken
down into monomers.
6.1.3 State the source, substrate, product
and optimum pH conditons for one amylase,
one protease and one lipase.
Amylase
Example of this Salivary
enzyme
amylase
Protease
Lipase
Pepsin
Pancreatic
lipase
Source
Salivary glands Wall of
stomach
Pancreas
Substrate
Starch
Proteins
Triglycerides
(fats and oils)
Product
Maltose
Small
polypeptides
Fatty acids and
glycerol
Optimum pH
7-8
1.5-3
7-8
6.1.4 Draw a diagram of the digestive
system.
• Locate: mouth,
esophagus,
stomach, small
intestine, large
intestine, anus,
liver, pancreas,
gall bladder.
6.1.5 Outline the function of the
stomach, small intestine and large
intestine.
• Stomach- primary site
for protein digestion.
• Small intestine- primary
site for overall nutrient
absorption.
• Large intestine- water
used in the digestive
process is reabsorbed
back into the body.
6.1.6 Distinguish between absorption
and assimilation.
• Absorption- the
transfer of nutrients
from the digestive
tract into the blood
stream, usually
through villi in the
small intestine.
• Assimilation- uptake
of nutrients from
blood stream into
body tissue. Occurs
after absorption.
Pictured: microvilli on a villus.
6.1.7 Explain how the structure of the
villus is related to its role in absorption of
the end products of digestion.
• Villi have a large surface area, gated ion
channels, and are dense in mitochondria,
which provide energy for the active transport
of nutrients.