Download Digestion Syllabus

Digestion
IB topic(s): 6.1 and D.2
Essential Idea(s): The structure of the digestive system allows it to move, digest, absorb and
egest food.
Topic
Statement(s) and Objective(s)
System
Structure
Skills/ NOS/Applications
6.1.S1: Produce an annotated
diagram of the digestive
system (Oxford Biology Course
Companion page 280).
 State the role of the digestive
system.
 Draw a diagram of the human
digestive system.
 Outline the function of the
following digestive system
structures: mouth,
esophagus, stomach, small
intestine, pancreas, liver, gall
bladder, and large intestine.
Exocrine
Glands
D.2.U2: Exocrine glands secrete to the
surface of the body or the lumen of the gut
(Oxford Biology Course Companion page 672).
 Contrast endocrine glands with exocrine
glands.
 Label a diagram of an exocrine gland with the
following terms: secretory cells, lumen, duct,
secretory vesicles, basement membrane and
acinus.
 Discuss the relationship between the
structures of an exocrine gland cell and the
function of the cell.
 State the name and location of three exocrine
glands associated with the alimentary canal.
 State the composition of saliva, gastric juice
and pancreatic juice.
Stomach
D.2.U4: Acid conditions in the stomach
favour some hydrolysis reactions and help to
control pathogens in ingested food (Oxford
Biology Course Companion page 675).
 Outline three roles of acid in the stomach.
D.2.U1: Nervous and hormonal mechanisms
control the secretion of digestive juices
(Oxford Biology Course Companion page 671).
 Describe when the secretion of digestive
juices must be controlled.
 State to mechanisms by which secretion of
gastric juices is controlled.
D.2.S1: Identify exocrine
gland cells that secrete
digestive juices from electron
micrographs (Oxford Biology
Course Companion page 67).
List three features that can be used
to identify exocrine gland cells as
viewed in electron micrographs.
D.2.NOS: Serendipity and
scientific discoveries—the role
of gastric acid in digestion was
established by William
Beaumont while observing
the process of digestion in an
open wound caused by
gunshot (Oxford Biology Course
Companion page 675).
Describe how William Beaumont
was able to determine the role of
the stomach in chemical digestion
of food.
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D.2.U3: The volume and content of gastric
secretions are controlled by nervous and
hormonal mechanisms (Oxford Biology
Course Companion page 671).
Use a flow chart or concept map, to show the
interactions between nervous and hormonal
mechanisms that regulated the secretion of gastric
juices.
Ulcers
D.2.A3: Helicobacter pylori infection as a
cause of stomach ulcers (Oxford Biology
Course Companion page 675).
 Define stomach ulcer.
 Outline evidence that suggest Helicobacter
pylori infection has a role in stomach
ulcers and stomach cancer.
D.2.A1: The reduction of stomach acid
secretion by proton pump inhibitor drugs
(Oxford Biology Course Companion page 676).
 State the role of stomach mucus.
 State the cause of ulcer and acid reflux.
 Outline the role of the H+, K+ -ATPase
protein pump in the production of an acidic
stomach.
 Outline the use, function and effect of
proton pump inhibitors to treat gastric
disease.
Pancreatic
Enzymes
6.1.U2: The pancreas secretes enzymes into Utilization: some hydrolytic
the lumen of the small intestine (amylase,
enzymes have economic
lipase, endopeptidase) (Oxford Biology
importance, for example
Course Companion page 282).
amylase in production of
 List the name and substrate of the three
sugars from starch and in the
major classes of enzymes secreted by the
brewing of beer
pancreas.
6.1.U3: Enzymes digest most
macromolecules in food into monomers in
the small intestine (Oxford Biology Course
Companion page 282).
 List the name, substrate and product of four
pancreatic enzymes that hydrolyze food in
the small intestine.
 List the name, substrate and product of four
enzymes produced by gland cells in the small
intestine wall.
 Describe why enzymes produced by gland
cells in the small intestine wall often remain
immobilized in the cell membrane.
Small
intestine
6.1.U1: The contraction of circular and
longitudinal muscle of the small intestine
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mixes the food with enzymes and moves it
along the gut (Oxford Biology Course
Companion page 281).
 Outline the role of peristalsis in the
digestive process.
6.1.S2: Identification of tissue layers in
transverse sections of the small intestine
viewed with a microscope or in a
micrograph (Oxford Biology Course
Companion page 281).
 Outline the function of the layers of tissue
found in the wall of the small intestine.
 Label the layers of tissue found in the wall of
the small intestine as viewed with a
microscope or in a micrograph.
Absorptio
n
6.1.U5: Villi absorb monomers formed by
digestion as well as mineral ions and
vitamins (Oxford Biology Course Companion
page 283).
 Define absorption.
 List materials absorbed by the villi cells of the
small intestine.
6.1.U4: Villi increase the surface area of
epithelium over which absorption is carried
out (Oxford Biology Course Companion page
67).
 List three adaptations that increase the
surface area for absorption on the small
intestine.
 Draw the villi as viewed in cross section.
 Label the following on a diagram of a
villi: capillary, epithelial cell, lacteal, and
goblet cell.
 State the function of the following villi
structures: capillary, epithelial cell, lacteal,
and goblet cell.
D.2.U5: The structure of cells of the
epithelium of the villi is adapted to the
absorption of food (Oxford Biology Course
Companion page 673).
 Outline the role of the following
D.2.S1: Identification of
exocrine gland cells that
secrete digestive juices and
villus epithelium cells that
absorb digested foods from
electron micrographs (Oxford
Biology Course Companion page
674).
 List four features that can be
used to identify villus
epithelium cells as viewed in
electron micrographs.
6.1.NOS: Use models as
representations of the real
world-dialysis tubing can be
used to model absorption in
the intestine (Oxford Biology
Course Companion page 286).
 Explain the use of models in
physiology research.
 State two examples of model
systems used to study
digestion.
 State limitations of using
model systems in physiology
research.
structures of villi epithelial cells: tight
junctions, microvilli, mitochondria,
pinocytic vesicles, proteins imbedded on
the apical surface and proteins imbedded
on the basal surface.
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6.1.U6: Different methods of membrane
transport are required to absorb different
nutrients (Oxford Biology Course Companion
page 284).
 List four methods of membrane transport
required to absorb nutrients.
 Describe the absorption of triglycerides.
 Describe the absorption of glucose.
6.1.A1: Processes occurring in the small
intestine that results in the digestion of
starch and transport of the products of
digestion to the liver (Oxford Biology Course
Companion page 285).
 Describe the structure of starch.
 Outline the source, function and specificity of
amylase.
 Outline the digestion of maltose, maltotriose
and dextrins into glucose.
 Describe absorption of glucose by villus
epithelial cells.
 Describe transport of glucose into and
through villi capillaries.
6.1.A2: Use of dialysis tubing to model
absorption of digested food in the intestine
(Oxford Biology Course Companion page 287).
Explain the use of dialysis tubing as a model for
the small intestine.
Egestion
D.2.U7: Materials not absorbed are egested
(Oxford Biology Course Companion page 676).
 Define dietary fibre.
 State two examples of dietary fibre.
 Define egestion.
 List materials that are egested from the body.
D.2.U6: The rate of transit of materials
through the large intestine is positively
correlated with their fibre content (Oxford
Biology Course Companion page 676).
 List benefits of fibre in a healthy diet.
 State the relationship between food fibre
contents and rate of transit through the large
intestine.
D.2.A2: Dehydration due to cholera toxin
(Oxford Biology Course Companion page 677).
 Outline the cause and consequences of
cholera infection.
 Explain the effect of cholera toxin on
intestinal cells.
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