1) The document discusses energy use and metabolism in animals. It shows graphs comparing the basal metabolic rate (BMR) of different animals in relation to their body size and mass. Smaller animals tend to have higher BMRs per kg of body mass. 2) The document then discusses digestion in animals. It describes the different digestive compartments and pathways for ingestion, digestion, absorption and elimination in various animal groups. Enzymatic breakdown of nutrients occurs inside or outside cells. 3) The stages of digestion - ingestion, digestion, absorption and elimination - are examined for different digestive system structures in animals like earthworms, birds and humans. Absorption of breakdown products like glucose, amino acids

1. Fig. 40-17
Organic molecules
in foodExternal
environment
Animal
body Digestion and
absorption
Nutrient molecules
in body cells
Carbon
skeletons
Cellular
respiration
ATP
Heat
Energy lost
in feces
Energy lost in
nitrogenous
waste
Heat
Biosynthesis
Heat
Heat
Cellular
work

2. Stofwisselingssnelheid: de hoeveelheid energie dat een dier
gebruikt in een bepaalde tijd. Dit is bijvoorbeeld te meten door
de hoeveelheid verbruikte zuurstof of geproduceerde
koolstofdioxide te meten.
Quantifying Energy Use
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

3. Shrew
Harvest mouse
Mouse
Ground squirrel
Rat
Cat Dog
Sheep
Human
Horse
Elephant
Body mass (kg) (log scale)
BMR(LO2/hr)(logscale)
(a) Relationship of BMR to body size
10–3 10–2
10–2
10–1
10–1
1
1
10 102
103
10
102
103

4. 103
10210110–110–210–3
0
1
2
3
4
5
6
7
8
Body mass (kg) (log scale)
(b) Relationship of BMR per kilogram of body mass to body size
BMR(LO2/hr)(perkg)
Shrew
Harvest mouse
Mouse
Rat
Ground squirrel
Cat
Sheep
Dog
Human
Horse
Elephant

5. Overview: The Need to Feed
- Herbivoren
- Carnivoren
- Omnivoren

6. An animal’s diet must supply chemical energy, organic
molecules, and essential nutrients
Dieren hebben nodig:
- Chemische energie  ATP
- Organisch C & N  organische moleculen
- Essentiele voedingsstoffen

7. Essential Nutrients
Vier groepen essentiele voedingsstoffen:
- Essentiele aminozuren
- Essentiele vetzuren
- Vitaminen
- Mineralen

8. Assessing Nutritional Needs
Inzicht in wat mensen nodig hebben komt van epidemiologie,
de studie van gezondheid en ziekten in populaties.
Afwijkingen van het ruggenmerg (open rug, spina bifida)
kunnen veroorzaakt worden door een te kort aan foliumzuur.

9. Ingestion Digestion Absorption Elimination
Undigested
material
Chemical digestion
(enzymatic hydrolysis)
Nutrient
molecules
enter body
cells
Small
molecules
Mechanical
digestion
Food
Pieces
of food
1 2 3 4
Opname Vertering Absorptie Verwijdering
Voedselverwerking

10. Voedselopname: suspensie eters

11. Voedselopname: substraat eters

12. Voedselopname: vloeistof eters

13. Voedselopname: bulk eters

14. Digestive Compartments
Dieren verteren hun voedsel in speciale compartimenten,
op deze manier reduceren ze het risico op schade aan
eigen weefsels.

15. Intracellular Digestion
Intracellulaire vertering: voedseldeeltjes worden opgenomen
door endocytose (fagocytose & pinocytose) en binnen
vacuoles verteerd.
Extracellulaire vertering: afbraak van voedseldeeltjes buiten
de cellen.
Intra = binnen
Extra = buiten

16. Gastrovasculaire holte & Spijsverteringskanaal

17. Esophagus
Mouth
Pharynx
Crop Gizzard
Typhlosole
Intestine
Lumen of intestine
Anus
(b) Grasshopper
Foregut
(c) Bird
(a) Earthworm
Midgut Hindgut
Esophagus Rectum
Anus
Mouth
Crop
Gastric cecae
Esophagus
Mouth
Crop
Anus
Stomach
Gizzard
Intestine

18. Bloodstream
Veins to heart
Lymphatic
system
Small intestine
Esophagus
Stomach
Lipids
Mouth
Hepatic portal vein
Absorbed food
(except lipids)
Absorbed
water
Secretions from
the gastric glands
of the stomach
Secretions from the
pancreas and the liver
Liver
Rectum
Anus
Large
intestine

19. Cecum
Anus Anus
Ascending
portion of
large intestine
Gall-
bladder
Small
intestine
Large
intestine
Small
intestine
Rectum
Pancreas
Liver
Salivary glands
Tongue
Oral cavity
Pharynx
Esophagus
Sphincter
Stomach
Sphincter
Duodenum of
small intestine
Appendix
Liver
Pancreas
Small
intestine
Large
intestine
Rectum
Stomach
Gall-
bladder
A schematic diagram of the
human digestive system
Esophagus
Salivary
glands
Mouth

20. Oral cavity,
pharynx,
esophagus
Stomach
Lumen of
small intes-
tine
Epithelium
of small
intestine
(brush
border)
Carbohydrate digestion
Polysaccharides
Smaller polysaccharides,
maltose
Polysaccharides
Maltose and other
disaccharides
Disaccharides
Protein digestion Nucleic acid digestion Fat digestion
Proteins
Small polypeptides
Pepsin
Pancreatic amylases
Salivary amylase
Disaccharidases
Monosaccharides
Small peptides
Amino acids
Amino acids
Polypeptides
Smaller
polypeptides
Pancreatic trypsin and
chymotrypsin
Pancreatic carboxypeptidase
Dipeptidases, carboxypeptidase,
and aminopeptidase
DNA, RNA
Pancreatic
nucleases
Fat globules
Nucleotides
Fat droplets
Nucleosides
Nitrogenous bases,
sugars, phosphates
Nucleotidases
Nucleosidases
and
phosphatases
Glycerol, fatty
acids, monoglycerides
Bile salts
Pancreatic lipase
(starch, glycogen) (sucrose, lactose)

21. Larynx
Trachea
Epiglottis
up
Pharynx
Tongue
Glottis
Esophagus
Esophageal
sphincter
contracted
Food
To
stomach
To
lungs
Epiglottis
down
Esophageal
sphincter
relaxed
Glottis up
and closed
Epiglottis
up
Esophageal
sphincter
contracted
Sphincter
relaxed
Relaxed
muscles
Contracted
muscles
Relaxed
muscles
Stomach
Glottis
down
and open
Epiglottis = strotklepje
Pharynx = keelholte
Glottis = stemspleet
Larynx = strottenhoofd
Trachea = luchtpijp
Sphincter = sluitspier
Oesophagus = slokdarm

22. Interior surface
of stomach
Esophagus
Chief cells
Small
intestine
Epithelium
Stomach
Sphincter
Parietal cell
Pepsinogen and HCl
are secreted.
HCl converts
pepsinogen to pepsin.
Pepsin activates
more pepsinogen.
Chief cell
Folds of
epithelial
tissue
Pepsin
Sphincter
Pepsinogen
HCl
H+
Cl–
Parietal cells
Mucus cells
Gastric gland
1
2
2
3
3
1
5µm

23. Secretin
and CCK
Stomach
Gallbladder
Liver
+
Duodenum of
small intestine
Bile
Gastrin
Secretin
Pancreas
CCK
CCK
Key
Stimulation
Inhibition
+
–
+
+
+ –

24. Muscle layers
Microvilli (brush
border) at apical
(lumenal) surface
Vein carrying blood
to hepatic portal vein
Villi
Intestinal wall
Key
Nutrient
absorption
Large
circular
folds
Blood
capillaries
Epithelial
cells
Villi
Lymph
vessel
Basal
surface
Lacteal
Epithelial cells
Lumen

25. Lumen
of small
intestine
Lacteal
Chylomicron
Phospholipids,
cholesterol,
and proteins
Triglycerides
Monoglycerides
Triglycerides
Fatty acids
Epithelial
cell
Vet is onoplosbaar in
water.
Lipase breekt vet
(trigliceriden) af tot
vetzuren en
monoglyceriden, deze
zijn in staat de
celmembraan te
passeren.
Nadat er weer
triglyceriden zijn gevormd,
worden deze in water
oplosbare druppels
opgenomen.
Chylomicronen passeren
de celmembraan en
worden opgenomen in het
lymfevatenstelsel.
De opname van vet

26. Homeostasis:
90 mg glucose/
100 mL blood
Stimulus:
Blood glucose
level rises
after eating.
Stimulus:
Blood glucose
level drops
below set point.
InsulineOpname glucose
lichaamscellen
Opslag glucose
als glycogeen
Glucagon
Afbraak glycogeen
tot glucose

27. Leptin
PYY
Insulin
Ghrelin
Trek regulerende hormonen
Ghreline, afgescheiden door de
maagwand, is eetlust opwekkend.
Insuline, afgescheiden door de
alvleesklier, onderdrukt de eetlust.
Leptine, afgescheiden door de
vetweefsel, onderdrukt de eetlust.
PYY, afgescheiden door de
dunnedarm, onderdrukt de eetlust.

28. Fig. 41-18
Incisors
(c) Omnivore
Molars
(b) Herbivore
(a) Carnivore
Canines
Premolars

29. Fig. 41-19
Cecum
Small intestine
HerbivoreCarnivore
Colon
(large
intestine)
Stomach
Small
intestine

30. Esophagus
Omasum
(boekmaag)
Abomasum (lebmaag)
Intestine
Rumen (pens) Reticulum (netmaag)1 2
4 3