Capítulo 41 Sistema Digestivo Rumiantes Termita y

Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.6
Suspension Feeders and Filter Feeders
Baleen
Capítulo 41
Sistema Digestivo
Substrate
Feeders
Fluid Feeders
Caterpillar Feces
Bulk Feeders
Dr. Fernando J. Bird-Picó
Departamento de Biología
Recinto Universitario de Mayagüez
Figura 41.18
1 Rumen
Rumiantes
2 Retículo
Termita y Trychonympha
Esófago
Intestino
4 Abomaso
Dr. Fernando J. Bird-Picó - 2016
3 Omaso
1
Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.17
Tractos
digestivos
de acuerdo
a la dieta
Digestión
Intracelular
Figure 41.7
Mouth
Tentacles
Digestión
Extracelular
Canales Alimentarios
Food
1 Digestive
enzymes released
2 Food
particles broken
down
3 Food particles
engulfed and
digested
Epidermis
Dr. Fernando J. Bird-Picó - 2016
Gastrodermis
2
Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.20
Pancreas
secretes
insulin.
Transport of
glucose into
body cells
and storage
of glucose
as glycogen
Tipos de dentición y dietas
asociadas a los mismos
Stimulus:
Blood glucose
level rises
after eating.
Homeostasis:
70–110 mg glucose/
100 mL blood
Stimulus:
Blood glucose
level drops
below set point.
Breakdown
of glycogen
and release
of glucose
into blood
Pancreas
secretes
glucagon.
Figure 41.9
Tongue
Oral cavity
Salivary
glands
Pharynx
Mouth
Esophagus
Salivary
glands
Esophagus
Liver
Sphincter
Gallbladder
Pancreas
Small
intestine
Large
intestine
Rectum
Anus
Dr. Fernando J. Bird-Picó - 2016
Sphincter
Stomach
Gallbladder
Liver
Pancreas
Stomach
Small
intestine
Large
intestine
Rectum
Anus
Schematic diagram
Duodenum of
small intestine
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Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.10-1
Figure 41.10-2
Tongue
Bolus of
food
Tongue
Bolus of
food
Pharynx
Epiglottis
up
Pharynx
Epiglottis
up
Glottis
Larynx
Trachea
To lungs
Esophageal
sphincter
contracted
Esophagus
Glottis
Larynx
Trachea
To stomach
To lungs
Figure 41.10-3
Esophageal
sphincter
contracted
Esophagus
To stomach
Figure 41.11
Esophagus
Sphincter
Pharynx
Epiglottis
up
Glottis
Larynx
Trachea
To lungs
Esophageal
sphincter
contracted
Esophagus
To stomach
Relaxed
muscles
Contracted
muscles
Sphincter
relaxed
Gastric pits on
interior surface
of stomach
Stomach
Small
intestine
Folds of
epithelial
tissue
Epithelium
3
Pepsinogen
Pepsin
2
Gastric gland
Mucous cell
Chief cell
Dr. Fernando J. Bird-Picó - 2016
Stomach
Sphincter
10 µ m
Tongue
Bolus of
food
HCl
Chief
cell
1
Cl−
H+
Secreción
de jugo
gástrico
Parietal
cell
Parietal cell
4
Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.12-1
Duodeno
Carbohydrate digestion
Oral cavity,
Polysaccharides
pharynx,
esophagus
Salivary amylase
Digestión Enzimática
Smaller
Maltose
polysaccharides
Figure 41.12-2
Carbohydrate digestion
Oral cavity,
Polysaccharides
pharynx,
esophagus
Salivary amylase
Smaller
Maltose
polysaccharides
Stomach
Figure 41.12-3
Digestión Enzimática
Carbohydrate digestion
Oral cavity,
Polysaccharides
pharynx,
esophagus
Salivary amylase
Smaller
Maltose
polysaccharides
Protein digestion
Proteins
Pepsin
Stomach
Digestión Enzimática
Protein digestion
Proteins
Pepsin
Small polypeptides
Small polypeptides
Small
intestine
(enzymes
from
pancreas)
Pancreatic amylases
Pancreatic trypsin and
chymotrypsin
Nucleic acid digestion
Fat digestion
DNA, RNA
Fat (triglycerides)
Pancreatic
nucleases
Disaccharides
Smaller
polypeptides
Nucleotides
Pancreatic lipase
Pancreatic carboxypeptidase
Small peptides
Dr. Fernando J. Bird-Picó - 2016
Glycerol, fatty acids,
monoglycerides
5
Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.12-4
Digestión Enzimática
Carbohydrate digestion
Oral cavity,
Polysaccharides Disaccharides
pharynx,
esophagus
Salivary amylase
Smaller
Maltose
polysaccharides
Protein digestion
Stomach
Proteins
Pepsin
Small polypeptides
Small
intestine
(enzymes
from
pancreas)
Pancreatic amylases
Nucleic acid digestion
Fat digestion
DNA, RNA
Fat (triglycerides)
Pancreatic trypsin and
chymotrypsin
Pancreatic
nucleases
Disaccharides
Smaller
polypeptides
Nucleotides
Digestión
de
Proteínas
Pancreatic lipase
Pancreatic carboxypeptidase
Glycerol, fatty acids,
monoglycerides
Small peptides
Small
intestine
(enzymes
from
epithelium)
Disaccharidases
Dipeptidases, carboxypeptidase, and
aminopeptidase
Nucleotidases
Nucleosides
Nucleosidases
and
phosphatases
Amino acids
Monosaccharides
Nitrogenous bases,
sugars, phosphates
Figure 41.13
Figure 41.14
Vellosidades y microvellosidades
Vein carrying
blood to liver
Villi
Microvilli (brush
border) at apical
(lumenal) surface
LUMEN
Triglycerides
OF SMALL
INTESTINE
Epithelial
cell
Fatty acids
Monoglycerides
Lumen
Epithelial
cells
Blood
capillaries
Muscle layers
Villi
Intestinal wall
Epithelial
cells
Large
circular
folds
Triglycerides
Basal
surface
Lacteal
Key
Nutrient
absorption
Lymph
vessel
Phospholipids,
cholesterol,
and proteins
Chylomicron
Lacteal
Dr. Fernando J. Bird-Picó - 2016
6
Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.19a
Figure 41.19b
• Bolo
alimenticio:
presiona pared
estomacal:
gastrina
promueve
secreción de
jugo gástico
• Acidez del quimo y
presencia de amino
ácidos y grasas:
estimula duodeno.
Secreción de
colecistocinina
(CCK) y secretina.
Apetito, hormonas y
centro de saciedad
3
• Si el quimo es rico
en grasas, la CCK y
secretina inhiben la
peristalsis y
secreción de jugo
gástico en estómago:
digestión más lenta
Secretin
and CCK
−
Gastric
juices
Key
+ Stimulation
− Inhibition
Dr. Fernando J. Bird-Picó - 2016
• Grelina: estimula apetito
• Leptina: producida en tejido
adiposo; suprime apetito
• Péptido YY: producido en
intestino delgado: suprime
apetito, motilidad gástrica y
secreción pancreática;
aumenta absorción de agua y
electrolitos en el cólon.
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Biol 3052 - Sistema Digestivo
18/04/2016
Figure 41.22
EXPERIMENT
Intestino grueso
Leptina y obesidad
Obese mouse with mutant
ob gene (left) next to wild-type
mouse
RESULTS
Genotype pairing
(red type indicates
mutant genes)
Average change
in body mass (g)
of subject
Subject
Paired with
ob+ob+ , db+db+
ob+ob+ , db+db+
8.3
ob ob, db+db+
ob ob, db+db+
38.7
ob ob, db+db+
ob+ob+, db+db+
ob ob, db+db+
ob+ob+, db db
8.2
−14.9*
*Due to pronounced weight loss and weakening, subjects in this pairing were
reweighed after less than eight weeks.
Table 41.1
Dr. Fernando J. Bird-Picó - 2016
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Biol 3052 - Sistema Digestivo
18/04/2016
Table 41.2
M
i
n
e
r
a
l
e
s
Figure 41.UN01
Veins to heart
Hepatic portal vein
Lymphatic system
Mouth
Stomach
Esophagus
Secretions
from salivary
glands
Lipids
Absorbed food
(except lipids)
Small intestine
Secretions
Secretions from liver
from gastric
Secretions from pancreas
glands
Dr. Fernando J. Bird-Picó - 2016
Liver
Absorbed
water
Anus
Large
Rectum
intestine
9