Transcript of © 2015 Pearson Education, Inc. Figure 14.11 Schematic summary of gastrointestinal tract activities....
- Slide 1
- 2015 Pearson Education, Inc. Figure 14.11 Schematic summary of
gastrointestinal tract activities. Digestion Defecation Mechanical
breakdown Ingestion Propulsion Absorption Food Pharynx Esophagus
Chewing (mouth) Churning (stomach) Segmentation (small intestine)
Swallowing (oropharynx) Peristalsis (esophagus, stomach, small
intestine, large intestine) Stomach Lymph vessel Blood vessel
Mainly H 2 O Feces Anus Small intestine Large intestine
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- 2015 Pearson Education, Inc.
- Slide 3
- Figure 14.1 The human digestive system: Alimentary canal and
accessory organs. Mouth (oral cavity) Tongue Esophagus Parotid
gland Sublingual gland Submandibular gland Salivary glands Pharynx
Stomach Pancreas (Spleen) Transverse colon Descending colon
Ascending colon Cecum Sigmoid colon Rectum Appendix Anal canal Anus
Small intestine Duodenum Jejunum Ileum Liver Gallbladder Large
intestine
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- 2015 Pearson Education, Inc. Figure 14.12 Peristaltic and
segmental movements of the digestive tract. (a) (b)
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- 2015 Pearson Education, Inc. Figure 14.12a Peristaltic and
segmental movements of the digestive tract. (a)
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- 2015 Pearson Education, Inc. Figure 14.12b Peristaltic and
segmental movements of the digestive tract. (b)
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- 2015 Pearson Education, Inc. Figure 14.3 Basic structure of the
alimentary canal wall. Visceral peritoneum Intrinsic nerve plexuses
Myenteric nerve plexus Submucosal nerve plexus Submucosal glands
Mucosa Surface epithelium Lamina propria Muscle layer Submucosa
Muscularis externa Serosa Longitudinal muscle layer Circular muscle
layer (visceral peritoneum) Lumen Lymphoid tissue Duct of gland
outside alimentary canal Gland in mucosa Nerve Artery Vein
Mesentery
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- 2015 Pearson Education, Inc. Figure 14.5b Peritoneal
attachments of the abdominal organs. Anus Rectum Peritoneal cavity
Mesenteries Transverse colon Duodenum Pancreas Lesser omentum
Diaphragm Liver Stomach Greater omentum Small intestine Uterus
Urinary bladder Parietal peritoneum Visceral peritoneum (b)
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- 2015 Pearson Education, Inc. Figure 14.2a Anatomy of the mouth
(oral cavity). Hard palate Oral cavity Lips (labia) Vestibule
Lingual frenulum Tongue Hyoid bone Trachea (a) Esophagus
Laryngopharynx Epiglottis Oropharynx Lingual tonsil Palatine tonsil
Uvula Soft palate Nasopharynx
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- 2015 Pearson Education, Inc. Figure 14.9 Human deciduous and
permanent teeth. (2 of 2) Incisors Canine (eyetooth) Premolars
(bicuspids) Molars Permanent teeth Third molar (wisdom tooth) (1725
yr) Second molar (1213 yr) First molar (67 yr) Second premolar
(1213 yr) First premolar (11 yr) Central (7 yr) Lateral (8 yr)
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- 2015 Pearson Education, Inc. Figure 14.10 Longitudinal section
of a molar. Crown Enamel Neck Root Dentin Pulp cavity (contains
blood vessels and nerves) Gum (gingiva) Cement Root canal
Periodontal membrane (ligament) Bone
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- 2015 Pearson Education, Inc. Homeostatic Imbalance 14.15 A baby
born with a cleft lip and palate.
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- 2015 Pearson Education, Inc. Figure 14.2b Anatomy of the mouth
(oral cavity). Hard palate Soft palate Uvula Palatine tonsil
Oropharynx Tongue (b) Upper lip Gingivae (gums)
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- 2015 Pearson Education, Inc. Figure 14.2a Anatomy of the mouth
(oral cavity). Hard palate Oral cavity Lips (labia) Vestibule
Lingual frenulum Tongue Hyoid bone Trachea (a) Esophagus
Laryngopharynx Epiglottis Oropharynx Lingual tonsil Palatine tonsil
Uvula Soft palate Nasopharynx
- Slide 15
- 2015 Pearson Education, Inc. Figure 14.14 Swallowing. Upper
esophageal sphincter contracted Bolus of food Tongue Pharynx
Epiglottis up Glottis (lumen) of larynx Upper esophageal sphincter
Larynx up Esophagus Uvula Bolus Epiglottis down (b)Upper esophageal
sphincter relaxed (c)Upper esophageal sphincter contracted Bolus
Relaxed muscles Cardioesophageal sphincter open (d)
Cardioesophageal sphincter relaxed Trachea (a)
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- 2015 Pearson Education, Inc. Figure 14.14a Swallowing. Upper
esophageal sphincter contracted Bolus of food Tongue Pharynx
Epiglottis up Glottis (lumen) of larynx Upper esophageal sphincter
Esophagus Trachea (a)
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- 2015 Pearson Education, Inc. Figure 14.14b Swallowing. Larynx
up Esophagus Uvula Bolus Epiglottis down (b) Upper esophageal
sphincter relaxed
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- 2015 Pearson Education, Inc. Figure 14.14c Swallowing. (c)Upper
esophageal sphincter contracted Bolus
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- 2015 Pearson Education, Inc. Figure 14.14d Swallowing. Relaxed
muscles Cardioesophageal sphincter open (d) Cardioesophageal
sphincter relaxed
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- 2015 Pearson Education, Inc. Figure 14.4a Anatomy of the
stomach. Esophagus Cardia Fundus Serosa Body Rugae of mucosa
Greater curvature Pyloric antrum Pyloric sphincter (valve) Duodenum
Pylorus Lesser curvature Oblique layer Circular layer Longitudinal
layer Muscularis externa (a)
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- 2015 Pearson Education, Inc. Figure 14.4b Anatomy of the
stomach. Fundus Body Rugae of mucosa Pyloric sphincter Pyloric
antrum (b)
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- 2015 Pearson Education, Inc. Figure 14.4c Anatomy of the
stomach. Pyloric sphincter Gastric pits Gastric pit Gastric gland
Surface epithelium Mucous neck cells Parietal cells Gastric glands
Chief cells (c)
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- 2015 Pearson Education, Inc. Figure 14.4d Anatomy of the
stomach. Chief cells Enteroendocrine cell (d) Pepsinogen HCI Pepsin
Parietal cells
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- 2015 Pearson Education, Inc. Figure 14.15 Peristaltic waves in
the stomach. 1 2 3 Pyloric valve closed Pyloric valve slightly
opened Pyloric valve closed Propulsion: Peristaltic waves move from
the fundus toward the pylorus. Grinding: The most vigorous
peristalsis and mixing action occur close to the pylorus. The
pyloric end of the stomach acts as a pump that delivers small
amounts of chyme into the duodenum. Retropulsion: The peristaltic
wave closes the pyloric valve, forcing most of the contents of the
pylorus backward into the stomach.
- Slide 25
- 2015 Pearson Education, Inc. Figure 14.6 The duodenum of the
small intestine and related organs. Right and left hepatic ducts
from liver Cystic duct Common hepatic duct Bile duct and sphincter
Accessory pancreatic duct Pancreas Jejunum Main pancreatic duct and
sphincter Duodenum Hepatopancreatic ampulla and sphincter Duodenal
papilla Gallbladder
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- 2015 Pearson Education, Inc. Figure 14.7 Structural
modifications of the small intestine. Blood vessels serving the
small intestine Muscle layers Villi Lumen Circular folds (plicae
circulares) Absorptive cells Lacteal Blood capillaries Lymphoid
tissue Intestinal crypt Muscularis mucosae (b)Villi Venule
Lymphatic vessel Submucosa Villus (c)Absorptive cells Microvilli
(brush border) (a) Small intestine
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- 2015 Pearson Education, Inc. Figure 14.7a Structural
modifications of the small intestine. Blood vessels serving the
small intestine Muscle layers Villi Lumen Circular folds (plicae
circulares) (a) Small intestine
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- 2015 Pearson Education, Inc. Figure 14.7b Structural
modifications of the small intestine. Absorptive cells Lacteal
Blood capillaries Lymphoid tissue Intestinal crypt Muscularis
mucosae (b)Villi Venule Lymphatic vessel Submucosa Villus
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- 2015 Pearson Education, Inc. Figure 14.7c Structural
modifications of the small intestine. (c)Absorptive cells
Microvilli (brush border)
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- 2015 Pearson Education, Inc. Figure 14.8 The large intestine.
Right colic (hepatic) flexure Transverse colon Haustrum Ascending
colon Ileum (cut) Ileocecal valve Cecum Appendix Rectum Anal canal
External anal sphincter Sigmoid colon Teniae coli Cut edge of
mesentery Descending colon Transverse mesocolon Left colic
(splenic) flexure
- Slide 31
- 2015 Pearson Education, Inc. Figure 14.9 Human deciduous and
permanent teeth. Incisors Canine (eyetooth) Molars Incisors Canine
(eyetooth) Premolars (bicuspids) Molars Permanent teeth Third molar
(wisdom tooth) (1725 yr) Second molar (1213 yr) First molar (67 yr)
Second premolar (1213 yr) First premolar (11 yr) Central (7 yr)
Lateral (8 yr) Second molar (about 2 yr) Deciduous (milk) teeth
First molar (1015 mo) (1620 mo) Lateral (810 mo) Central (68
mo)
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- 2015 Pearson Education, Inc. Figure 14.9 Human deciduous and
permanent teeth. (1 of 2) Incisors Canine (eyetooth) Molars Second
molar (about 2 yr) Deciduous (milk) teeth First molar (1015 mo)
(1620 mo) Lateral (810 mo) Central (68 mo)
- Slide 33
- 2015 Pearson Education, Inc. Figure 14.13 Flowchart of
digestion and absorption of foodstuffs. Digestion of carbohydrates
Foodstuff Enzyme(s) and source Site of action Absorption of
carbohydrates Digestion of proteins Absorption of proteins
Digestion of fats Absorption of fats Fatty acids and monoglycerides
enter the lacteals of the villi and are transported to the systemic
circulation via the lymph in the thoracic duct. (Glycerol and
short-chain fatty acids are absorbed into the capillary blood in
the villi and transported to the liver via the hepatic portal
vein.) Monoglycerides and fatty acids Glycerol and fatty acids
Pancreatic lipase Small intestine Emulsified by the detergent
action of bile salts from the liver Unemulsified fats
*Oligosaccharides consist of a few linked monosaccharides. Amino
acids enter the capillary blood in the villi and are transported to
the liver via the hepatic portal vein. Brush border enzymes
(aminopeptidase, carboxypeptidase, and dipeptidase) Amino acids
(some dipeptides and tripeptides) Small polypeptides, small
peptides Large polypeptides Protein Pepsin (stomach glands) in the
presence of HCI Stomach Small intestine The monosaccharides
glucose, galactose, and fructose enter the capillary blood in the
villi and are transported to the liver via the hepatic portal vein.
Brush border enzymes in small intestine (dextrinase, glucoamylase,
lactase, maltase, and sucrase) Small intestine GalactoseGlucose
Fructose LactoseMaltoseSucrose Oligosaccharides* and disaccharides
Starch and disaccharides Salivary amylase Pancreatic amylase Mouth
Small intestine Pancreatic enzymes (trypsin, chymotrypsin,
carboxypeptidase)
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- 2015 Pearson Education, Inc. Figure 14.13 Flowchart of
digestion and absorption of foodstuffs. (1 of 3) Digestion of
carbohydrates Foodstuff Enzyme(s) and source Site of action
Absorption of carbohydrates The monosaccharides glucose, galactose,
and fructose enter the capillary blood in the villi and are
transported to the liver via the hepatic portal vein. Brush border
enzymes in small intestine (dextrinase, glucoamylase, lactase,
maltase, and sucrase) Small intestine GalactoseGlucose Fructose
LactoseMaltose Sucrose Oligosaccharides* and disaccharides Starch
and disaccharides Salivary amylase Pancreatic amylase Mouth Small
intestine *Oligosaccharides consist of a few linked
monosaccharides.
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- 2015 Pearson Education, Inc. Figure 14.13 Flowchart of
digestion and absorption of foodstuffs. (2 of 3) Digestion of
proteins Absorption of proteins Foodstuff Enzyme(s) and source Site
of action Brush border enzymes (aminopeptidase, carboxypeptidase,
and dipeptidase) Amino acids (some dipeptides and tripeptides)
Small polypeptides, small peptides Large polypeptides Protein
Pepsin (stomach glands) in the presence of HCI Stomach Small
intestine Pancreatic enzymes (trypsin, chymotrypsin,
carboxypeptidase) Amino acids enter the capillary blood in the
villi and are transported to the liver via the hepatic portal
vein.
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- 2015 Pearson Education, Inc. Figure 14.13 Flowchart of
digestion and absorption of foodstuffs. (3 of 3) Digestion of fats
Absorption of fats Foodstuff Enzyme(s) and source Site of action
Fatty acids and monoglycerides enter the lacteals of the villi and
are transported to the systemic circulation via the lymph in the
thoracic duct. (Glycerol and short-chain fatty acids are absorbed
into the capillary blood in the villi and transported to the liver
via the hepatic portal vein.) Monoglycerides and fatty acids
Glycerol and fatty acids Pancreatic lipase Small intestine
Emulsified by the detergent action of bile salts from the liver
Unemulsified fats
- Slide 37
- 2015 Pearson Education, Inc. Figure 14.16 Regulation of
pancreatic juice and bile secretion and release. 1 2 3 4 5 Chyme
entering duodenum causes duodenal entero- endocrine cells to
release cholecytokinin (CCK) and secretin. CCK (red dots) and
secretin (blue dots) enter the bloodstream. Upon reaching the
pancreas, CCK induces secretion of enzyme-rich pancreatic juice;
secretin causes secretion of bicarbonate-rich pancreatic juice.
Secretin causes the liver to secrete more bile; CCK stimulates the
gallbladder to release stored bile and the hepato- pancreatic
sphincter to relax (allows bile from both sources to enter the
duodenum). Stimulation by vagal nerve fibers cause release of
pancreatic juice and weak contractions of the gallbladder.
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- 2015 Pearson Education, Inc. Table 14.1 Hormones and
Hormonelike Products That Act in Digestion (1 of 2).
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- 2015 Pearson Education, Inc. Table 14.1 Hormones and
Hormonelike Products That Act in Digestion (2 of 2).
- Slide 40
- 2015 Pearson Education, Inc. A Closer Look 14.1 Peptic Ulcers:
Something Is Eating at Me. Bacteria Mucosa layer of stomach (b) H.
pylori bacteria(a) A peptic ulcer lesion
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- 2015 Pearson Education, Inc. A Closer Look 14.1a Peptic Ulcers:
Something Is Eating at Me. (a) A peptic ulcer lesion
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- 2015 Pearson Education, Inc. A Closer Look 14.1b Peptic Ulcers:
Something Is Eating at Me. Bacteria Mucosa layer of stomach (b) H.
pylori bacteria
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- 2015 Pearson Education, Inc. Table 14.2 Five Basic Food Groups
and Some of Their Major Nutrients (1 of 2).
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- 2015 Pearson Education, Inc. Table 14.2 Five Basic Food Groups
and Some of Their Major Nutrients (2 of 2).
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- 2015 Pearson Education, Inc. Figure 14.17 Two visual food
guides. Red meat, butter: use sparingly Vegetables in abundance
Whole-grain foods at most meals Daily exercise and weight control
Plant oils at most meals Fruits: 23 servings Nuts, legumes: 13
servings Fish, poultry, eggs: 02 servings Dairy or calcium
supplement: 12 servings White rice, white bread, potatoes, pasta,
sweets: use sparingly (a)Healthy Eating Pyramid (b)USDAs
MyPlate
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- 2015 Pearson Education, Inc. Figure 14.17a Two visual food
guides. Red meat, butter: use sparingly Vegetables in abundance
Whole-grain foods at most meals Daily exercise and weight control
Plant oils at most meals Fruits: 23 servings Nuts, legumes: 13
servings Fish, poultry, eggs: 02 servings Dairy or calcium
supplement: 12 servings White rice, white bread, potatoes, pasta,
sweets: use sparingly (a) Healthy Eating Pyramid
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- 2015 Pearson Education, Inc. Figure 14.17b Two visual food
guides. (b) USDAs MyPlate
- Slide 48
- 2015 Pearson Education, Inc. Figure 14.18 The eight essential
amino acids. Tryptophan Methionine Beans and other legumes Valine
Threonine Phenylalanine Leucine Isoleucine Lysine Corn and other
grains
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- 2015 Pearson Education, Inc. Figure 14.19 Summary equation for
cellular respiration. C 6 H 12 O 6 + O2O2 6 CO 2 6 + 6 H2OH2O + ATP
Glucose Oxygen gas Carbon dioxide Water Energy
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- 2015 Pearson Education, Inc. Figure 14.20 During cellular
respiration, ATP is formed in the cytosol and in the mitochondria.
CO 2 H2OH2O 1 2 3 Chemical energy (high-energy electrons) Chemical
energy Electron transport chain and oxidative phosphorylation
Mitochondrion Via oxidative phosphorylation 28 ATP 2 ATP Glucose
Pyruvic acid Cytosol of cell Mitochondrial cristae During
glycolysis, each glucose molecule is broken down into two molecules
of pyruvic acid as hydrogen atoms containing high-energy electrons
are removed. Via substrate-level phosphorylation 2 ATP The pyruvic
acid enters the mitochondrion, where Krebs cycle enzymes remove
more hydrogen atoms and decompose it to CO 2. During glycolysis and
the Krebs cycle, small amounts of ATP are formed. Energy-rich
electrons picked up by coenzymes are transferred to the electron
transport chain, built into the cristae membrane. The electron
transport chain carries out oxidative phosphorylation, which
accounts for most of the ATP generated by cellular respiration, and
finally unites the removed hydrogen with oxygen to form water.
Krebs cycle Glycolysis
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- 2015 Pearson Education, Inc. Figure 14.21 Electron transport
chain versus one-step reduction of oxygen. NADHNAD + + H+H+ 2e ee
O2O2 Energy released as heat and light Energy released and now
available for making ATP Protein carriers of the electron transport
chain Electron flow (b)(a)
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- 2015 Pearson Education, Inc. Figure 14.21a Electron transport
chain versus one-step reduction of oxygen. NADH NAD + + H+H+ 2e ee
O2O2 Energy released and now available for making ATP Protein
carriers of the electron transport chain Electron flow (a)
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- 2015 Pearson Education, Inc. Figure 14.21b Electron transport
chain versus one-step reduction of oxygen. Energy released as heat
and light (b)
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- 2015 Pearson Education, Inc. Figure 14.22 Metabolism by body
cells. (a)Carbohydrates: polysaccharides, disaccharides; composed
of simple sugars (monosaccharides) Cellular uses To capillary
Polysaccharides GI digestion to simple sugars Monosaccharides ATP
Glycogen and fat broken down for ATP formation Excess stored as
glycogen or fat Broken down to glucose and released to blood ATP
Fats are the primary fuels in many cells Fats build myelin sheaths
and cell membranes Cellular uses Insulation and fat cushions to
protect body organs Metabolized by liver to acetic acid, etc. GI
digestion to fatty acids and glycerol Lipid (fat) Fatty acids
Glycerol (b)Fats: composed of 1 glycerol molecule and 3 fatty
acids; triglycerides (c)Proteins: polymers of amino acids Protein
GI digestion to amino acids Normally infrequent Amino acids
Cellular uses ATP ATP formation if inadequate glucose and fats or
if essential amino acids are lacking Functional proteins (enzymes,
antibodies, hemoglobin, etc.) Structural proteins (connective
tissue fibers, muscle proteins, etc.) Carbon dioxide Water ATP
Cellular metabolic furnace: Krebs cycle and electron transport
chain Monosaccharides Fatty acids Amino acids (amine first removed
and combined with CO 2 by the liver to form urea) (d)ATP formation
(fueling the metabolic furnace): all categories of food can be
oxidized to provide energy molecules (ATP)
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- 2015 Pearson Education, Inc. Figure 14.22a Metabolism by body
cells. (a)Carbohydrates: polysaccharides, disaccharides; composed
of simple sugars (monosaccharides) Cellular uses To capillary
Polysaccharides GI digestion to simple sugars Monosaccharides ATP
Glycogen and fat broken down for ATP formation Excess stored as
glycogen or fat Broken down to glucose and released to blood
- Slide 56
- 2015 Pearson Education, Inc. Figure 14.22b Metabolism by body
cells. ATP Fats are the primary fuels in many cells Fats build
myelin sheaths and cell membranes Cellular uses Insulation and fat
cushions to protect body organs Metabolized by liver to acetic
acid, etc. GI digestion to fatty acids and glycerol Lipid (fat)
Fatty acids Glycerol (b)Fats: composed of 1 glycerol molecule and 3
fatty acids; triglycerides
- Slide 57
- 2015 Pearson Education, Inc. Figure 14.22c Metabolism by body
cells. (c) Proteins: polymers of amino acids Protein GI digestion
to amino acids Normally infrequent Amino acids Cellular uses ATP
ATP formation if inadequate glucose and fats or if essential amino
acids are lacking Functional proteins (enzymes, antibodies,
hemoglobin, etc.) Structural proteins (connective tissue fibers,
muscle proteins, etc.)
- Slide 58
- 2015 Pearson Education, Inc. Figure 14.22d Metabolism by body
cells. Carbon dioxide Water ATP Cellular metabolic furnace: Krebs
cycle and electron transport chain Monosaccharides Fatty acids
Amino acids (amine first removed and combined with CO 2 by the
liver to form urea) (d)ATP formation (fueling the metabolic
furnace): all categories of food can be oxidized to provide energy
molecules (ATP)
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- 2015 Pearson Education, Inc. Figure 14.23 Metabolic events
occurring in the liver as blood glucose levels rise and fall.
HOMEOSTATIC BLOOD SUGAR IMBALANCE Glycogenesis: Glucose converted
to glycogen and stored Gluconeogenesis: Amino acids and fats
converted to glucose Glycogenolysis: Stored glycogen converted to
glucose Stimulus: Falling blood glucose level Stimulus: Rising
blood glucose level
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- 2015 Pearson Education, Inc. Table 14.3 Factors Determining the
Basal Metabolic Rate (BMR).
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- 2015 Pearson Education, Inc. Figure 14.24 Mechanisms of body
temperature regulation. HOMEOSTASIS = normal body temperature
(35.6C37.8C) IMBALANCE Skin blood vessels dilate: Capillaries
become flushed with warm blood; heat radiates from skin surface
Body temperature decreases: Blood temperature declines and
hypothalamus heat-loss center shuts off Sweat glands activated:
Secrete perspiration, which is vaporized by body heat, helping to
cool the body Activates heat-loss center in hypothalamus Blood
warmer than hypothalamic set point Stimulus: Increased body
temperature (e.g., when exercising or the climate is hot) Skin
blood vessels constrict: Blood is diverted from skin capillaries
and withdrawn to deeper tissues; minimizes overall heat loss from
skin surface Body temperature increases: Blood temperature rises
and hypothalamus heat-promoting center shuts off Skeletal muscles
activated when more heat must be generated; shivering begins Blood
cooler than hypothalamic set point Activates heat- promoting center
in hypothalamus Stimulus: Decreased body temperature (e.g., due to
cold environmental temperatures)
- Slide 62
- 2015 Pearson Education, Inc. Figure 14.24 Mechanisms of body
temperature regulation. (1 of 2) HOMEOSTASIS = normal body
temperature (35.6C37.8C) IMBALANCE Skin blood vessels dilate:
Capillaries become flushed with warm blood; heat radiates from skin
surface Body temperature decreases: Blood temperature declines and
hypothalamus heat-loss center shuts off Sweat glands activated:
Secrete perspiration, which is vaporized by body heat, helping to
cool the body Activates heat-loss center in hypothalamus Blood
warmer than hypothalamic set point Stimulus: Increased body
temperature (e.g., when exercising or the climate is hot)
- Slide 63
- 2015 Pearson Education, Inc. Figure 14.24 Mechanisms of body
temperature regulation. (2 of 2) HOMEOSTASIS = normal body
temperature (35.6C37.8C) IMBALANCE Skin blood vessels constrict:
Blood is diverted from skin capillaries and withdrawn to deeper
tissues; minimizes overall heat loss from skin surface Body
temperature increases: Blood temperature rises and hypothalamus
heat-promoting center shuts off Skeletal muscles activated when
more heat must be generated; shivering begins Blood cooler than
hypothalamic set point Activates heat- promoting center in
hypothalamus Stimulus: Decreased body temperature (e.g., due to
cold environmental temperatures)
- Slide 64
- 2015 Pearson Education, Inc. A Closer Look 14.2 Obesity.
- Slide 65
- 2015 Pearson Education, Inc. Systems in Sync 14.1 Homestatic
Relationships between the Digestive System and Other Body Systems.
Digestive System Liver removes hormones from blood, ending their
activity; digestive system provides nutrients needed for energy
fuel, growth, and repair; pancreas has hormone-producing cells
Local hormones help regulate digestive function Digestive system
provides nutrients for normal functioning; HCI of stomach provides
nonspecific protection against bacteria Lacteals drain fatty lymph
from digestive tract organs and convey it to blood; Peyers patches
and lymphoid tissue in mesentery house macrophages and immune cells
that protect digestive tract organs against infection Digestive
system provides nutrients for energy fuel, growth, and repair
Kidneys transform vitamin D to its active form, which is needed for
calcium absorption; excrete some bilirubin produced by the liver
Digestive system provides nutrients for energy fuel, growth, and
repair; liver removes lactic acid, resulting from muscle activity,
from the blood Skeletal muscles activity increases contractions of
GI tract Digestive system produces nutrients for normal neural
functioning Neural controls of digestive function; in general,
para- sympathetic fibers accelerate and sympathetic fibers inhibit
digestive activity; reflex and voluntary controls of defecation
Digestive system provides nutrients for energy metabolism, growth,
and repair Respiratory system provides oxygen and carries away
carbon dioxide produced by digestive system organs Digestive system
provides nutrients to heart and blood vessels; absorbs iron needed
for hemoglobin synthesis; absorbs water necessary for normal blood
volume Cardiovascular system transports nutrients absorbed by
alimentary canal to all tissues of the body; distributes hormones
of the digestive tract Digestive system provides nutrients for
energy fuel, growth, and repair and extra nutrition needed to
support fetal growth Digestive system provides nutrients for energy
fuel, growth, and repair; supplies fats that provide insulation in
the dermal and subcutaneous tissues The skin synthesizes vitamin D
needed for calcium absorption from the intestine; protects by
enclosure Digestive system provides nutrients for energy fuel,
growth, and repair; absorbs calcium needed for bone salts Skeletal
system protects some digestive organs by bone; cavities store some
nutrients (e.g., calcium, fats) Endocrine System Lymphatic
System/Immunity Urinary System Muscular System Nervous System
Respiratory System Cardiovascular System Reproductive System
Integumentary System Skeletal System