Anatomy and Physiology by Rod R Seeley 6th edition chapter 25 power-point

1
Anatomy and Physiology, Sixth Edition
Rod R. SeeleyIdaho State University Trent D.
StephensIdaho State University Philip
TatePhoenix College
Chapter 25 Lecture Outline
See PowerPoint Image Slides for all figures and
tables pre-inserted into PowerPoint without notes.
Copyright The McGraw-Hill Companies, Inc.
Permission required for reproduction or display.
2
Chapter 25

• Nutrition, Metabolism,
• Temperature Regulation

3
Nutrients

• Chemicals used by body
• Classes
• Carbohydrates, proteins, lipids, vitamins,
  minerals, water
• Food Guide Pyramid
• USDA recommends
• Kilocalories
• Measure of energy supplied by food and released
  through metabolism

4
Carbohydrates

• Monosaccharides
• Include glucose, fructose, galactose
• Disaccharides
• Include sucrose, maltose, lactose
• Polysaccharides (complex)
• Include starch, glycogen, cellulose
• Disaccharides and Polysaccharides
• Converted to glucose (used for energy or stored
  as glycogen or fats)

5
Lipids

• Triglycerides (95) Used for energy to produce
  ATP or stored in adipose tissue, liver
• Saturated fats Meat fats, whole milk, cheese,
  eggs
• Unsaturated fats Olive and peanut oil
• Cholesterol Steroid found in liver, egg yolks
  but not found in plants
• Phospholipids Major components of plasma
  membranes

6
Proteins

• Chains of amino acids
• Kinds
• Essential Must be obtained in diet
• Nonessential Body can synthesize
• Functions
• Protection (antibodies), regulation (enzymes,
  hormones), structure (collagen), muscle
  contraction (actin, myosin), transportation
  (hemoglobin, ion channels)

7
Recommended Amounts

• Carbohydrates
• 60 of daily intake of kilocalories
• Lipids
• 30 or less of total daily kilocalories
• Proteins
• 10 of total kilocalories per day

8
Vitamins

• Function as coenzymes or parts of coenzymes
• Organic molecules that exist in minute quantities
  in food
• Essential vitamins must be obtained by diet
• Classifications
• Fat soluble Vitamins A,D,E,K
• Water-soluble B and C

9
Minerals

• Inorganic
• Necessary for normal metabolic functions
• Functions
• Establish resting membrane potentials, generate
  action potentials, add strength to bones and
  teeth, buffers, involved in osmotic balance
• Obtained from animal and plant sources

10
Metabolism

• Total of all chemical changes that occur in body
• Anabolism Energy-requiring process where small
  molecules joined to form larger molecules
• Catabolism Energy-releasing process where large
  molecules broken down to smaller
• Energy in carbohydrates, lipids, proteins is used
  to produce ATP through oxidation-reduction
  reactions

11
Catabolic and Anabolic Reactions
12
Cellular Metabolism
13
Carbohydrate Metabolism

• Glycolysis
• Breakdown of glucose into 2 pyruvic acid
  molecules
• Phases
• Input of ATP
• Sugar cleavage
• NADH production
• ATP and pyruvic acid production

14
Glycolysis
15
Glycolysis
16
Anaerobic Respiration

• Breakdown of glucose in absence of oxygen
• Produces 2 molecules of lactic acid and 2
  molecules of ATP
• Phases
• Glycolysis
• Lactic acid formation
• Cori cycle
• Process of converting lactic acid to glucose

17
Aerobic Respiration

• Breakdown of glucose in presence of oxygen to
  produce carbon dioxide, water, 38 ATP molecules
• Most of ATP molecules to sustain life are
  produced this way
• Phases
• Glycolysis, acetyl-CoA formation, citric acid
  cycle, electron-transport chain

18
Aerobic Respiration
19
Electron-Transport Chain
20
Lipid Metabolism

• Adipose triglycerides are broken down and
  released as free fatty acids
• Free fatty acids are taken up by cells and broken
  down by beta-oxidation into acetyl-CoA which
• Can enter citric acid cycle
• Can be converted to ketone bodies

21
Protein Metabolism

• New amino acids are formed by transamination,
  transfer of an amine group to keto acid
• Amino acids are used to synthesize proteins
• If used for energy, ammonia is produced as a
  by-product of oxidative deamination
• Ammonia is converted to urea and excreted

22
Amino Acid Metabolism

• Once absorbed in body, amino acids quickly taken
  up by cells
• Amino acids are used to synthesize proteins or as
  a source of energy
• Amino acids not stored in body

23
Amino Acid Reactions
24
Interconversion of Nutrient Molecules

• Glycogenesis
• Excess glucose used to form glycogen
• Lipogenesis
• When glycogen stores filled, glucose and amino
  acids used to synthesize lipids
• Glycogenolysis
• Breakdown of glycogen to glucose
• Gluconeogenesis
• Formation of glucose from amino acids and glycerol

25
Interconversion of Nutrient Molecules
26
Metabolic States

• Absorptive state
• Period immediately after eating when nutrients
  absorbed through intestinal wall into circulatory
  and lymphatic systems (about 4 hours after each
  meal)
• Postabsorptive state
• Occurs late in morning, afternoon, night after
  absorptive state concluded
• Blood glucose levels maintained by conversion of
  other molecules to glucose

27
Absorptive State
28
Postabsorptive State
29
Metabolic Rate

• Total amount of energy produced and used by body
  per unit of time
• Estimated by amount of oxygen used per minute
• Components
• Basal metabolic rate
• Energy used at rest, 60 of metabolic rate
• Thermic effect of food
• Energy used to digest and absorb food, 10
• Muscular activity
• Energy used for muscle contraction, 30

30
Body Temperature Regulation

• A balance between heat gain and loss
• Heat is produced through metabolism
• Heat is exchanged through radiation, conduction,
  convection, evaporation
• The greater the temperature difference between
  body and environment, the greater the rate of
  heat exchange
• Regulated by a set point in hypothalamus

31
Heat Exchange
32
Temperature Regulation