1. Copyright © 2009 Pearson Education, Inc. © 2013 Pearson Education, Inc. PowerPoint Lecture prepared by Jill Feinstein Richland Community College Fourth Edition BIOLOGY Science for Life | with Physiology Colleen Belk Virginia Borden Maier Chapter 3 Is it Possible to Supplement Your Way to Better Health? Nutrients and Membrane Transport

2. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Nutrients: substances in foods that provide structural materials or energy  Macronutrients: nutrients that are required in large amounts  Water  Adults need about 3 liters per day  Too little leads to dehydration  Maintains blood pressure  Involved in all cellular activities

3. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Carbohydrates: main energy source  Simple sugars (glucose) enter our system quickly  Complex carbohydrates (branching chains of simple sugars) are digested more slowly  Starch: complex carbohydrate from plants  Glycogen: complex carbohydrate from animals

4. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Processed food  Food that has undergo processing that has stripped it of its nutritional value  Whole foods  Foods that have not been stripped of their nutrition  Fiber: indigestible complex carbohydrates  Essential for large intestine function  Lowers cholesterol and reduces cancer risk

5. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Proteins  Polymers of amino acids  Essential amino acids: we cannot make these ourselves; must obtain them from food  Complete proteins: contain all the essential amino acids we need  Plant proteins can be combined to make them complete.

6. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Fats  Energy storage molecules  Acts as a cushion and insulator  Consist of a glycerol attached to fatty acid tails  Essential fatty acids: we cannot make these ourselves (e.g., omega-3 and omega-6)

7. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Fats  Saturated fats: fatty acid carbons are bound to as much hydrogen as possible  Lack double bonds  Solid at room temperature  Most animal fats are saturated

8. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Fats  Unsaturated fats are not bound to as much hydrogen as possible  Contain double bonds which give kinks in the tails  Liquid at room temperature  Most plant fats (oils) are unsaturated or polyunsaturated

9. © 2013 Pearson Education, Inc. 1 Nutrients - Macronutrients  Fats  Polyunsaturated fats  Have many double bonds preventing it from tightly packing  Hydrogenation  Process that adds hydrogen atoms to unsaturated fats to make it a solid  Trans fats are produced by incomplete hydrogenation and not beneficial  May be linked to an increased risk of heart disease and diabetes

10. © 2013 Pearson Education, Inc. 1 Nutrients - Micronutrients  Micronutrients: nutrients that are needed in small quantities  Vitamins: Table 3.1 lists the various vitamins  organic substances which usually function as coenzymes  Vitamin D the only one we can synthesize  Water-soluble vitamins  Not stored in the body and typically the cause of deficiencies  Fat-soluble vitamins  Stored in fat and can cause problems in excess

11. © 2013 Pearson Education, Inc. 1 Nutrients - Micronutrients  Minerals: inorganic substances  Do not contain carbon but essential for cell functions  Must be supplied through diet and are water soluble  Calcium is a very important mineral that plays a role in bones, clotting, muscle contraction and nerve impulses  Table 3.2 lists the various minerals and their functions

12. © 2013 Pearson Education, Inc. 1 Nutrients - Micronutrients  Antioxidants  Found in whole foods  Protect cells from damage by free radicals  Free radicals can damage DNA and cell membranes  Table 3.3 describes food sources of antioxidants

13. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Nutrients have to move across the cell membrane in order to be used by the cell.  Plasma membrane is composed of a phospholipid bilayer & is differentially permeable

14. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Diffusion: movement of molecules from area of high concentration to low concentration  Passive transport: diffusion of small hydrophobic molecules without energy

15. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Facilitated diffusion: transport of hydrophilic and charged molecules across the membrane.  Uses proteins embedded in the membrane  No input of energy required

16. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Osmosis: movement of water across a membrane, from high to low concentration.  When an animal cell is placed in salt water it will shrivel  When an animal cell is placed in distilled water it will swell and burst

17. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Active transport  Uses proteins to move molecules from low to high concentration  Powered by energy from ATP

18. © 2013 Pearson Education, Inc. 2 Transport Across Membranes  Exocytosis: a membrane-bound vesicle fuses with the membrane and expels the large molecule  Endocytosis: a vesicle forms around a large molecule and brings it into the cell

19. © 2013 Pearson Education, Inc. AnimationAnimation: Passive and Active Transport Click “Go to Animation” / Click “Play”

20. © 2013 Pearson Education, Inc. AnimationAnimation: Exocytosis and Endocytosis Click “Go to Animation” / Click “Play”

21. © 2013 Pearson Education, Inc. BioFlix: Membrane TransportMembrane Transport

22. © 2013 Pearson Education, Inc. 2 You are what you eat  Food is digested into building blocks used by cells for various functions and structures

23. © 2013 Pearson Education, Inc. What serves as the major source of energy for cells?  water molecules  carbohydrates  dietary fiber  proteins

24. © 2013 Pearson Education, Inc. What serves as the major source of energy for cells?  water molecules  carbohydrates  dietary fiber  proteins

25. © 2013 Pearson Education, Inc. Which of the following describes a processed food?  foods that have been stripped of most of their nutritional value  foods that have not been stripped of their nutritional value  foods that are also called roughage and cannot be digested  foods that have additional vitamins and minerals added

26. © 2013 Pearson Education, Inc. Which of the following describes a processed food?  foods that have been stripped of most of their nutritional value  foods that have not been stripped of their nutritional value  foods that are also called roughage and cannot be digested  foods that have additional vitamins and minerals added

27. © 2013 Pearson Education, Inc. A fatty acid tail contains carbon that is double bonded to hydrogen. Which of the following statements correctly describes this structure?  This is an example of a saturated fat.  The double bonds flatten the structure.  This is an unsaturated fat and would be liquid at room temperature.  This would be a solid at room temperature.

28. © 2013 Pearson Education, Inc. A fatty acid tail contains carbon that is double bonded to hydrogen. Which of the following statements correctly describes this structure?  This is an example of a saturated fat.  The double bonds flatten the structure.  This is an unsaturated fat and would be liquid at room temperature.  This would be a solid at room temperature.

29. © 2013 Pearson Education, Inc. What is the only vitamin our cells can synthesize?  vitamin A  vitamin B  vitamin C  vitamin D

30. © 2013 Pearson Education, Inc. What is the only vitamin our cells can synthesize?  vitamin A  vitamin B  vitamin C  vitamin D

31. © 2013 Pearson Education, Inc. Charged amino acids enter the cell through _____.  passive diffusion  osmosis  facilitated diffusion  exocytosis

32. © 2013 Pearson Education, Inc. Charged amino acids enter the cell through _____.  passive diffusion  osmosis  facilitated diffusion  exocytosis

33. © 2013 Pearson Education, Inc. If the solute concentration is higher outside the cell, then  osmosis will cause water to move into the cell.  osmosis will cause water to move out of the cell.  osmosis will not cause any water to move.  osmosis will cause the to burst.

34. © 2013 Pearson Education, Inc. If the solute concentration is higher outside the cell, then  osmosis will cause water to move into the cell.  osmosis will cause water to move out of the cell.  osmosis will not cause any water to move.  osmosis will cause the to burst.

35. © 2013 Pearson Education, Inc. Which of the following statements is correct?  K + will move from high concentration to low concentration; ATP is used.  K + will move from low concentration to high concentration; ATP is used.  K + will move from high concentration to low concentration; ATP is not used.  K + will move from low concentration to high concentration; ATP is not used.

36. © 2013 Pearson Education, Inc. Which of the following statements is correct?  K + will move from high concentration to low concentration; ATP is used.  K + will move from low concentration to high concentration; ATP is used.  K + will move from high concentration to low concentration; ATP is not used.  K + will move from low concentration to high concentration; ATP is not used.