1. What can you tell me about this compound?

5. Chapter 2 Apply Problem #5 If an aqueous (water) extract does not work but one using benzene as the solvent does have an effect, what might you conclude about the chemical nature of the hormone? explain. Hormone is lipophilic or nonpolar. Explain: Hormone dissolves in benzene, an organic solvent (nonpolar) but doesn’t dissolve in polar solvent (water).

6. Proteins The other main component of the cell membrane.

7. Functions of Protein Transport channels pumps carriers Communication receptors signaling molecules hormones “flags” Enzymes Structure Collagen, keratin, bone matrix, intracellular microtubules Antibodies Movement Muscle cells are 20% actin (protein)

8. Amino Acid Structure R group can be polar or nonpolar big or small charged – acidic or basic

9. Amino acids – R groups

11. Amino acids

12. Peptides – dipetide formation Formation from amino acids: FOX fig 2.25 + H 2 O dipeptide cysteine glycine

13. Peptides Tripeptide - glutathione glycine cysteine glutamic acid + dipeptide

14. Protein Four levels of structural organization Primary structure Amino acid sequence gly-cys-ala-trp-glu-asp-gly-tyr-cys-ala- Secondary structure Sections of peptide chain coil or fold into either: Alpha helix Beta sheet Tertiary structure Whole peptide chain (protein) folds/coils around itself H bonding, sulfide bridges, non-polar/non-polar interactions Quaternary structure More than one peptide chain associated with each other

15. Proteins (FOX fig 2.26)

16. Tertiary Structure (FOX fig 2.27)

17. Protein Synthesis within the context of homeostasis. Objectives Review how proteins are synthesized Give an example of an effector action Review key organelles Preview regulation of ions Preview endocrine signaling

18. Protein Synthesis within the context of homeostasis. Negative Feedback: Sensor detects a change parameter’s level Control unit activates an effector Effect is to return parameter to normal level Typical effector action is to make a protein Another effect is to activate a protein protein activation can lead to the release of hormone or neurotransmitter protein activated is often an enzyme

19. Protein Synthesis Example: Aldosterone What is aldosterone? Steroid hormone produced by adrenal cortex It is a mineralocorticoid Promotes the retention of Na + and loss of K + What induces the release of aldosterone? Low Na + and high K + Target organ? Kidney – epithelial cells of distal tubule

20. plasma membrane aldosterone carrier protein (albumin) target cell

21. Aldosterone on carrier approaches the cell membrane

22. Aldosterone diffuses readily into the lipophilic membrane.

23. Aldosterone receptor picks up aldosterone and moves it into the cell. aldosterone receptor

24. Aldosterone receptor complex heads towards the nucleus.

25. know cell structures

28. Translation (FOX fig 3.24)

29. Microtubules aid movement of vesicles to cell membrane

30. Pumps/channels are degraded in lysosomes when no longer needed

31. Carbohydrates Contain CH 2 O 6 carbon sugars – C 6 H 12 O 6 glucose (glu) fructose (fru) galactose (gal) 5 carbon sugars – C 5 H 10 O 5 ribose DNA RNA

32. Carbohydrates If glucose and galactose have the same formula (C 6 H 12 O 6 ) what is the difference? structural isomers (FOX fig 2.13) glucose reversed in galactose

33. Ribose Found in DNA and RNA (FOX fig 2.29) Found in ATP (FOX fig 4.15) Found in NADH and FADH 2 (FOX fig 4.17) ribose removed in DNA

34. Disaccharides (FOX fig 2.15)

35. Disaccharide short hand Sucrose = glu-fru Lactose = glu-gal Maltose = glu-glu What’s this? glu-glu-glu-glu-glu-glu-glu-glu-glu-

36. Polysaccharide glu-glu-glu-glu-glu-glu-glu-glu-glu- Starch linear chains of glucose found in plants Glycogen densely branched chains of glucose found in humans Cellulose chains of glucose (tend to stack into sheets) found in plants

37. Why can’t we digest cellulose? First how do we digest starch? Amylase (enzyme) takes long chains of glucose and breaks off disaccharide pieces. What are the characteristics of enzymes?

38. Enzymes Biological catalysts either make reactions happen or make reactions happen faster Names end in –ase starch (aka amylose) is digested with amylase Can be classified according to activity phosphatase – removes phosphate groups kinase – adds phosphate groups Proteins

39. Characteristics of Protein Interactions Such as enzyme/substrate or receptor/hormone Binding site that is specific The substrate/hormone is called the ligand (The ligand is the thing that binds to the protein) What is the ligand for the aldosterone receptor? What is the ligand for amylase? The rate of reaction or activity is dependent on binding characteristics.

40. Binding characteristics Specificity – binding site designed for one type of ligand Affinity – strength of bond between ligand and binding site Competition – two or more ligands competing for one binding site Saturation – occupation of binding sites thousands of enzymes/receptors per cell graph (FOX fig 4.6)

41. Saturation (FOX fig 4.6)

42. Why can’t we digest cellulose? starch has alpha linkages cellulose has beta linkages Example of ENZYME SPECIFICITY!!

43. Functions of Carbohydrates Fuel Signaling Molecule Ribose is component of: DNA RNA ATP NAD/FADH Digestive Regulation Fiber normalize transit time Fiber decreases cholesterol, TAG and LDL