BIOLOGY 111. CHAPTER 3: Life's Components: Biological Molecules

Transcription

1 BIOLOGY 111 CHAPTER 3: Life's Components: Biological Molecules

2 Life s Components: Biological Molecules 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

3 Biological Molecules: Carbon s place in the living world Chemical Formulas Chemical Formulas are often used to show which atoms make up specific molecules Propane Methane Letters are used to indicate specific atoms, and lines represent chemical bonds to other atoms

4 Biological Molecules: Carbon s place in the living world Chemical Formulas The number and types of atoms in a molecule determine its chemical properties. Formulas reveal this information Propane Methane The Chemical Properties of a molecule are also determined by the number and arrangement of electrons.

5 Life s Components: Biological Molecules: 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

6 Biological Molecules: Carbon s place in the living world Organic Chemistry: Organic Chemistry is the chemistry of molecules that use carbon, (C), as their central, structural building block Propane Methane Carbon has 4 valence electrons, so it will always want to gain 4 more electrons by forming chemical bonds.

7 Biological Molecules: Carbon s place in the living world Organic Chemistry: Organic Chemistry is the chemistry of molecules that use carbon, (C), as their central, structural building block Carbon has 4 valence electrons, so it will always want to gain 4 more electrons by forming chemical bonds.

8 Biological Molecules: Carbon s place in the living world Organic Chemistry: Valence electrons are electrons in the outermost shell of an atom they are the electrons that participate in the formation of chemical bonds. Most atoms need 8 valence electrons to become stable Carbon has 4 valence electrons, so it will always want to gain 4 more electrons by forming chemical bonds.

9 Life s Components: Biological Molecules 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

10 Life s Components: Biological Molecules 3.2 Functional Groups

11 Biological Molecules: Types of Biological Molecules Hydrocarbons: Hydrocarbons only have Hydrogen and Carbon atoms. Hydrocarbons have NO functional groups Propane Methane Hydrocarbons tend to be Nonpolar molecules they do not mix well with water.

12 Biological Molecules: Types of Biological Molecules Hydrocarbons: Hydrocarbons only have Hydrogen and Carbon atoms. Hydrocarbons have NO functional groups Propane Methane If functional groups are added to hydrocarbons, other types of molecules can be formed

13 Biological Molecules: Functional Groups The Carboxyl Group (-COOH) is found on fatty acids and amino acids

14 Biological Molecules: Functional Groups The Carboxyl Group (-COOH) is found on fatty acids and amino acids Fatty Acid Amino Acid

15 Biological Molecules: Functional Groups The Hydroxyl Group (-OH) is found on Carbohydrates and Alcohols Carbohydrate Alcohol

16 Biological Molecules: Functional Groups The Amino Group (-NH 2 ) is found on amino acids Amino Acid

17 Biological Molecules: Functional Groups The Phosphate Group (-PO 4 ) is found on Nucleic acids and ATP ATP Nucleic Acid

18 Life s Components: Biological Molecules 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

19 Life s Components: Biological Molecules 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

20 Biological Molecules: Monomers and Polymers Monosaccharaides, amino acids and nucleotides are all monomers that can exist in polymer chains.

21 Biological Molecules: Monomers and Polymers Monosaccharaides, amino acids and nucleotides are all monomers that can exist in polymer chains.

22 Biological Molecules: Carbohydrates: Carbohydrates have Carbon (C), Hydrogen (H) and Oxygen (O) atoms. Are a primary source of energy Can be used to store energy Can be used for structural purposes in cells Carbohydrates are usually polar Glucose

23 Biological Molecules: 3.2 Functional Groups Carbohydrates: Can exist as monomers (monosaccharides) or polymers as (polysaccharides)

24 Biological Molecules: Carbohydrates: Simple Carbohydrates: Monosaccharides and Disaccharides Monosaccharides: (best available energy sources) Glucose Fructose Disaccharides: (when 2 monosaccharides are connected) Sucrose Maltose

25 Biological Molecules: Monosaccharides and Disaccharides Formation of a disaccharide

26 Biological Molecules: Carbohydrates: Complex Carbohydrates: (polymers with 3 or more sugars) Primarily used for energy storage or cellular structures Starch Glycogen Cellulose

27 Biological Molecules: Carbohydrates: Complex Carbohydrates: (polymers with 2 or more sugars)

28 Biological Molecules: Carbohydrates: Complex Carbohydrates: (polymers with 3 or more sugars) Starch Produced by plants Used to store energy (sugars) Rice, Potatoes and Grains

29 Biological Molecules: Carbohydrates: Complex Carbohydrates: (polymers with 3 or more sugars) Glycogen Produced by animals (animal starch) Used to store energy (sugars) Eventually broken down into simple sugars

30 Biological Molecules: Carbohydrates: Blood Sugar: Glucose, Glycogen and Insulin When blood glucose levels rise, and the pancreas secretes insulin. Insulin causes liver cells to build glycogen from glucose monomers When glucose levels fall, insulin secretion is reduced Glycogen synthesis stops. When energy is needed glycogen is broken down into glucose.

31 Biological Molecules: Carbohydrates: Complex Carbohydrates: (polymers with 3 or more monomers) Cellulose Produced by plants and other organisms Cellulose is primarily structural Most abundant carbohydrate on Earth Combined with Lignin, it can form cell walls in plants

32 Biological Molecules: Carbohydrates:

33 Life s Components: Biological Molecules 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

34 Biological Molecules: Lipids: Store Energy, used to make Hormones and Structures Non-polar (don t dissolve in Water) NOT made up of component monomers (like proteins, DNA, & carbos) Made up of Carbon, Hydrogen and Oxygen BUT have more hydrogen and less oxygen than carbohydrates Examples Fats, Oils, Cholesterol, Hormones

35 Biological Molecules: Lipids: Glyceride Lipids o Triglycerides Saturated and Unsaturated Fatty Acids o Phospholipids

36 Biological Molecules: Lipids: Glyceride Lipids Triglycerides Triglycerides are a type of fat (lipid) found in your blood. When you eat, your body converts some of the calories it doesn't need right away into triglycerides. The triglycerides are stored in your fat cells.

37 Biological Molecules: Lipids: Glyceride Lipids (what do they look like?) Made up of a Glycerol Head and Fatty Acid Tails May have from 1 to 3 Fatty Acid Tails hooked to hydroxyl (OH - ) groups Fatty Acid

38 Biological Molecules: Lipids: Glyceride Lipids Made up of a Glycerol Head and Fatty Acid Tails Triglyceride

39 Biological Molecules: Lipids: Glyceride Lipids Made up of a Glycerol Head and Fatty Acid Tails May have from 1 to 3 Fatty Acid Tails

40 Biological Molecules: Lipids: Glyceride Lipids Triglycerides Saturated and Unsaturated Fatty Acids

41 Biological Molecules: Lipids: Saturated and Unsaturated Fatty Acids Saturated Fatty Acids have no doublebonds between carbon atoms of the Fatty Acid Chain The Saturation is from the many Hydrogen atoms More Double Bonds, means fewer Hydrogen atoms Double bonds create kinks in the fatty acid Saturated fats have no kinks and pack tightly together at room temperature and tend to be solid

42 Biological Molecules: Lipids: Saturated and Unsaturated Fatty Acids Monounsaturated Fatty Acids have one double-bond between carbon atoms of the Fatty Acid Chain (Kinks)

43 Biological Molecules: Lipids: Saturated and Unsaturated Fatty Acids Polyunsaturated Fatty Acids have more than one double-bond between carbon atoms of the Fatty Acid Chain (Kinks) Mono and Polyunsaturated fatty acids have fewer hydrogen atoms so carbon atoms need to form double bonds to keep 4 chemical bonds

44 Biological Molecules: Lipids: Polyunsaturated Omega-3 Fatty Acids When a carbon double bond is located between the third and fourth carbons up from the omega (far) end, the result is an omega-3 fatty acid.

45 Biological Molecules: Lipids: Polyunsaturated Omega-3 Fatty Acids These raise HDL levels, guard against blood clot formation, reduce fat levels generally in the bloodstream, and reduce the growth of the fatty deposits that clog heart arteries. Omega-3 fatty acids are found most abundantly in certain kinds of fatty fish, including salmon, albacore tuna, mackerel, lake trout, and sardines; and in lesser amounts in plant-based foods such as canola oil, walnuts and the soybean-based product tofu.

46 Biological Molecules: Lipids: Saturated and Unsaturated Fatty Acids Glyceride Lipids and Fatty Acids Better for Cardiac Health Omega-3 Polyunsaturated Fats Polyunsaturated Fats Monounsaturated Fats Saturated Fats Trans Fats (hydrogenated fats) Worse for Cardiac Health

47 Biological Molecules: Lipids: Glyceride Lipids Triglycerides Saturated and Unsaturated Fatty Acids Phospholipids

48 Biological Molecules: Lipids: Phospholipids Have a Phosphate Head Have 2 Fatty Acid Chains Has a nonpolar fatty acid region (nonpolar) Has a (-) charged Phosphate group (makes the head polar) Phospholipids make excellent barriers (animal cell membrane)

49 Biological Molecules: Lipids: Phospholipids Have a Phosphate Head Have 2 Fatty Acid Chains

50 Biological Molecules: Lipids: Phospholipids Are an essential part of the cell membrane Polar heads orient towards the water inside and outside a cell

51 Biological Molecules: Lipids: Phospholipids Are an essential part of the cell membrane Polar heads orient towards the water inside and outside a cell They create a Phospholipid Bilayer when in water

52 Storage and Use of Carbohydrates and Lipids

53 Biological Molecules: Carbon s place in the living world 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

54 Biological Molecules: Monomers and Polymers Monosaccharaides, amino acids and nucleotides are all monomers that can exist in polymer chains.

55 Biological Molecules: Monomers and Polymers Monosaccharaides, amino acids and nucleotides are all monomers that can exist in polymer chains.

56 Biological Molecules: Proteins Amino Acid Monomers Chains of Amino Acids make up proteins There are 20 different Amino Acids Different arrangements of amino acids make different proteins

57 Biological Molecules: Proteins Amino Acid Monomers Chains of Amino Acids make up proteins There are 20 different Amino Acids Different arrangements of amino acids make different proteins

58 Biological Molecules: Proteins Amino Acid Monomers Chains of amino acids are called polypeptides. Proteins are polypeptides that fold up in a specific three dimensional manner that is biologically active

59 Biological Molecules: Proteins Amino Acid Monomers Chains of amino acids are called polypeptides. Proteins are polypeptides that fold up in a specific three dimensional manner that is biologically active

60 Three-Dimensional Shape in Molecules Molecular shape is very important! If the shape is changed at all, the molecule may lose its function Example: Hemoglobin Hydrogen Bonds also play a huge role in the final shape of molecules.

61 Biological Molecules: Proteins Proteins Made of chains of Amino Acid monomers (Polypeptides) Polypeptide Chains fold into Proteins Primary structure is determined by the sequence of Amino Acids Final structure is created by folding which is guided by the sequence of the Amino Acids in the chain. Examples: Enzymes, Structural Proteins

62 Biological Molecules: Types of Proteins Enzymes Hormones Transport proteins Contractile Protective Structural Storage Toxins Communication

63 Biological Molecules: DNA and RNA 3.1 Carbon's Place in the Living World 3.2 Functional Groups 3.3 Carbohydrates 3.4 Lipids 3.5 Proteins 3.6 Nucleic Acids

64 Biological Molecules: DNA 3.6 Nucleic Acids Deoxyribonucleic Acid (DNA) DNA is the primary information bearing molecule of life DNA is the CODE that determines which Amino Acids will be liked together during Protein Synthesis DNA generally forms Double Strands that are packaged in units called Chromosomes

65 Biological Molecules: DNA and RNA 3.6 Nucleic Acids Made up of monomer building-blocks called Nucleotides (4 different types) Nucleotide polymers form chains called DNA or RNA Humans have about 3 billion nucleotides in their DNA

66 Biological Molecules: DNA and RNA 3.6 Nucleic Acids Made up of monomer building-blocks called Nucleotides (4 different types) G, A, T, C The 4 nucleotides are identified by the first letter of their chemical names

67 Biological Molecules: DNA 3.6 Nucleic Acids DNA has two strands of Nucleotides The Strands are mirror images of each other, or complimentary Complimentary means that each nucleotide can only pair with one other nucleotide (A s pair w/ T s / G s pair w/ C s)

68 Biological Molecules: DNA 3.6 Nucleic Acids DNA has two strands of Nucleotides The Strands are mirror images of each other, or complimentary Complimentary means that each nucleotide can only pair with one other nucleotide (A s pair w/ T s / G s pair w/ C s)

69 Biological Molecules: Carbon s place in the living world 3.6 Nucleic Acids Ribonucleic Acid (RNA) RNA is involved in Protein Synthesis Also has 4 different nucleotides (very similar to DNA)

70 Biological Molecules: Carbon s place in the living world 3.6 Nucleic Acids Ribonucleic Acid (RNA) RNA is involved in Protein Synthesis Also has 4 different nucleotides (very similar to DNA)

71 Biological Molecules: Biological Molecules Summary