Nutrients of Life Unit 3

Key Questions 1. Why do organisms need/use nutrients? 2. What are organic vs. inorganic compounds? 3. What are some characteristics of certain nutrients? 4. What are enzymes and how do they function? 5. What factors affect the rate of enzyme action? 6. What reactions do nutrients undergo?

1. Why do Organisms Need Nutrients? 1. Energy 2. Growth 3. Repair 4. Chemical Reactions 5. Regulation

Why do Organisms Need Nutrients? Organisms must take in nutrients from the environment and change them into a form that they can use. There are different types of nutrients – organic and inorganic – both are found in cells and allow them to perform reactions to maintain life.

Remember the periodic table???

2. What are Organic vs. Inorganic Compounds? Inorganic compounds : Do not have BOTH carbon and hydrogen Examples: Water Acids (pH is 1-6) Bases (pH is 8-14) Salts Minerals (ex: calcium)

Remember pH?

Inorganic Nutrients a. Water Has many important functions to maintain internal balance Up to 60% of our bodies are water! How much water should you drink a day? Indicators – thirst, urine

Inorganic Nutrients b. Minerals Used in organisms to help perform certain functions. Examples: Calcium (bones) Iron (oxygen)

What are Organic vs. Inorganic Compounds? Organic compounds : Contain both carbon and hydrogen. Types: 1. Carbohydrates 2. Lipids 3. Proteins 4. Vitamins

Focus: Organic Compounds 1. Carbohydrates (Sugars) Examples Starch Glucose Cellulose Building Blocks Simple Sugars

Focus: Organic Compounds UsesEnergy ElementsC, H, O Chemical Indicators And Results -Starch – iodine (amber colored and turns blue/black) -Glucose – Benedict’s Solution (blue turns orange with heat)

Focus: Organic Compounds Iodine: amber-colored but turns blue/black in presence of starch Negative Positive

Focus: Organic Compounds Benedict’s Solution: Blue-colored and turns orange in the presence of glucose when heated

Focus: Organic Compounds The sugars we eat are very complex – they need to be broken down into simple sugars (like glucose) so that they can fit into our cells. Starch is a HUGE sugar, and glucose is a small sugar!

Focus: Organic Compounds 2. Lipids (fats) ExamplesFats, oils, waxes Building Blocks 3 fatty acids and 1 glycerol

Focus: Organic Compounds Uses Stored energy, insulation, cushioning ElementsC, H, O Chemical Indicators And Results Brown paper test for translucence

Biochemistry Glycerol 3 Fatty Acids

Biochemistry The cell membrane includes a lipid bilayer:

Biochemistry Examine a leaf!!! Why does it feel waxy???

Focus: OrganicCompounds 3. Proteins (polypeptides) Carry out most of the work in a cell. Make-up most things in your body (muscle, blood, hair, cells)

Focus: Organic Compounds Protein molecules are long, folded chains made of 20 different amino acids in a specific sequence. The order of the long chain of amino acids determines the SHAPE of the protein. The function of a protein depends on its shape

Focus: Organic Compounds

Proteins Examples Hormones, Enzymes, Antibodies Building Blocks Amino Acids

Focus: Organic Compounds Uses -Enzymes-Chemical Reactions ElementsC, H, O, N Chemical Indicators And Results Biuret’s Reagent – turns light purple with protein

Focus: Organic Compounds Biuret’s Reagent - turns light purple in the presence of protein.

Focus: Organic Compounds For Example: Enzymes are protein molecules that fit with a certain substrate. Hormones are protein molecules that fit with a certain membrane receptor.

Focus: Organic Compounds 4. Vitamins Organic compounds that your body needs in small amounts to function properly Get most from daily diet Examples: Vitamin D (bones) Vitamin C (immune)

How do Organisms Use Nutrients? Many of the complex nutrients we eat have to be broken down before they can be used to build new things. Enzymes help with these reactions of building and breaking down.

Enzymes Enzymes Enzymes are PROTEIN molecules Act as biological catalysts – affect the rate of chemical change without being changed themselves They are necessary for ALL chemical reactions to occur in cells! Have a specific shape that allows it to act on a specific molecule (substrate)

Enzymes Some enzymes help to build large molecules by joining substrates together Other enzymes help to break substrates apart

Enzymes Active Site: Where the enzymes join with the substrate.

Thought Question Why might enzyme action be referred to as the ‘Lock and Key Model’ for enzyme action?

Enzymes The shape of each active site of an enzyme only fits with certain substrates (just like a key for a door)

Enzyme Animations

Enzymes The rate at which enzymes work can be influenced by internal factors (inside your body) such as pH and temperature.

Enzymes 1. Temperature At high or low temperatures, enzymes may denature – enzyme changes shape, so it does not fit with the substrate The reaction may slow down or stop

Enzymes

Temperature and Enzyme Activity

Enzymes The optimum (best) temperature for enzymes depends on the organism! Enzymes found in humans work best at 98.6 degrees F Those found in dogs work best at 101 degrees F

Enzymes 2. pH The pH an enzyme works best in is different for each enzyme.

What are the optimal temperatures/p H for: Typical: human enzymes: Thermophilic bacteria: Pepsin: Trypsin:

Lactose Intolerance Lab

Question – Lactose Intolerance A lactose intolerant student fixed himself a cup of hot chocolate. He added the hot chocolate mix, milk, and lactaid and placed the mixture in the microwave for 2 minutes. He drank the hot chocolate while watching his favorite TV show and not soon after, he was running to the bathroom with awful cramps. He was so confused – what happened???

Lactose Intolerance Interesting fact! People with mild intolerance can usually have yogurt because the live cultures (bacteria!) break down much of the lactose into glucose and galactose – simple sugars that are easier to digest.

D. Reactions in Cells Chemical reactions are occur constantly in cells and they require enzymes! These reactions allow cells to build new molecules and break down others in order to maintain homeostasis. The major reactions are called synthesis and hydrolysis.

Reactions 1. Synthesis Building larger molecules from smaller ones with the use of enzymes When joining the pieces together, water is removed When small nutrients enter a cell, the cell will use them as building blocks in the synthesis of compounds necessary for life

Biochemistry

Reactions 2. Hydrolysis (Break Down) Breaking down larger molecules into smaller materials by adding water with the use of enzymes Occurs in digestion

Biochemistry

Biochemistry PRACTICE: Hydrolysis or Dehydration Synthesis?

Dehydration Synthesis or Hydrolysis?

Bill Nye – Nutrition (23 min.) Nye-Nutrition Nye-Nutrition

Applicable NYS Standards 1.2 h, 2.1 I, 5.1 c, 5.1 f, 5.1 g