Biology Lesson9.1

Lesson 9.1 Nutrition/Digestions

2 reasons we need to intake and digest food:

Need structural materials

Need Energy for life processes

Structural needs:

•Need to rebuild cells, etc. that are breaking down

Types of materials needed:

•97% body is composed of carbon, hydrogen, oxygen, and nitrogen

•3% composed of calcium, phosphorus, iron, magnesium, sulfur and chlorine

Energy needs:

•Oxidation = is the process where a substance is combined with oxygen•Food you eat is oxidized and broken down into smaller units•Then energy is released•Energy is captured in a molecule known as ATP

ATP:

•ATP = adenosine triphosphate

•Has 3 phosphate groups

•When energy is needed one phosphate bond is broken and energy that can be used by cell is released.

ATP continued:

•Results in ATP becoming ADP.

•ADP can be recycled to ATP again by adding a phosphate group.

Molecules important to your body:

Molecules important to your body:

1. Carbohydrates:

•60% daily caloric intake

•Main source of energy for ATP

•Molecules are 1:2:1 C:H:0 example glucose is C6H12O6

Carbohydrates continued:

•Includes:•Simple sugars•Starches – long chains of simple

sugars•Glycogen – animal starch•Cellulose – plants use in cell

wall; good source of dietary fiber

Carbohydrates continued:

Eat whole grains as a source of carbs to get vitamins, minerals, and nutrients that your body needs

Molecules important to your body:1. Carbohydrates:

2. Proteins:Building blocks of the cell and its partsMade of smaller units called amino acids22 different amino acids that make up all proteins

Proteins continued:

Composed of Amino acidsAmino acid structure:R = functionalgroup that changes fromamino acid to amino acid making them different; rest same

Proteins continued:

•Should be 10% of daily caloric intake•Found in lean meats, milk, cheese, eggs, soybeans, legumes•Best if eaten in three meals•Need essential amino acids = ones the body can’t make & U must get from diet

Phenylalanine, valine, threonine, tryptophan, isoleucine, methionine,

histidine, leucine, and lysine

Nine essential amino acidsFYI DON’T NEED TO COPY!

Copy - Basically:when you eat your

protein food source your body breaks the protein down into amino acids and then uses them to rebuild things

Molecules important to your body:1. Carbohydrates:2. Proteins:

3. LIPIDS (FATS, OILS)Should be less than 25% of daily caloric intake

Should avoid saturated and hydrogenated oils

Lipids continued:

Why we need:Stored energy source

Used for building materials especially cell membraneTransport fat soluble vitaminsMake up some hormones like cholesterol

Types of lipids:Fatty acids – most basic type, carbon chain with Hydrogen

Types of lipids:Fatty acids – most basic type, carbon chain with H

Triglycerides – larger molecules three fatty acids with one glycerol

Lipids continued:

Saturated vs. UnsaturatedSaturated fats have more hydrogen atoms attached than unsaturated fats.Saturated are solid at Room TempEx. ButterUnsaturated are liquid at Room Temp ex. canola oil - are healthier

Lipids continued:

Hydrogenation – process of adding hydrogen atoms to an unsaturated fat to saturate it ex. margarine

Extra fat in the body is stored in adipose cells under the skin and around body organs.

Lipids continued:

Lipoproteins – transfer fats in the body3 categories of lipoproteins:1. Very low density (VLDLS)2. Low density (LDL’s) high in

cholesterol (bad)3. High density (HDL’s) high in

proteins (good)