Carbohydrates and Lipids

Honors Biology

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The sugar starch and in your fiber soda and the in your bread , fruit and vegetables are all carbohydrates .

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You consume more carbohydrates than any other organic biomolecule .

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A carbohydrate is an organic macromolecule.

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QUESTION: Do you remember what ORGANIC means???

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QUESTION: Do you remember a synonym for “macromolecule?”

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Carbohydrates are composed of carbon, hydrogen and oxygen in a 1:2:1 ratio.

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Short-term energy storage

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Fiber

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In Animals In Plants

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Energy storage

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Structure of Cell Wall

Carbohydrate Formula:

C 6 H 12 O 6

Notice the ratio of 1:2:1 for carbon, hydrogen and oxygen atoms.

C 2 H 4 O 2 CH 4 O 2 C 3 H 4 O 5 C 6 H 12 O 6 C 3 H 6 O 3 C 36 H 72 O 36

Notice the ratio of 1:2:1?

For every

two one

carbon there are hydrogens and

one

oxygen!

1.

2.

3.

Short-term energy storage in animals (glycogen) Used to create energy (glucose) in all organisms Plant cell walls (cellulose) and plant energy storage (starch) What is dietary fiber?

Parts of a plant that we eat but cannot digest. Fiber acts like a broom in our gut, cleaning out decaying food particles.

Celery, popcorn, and whole wheat are high in fiber

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All carbohydrates can be categorized by size

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Three main sizes of carbohydrates — Mono saccharides (“ one sugar”) Di saccharides (“ two sugars”) Poly saccharides (“ many sugars”)

Building block of all carbohydrates

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It is also called a single or simple sugar .

Glucose

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Six-sided, diamond-like shape

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Polysaccharides hundreds or are composed of thousands of monosaccharide molecules bound together .

Glucose is the primary energy source for most organisms .

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Energy is stored of the glucose in the molecule.

chemical bonds

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The energy respiration is released during cellular in organisms .

Thousands starches of glucose molecules found in the make up the foods you eat .

“two sugars”

Sucrose Sugar Glucose

+

Fructose

Monosaccharides

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Polysaccharides are made of long chains of glucose molecules.

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Glycogen and starch are broken down into glucose molecules during digestion

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The glucose molecules then go to your cells where they are broken down to release energy during cellular respiration.

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Glucose molecules are created by plants during photosynthesis. The glucose molecules are bound together in long chains to make starch.

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Starch, a polysaccharide, is stored in plants until the plant needs to use it. When you eat starchy foods, like potatoes, you break the starch down into glucose.

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Your body will bind glucose molecules together to make glycogen. Glycogen, a polysaccharide, is stored in your muscles and liver for later use by you!

Grains Starch Energy storage in plants!

Carbs stored in muscles Glycogen Energy storage in you!

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Ever wonder why plants have stiff and rigid stems and leaves? Every plant cell is surrounded by a rigid cell wall made of cellulose.

Cellulose is a tough polysaccharide that most organisms cannot digest. The chemical bonds in cellulose make it hard to digest.

Cellulose Structure in plant cell walls!

1.

What is the C:H:O ratio found in all carbohydrates?

2.

True or false: Glycogen is used to store energy in plants.

3.

True or false: Starch is a source of dietary fiber 4.

True or false: Glucose is a disaccharide 5.

True or false: Polysaccharides are composed of two monosaccharides bound together

 Nonpolar, organic molecules  Composed of hydrogen (C), and oxygen (O) (H), carbon  Lipids consist of two types of molecules glycerol & fatty acids

 Glycerol - an alcohol - Serves as backbone of the molecule

 3 Fatty acids Long hydrocarbon chains

 All lipids are insoluble in water  Lipids are a more efficient energy storage system carbohydrates – become FAT STORAGE

Energy stored in bonds of lipids – fats store 2.5

than

times as much energy per unit as carbs

 Major component of cell membrane

Cell membrane = Phospholipid bilayer

Phospholipids have a hydrophyllic end and a hydrophobic end

“Hydrophobic” – water fearing “Hydrophillic” – water loving

These ends give the membrane many of its properties!!!

1.

Would it be more efficient to store energy as glycogen or as fat? Why???

2.

Why are lipids considered an organic molecule?

3.

What does it mean to be hydrophobic?

4.

What is the name of the lipid that makes up the cell membrane?

  Saturated fats have long chains with no double-bonds Unsaturated fats have double bonds between hydrogen and carbon

Triglycerides:  composed of 3 molecules of fatty acids and 1 molecule of glycerol

 Oils lipids that are liquid at room temperature  Fats lipids that are solid at room temperature

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Waxes

– lipid that gives many substances a waterproofing cover Examples: surface of plant leaves, ear wax 

Steroids

– lipids that cause changes within an organism Examples: nerve tissue,plant poisons, hormones, and venoms