FIRST FIVE• True or false? If false, correct to make true

1. Monomers are made of many polymers

2. Hydrolysis reactions produce water

3. Glycogen is a polysaccharide

4. Cellulose is the main source of energy for humans

5. Starch is a disaccharide

6. Amylose chains in starch have a branched structure.

• CELL STRUCTURE UNIT EXAM• CORRECTIONS DUE NO LATER THAN, THURSDAY, FEBRUARY 27

• QUIZ: CARBOHYDRATES & LIPIDS• FRIDAY, FEBRUARY 28 [GOLD 1]

TODAY’S ANNOUNCEMENTS

LIPIDS

WHAT IS FAT?

HTTP://ED.TED.COM/LESSONS/WHAT-IS-FAT-GEORGE-ZAIDAN

WHY DON'T WATER AND OIL MIX?

HTTP://ED.TED.COM/LESSONS/WHY-DON-T-OIL-AND-WATER-MIX-JOHN-POLLARD

WHAT DO EAR WAX, HORMONES, CHOLESTEROL, AND WHALE BLUBBER ALL HAVE IN COMMON?

WHY DO WE NEED FAT? WHAT BIOLOGICAL PURPOSES DO YOU THINK IT SERVES?

WHAT SUBSTANCES CONTAIN LIPIDS?

LIPIDS• Lipids molecules include

• triglycerides (fats and oils)• waxes• steroids

• Lipids are non-polar• lipids do not dissolve in water

• Phospholipids make up all cell membranes.

MAIN FUNCTIONS OF LIPIDS

1. Long term energy storage

2. Protection against heat loss (insulation)

3. Protection against physical shock

4. Protection against water loss

5. Chemical messengers (hormones)

6. Major component of membranes (phospholipids)

MAIN FUNCTIONS OF LIPIDS

1. LONG TERM ENERGY STORAGE

2. PROTECTION AGAINST HEAT LOSS (INSULATION)

3. PROTECTION AGAINST PHYSICAL SHOCK

4. PROTECTION AGAINST WATER LOSS

5. CHEMICAL MESSENGERS (HORMONES)

6. MAJOR COMPONENT OF MEMBRANES (PHOSPHOLIPIDS)

TRIGLYCERIDES• Composed of 1 glycerol unit and 3 fatty acids

• Commonly called “fats” and “oils”

FATTY ACID STRUCTURESATURATED FATTY ACIDS

• No carbon double bonds

• Typically solids at room temperature

• More common in animals

UNSATURATED FATTY ACIDS

• Have a double bond somewhere between the carbons

• Have less hydrogen than a saturated fatty acid

• Melt more easily

• Typically liquids at room temperature

• More common in plants

(A)SATURATED OR (B)UNSATURATED?

(A)SATURATED OR (B)UNSATURATED?

SATURATED VS. UNSATURATED: SIMILAR BUT DIFFERENT

SATURATED VS. UNSATURATED FATS

WHAT TYPE OF REACTION DO YOU THINK ATTACHES THE FATTY ACIDS ONTO

GLYCEROL?

Glycerol + 3 Fatty Acids Triglyceride + 3 Water

TRIGLYCERIDE MODELS

• FOLLOW THE INSTRUCTIONS ON THE HANDOUT TO MAKE MODELS SHOWING 2D- TRIGLYCERIDE SHAPE

PHOSPHOLIPIDS • Phospholipids make up all cell

membranes and play a large role in determining what gets in and out of the cell.

• Hydrophilic and hydrophobic regions give phospholipids their unique properties.

Hydrophilic – “water loving”

Hydrophobic – “water hating"

STRUCTURE OF PHOSPHOLIPIDS• 2 FATTY ACIDS+1

PHOSPHATE GROUP• ONE END IS SOLUBLE

IN WATER (PHOSPHATE GROUP)

Hydrophobic

Hydrophilic

STRUCTURE OF PHOSPHOLIPIDS• IDENTIFY THE FOLLOWING:

• GLYCEROL• SATURATED FATTY ACID• UNSATURATED FATTY

ACID• PHOSPHATE GROUP

PRACTICE WITH VOCAB: FRAYER MODELS• IN YOUR NOTEBOOK, CREATE A FRAYER MODEL FOR THE FOLLOWING TOPICS:

LIPIDS, TRIGLYCERIDES, AND PHOSPHOLIPIDS

Definition: Characteristics:

Drawing of structure: Example:(Write topic here)

PRACTICE

• BEGIN LIPIDS PRACTICE PROBLEMS

• COMPLETE AS HOMEWORK. DUE THURSDAY.

EXIT TICKET: HOW DOES THE STRUCTURE OF A LIPID RELATE TO ITS FUNCTION?

WRITE 2-3 SENTENCES.