Big Idea 2: BIOLOGICAL SYSTEMS UTILIZE FREE ENERGY and MOLECULAR s1

Name ______Date ______Period _____ Lipids Raven Ch. 3 Big Idea 2: BIOLOGICAL SYSTEMS UTILIZE FREE ENERGY AND MOLECULAR BUILDING BLOCKS TO GROW, TO REPRODUCE AND TO MAINTAIN HOMEOSTASIS.

Essential Knowledge:  All living systems require constant input of free energy.  Organisms capture and store free energy for use in biological processes.  Organisms must exchange matter with the environment to grow, reproduce and maintain organization.  Organisms exhibit complex properties due to interactions between their constituent parts.  Interactions between molecules affect their structure and function.  Variation in molecular units provides cells with a wider range of functions.

Lipids

Lipids are composed of ______ long ______chains (H-C)

Lipid “Family groups” . ______. ______. ______. ______. Do not form ______ Lipids are-______made of smaller subunits  not a repeating chain

Fats and Oils . Structure:

 ______+ ______

. fatty acid = long ______“tail” with ______(COOH) group “head”

1 . Triacylglycerol (______)  3 ______linked to ______ ______linkage = between ______& ______

How do the 3 fatty acids link to the glycerol? ______

Fats store energy . Long Hydrocarbon chain  polar or non-polar?  hydrophilic or hydrophobic?

. Function:  ______. concentrated . all C-C; C-H bonds! . 2x more than carbs  ______ ______. Think whale blubber

Saturated fats . All ______are bonded to maximum number of ______. No ______ long, straight chain  most ______fats  ______at room temp. . contributes to cardiovascular disease (atherosclerosis) = plaque deposits

2 Unsaturated fats . ______in the fatty acids  ______& ______fats  ______oils  ______at room temperature . the ______made by double bonded Carbons prevent the molecules from packing tightly together . Monounsaturated- ______. Polyunsaturated- ______. (Partially) Hydrogenated-? ______

Phospholipids . Structure:  ______+ 2 ______+ ______

. PO4 = ______charged

Hydrophobic or hydrophilic? . fatty acid tails = ______

. PO4 head = ______. Split “personality”

Phospholipids in water

. Hydrophilic heads “______” to H2O

. Hydrophobic tails “______” from H2O  can self-assemble into “bubbles”  bubble = “______”  can also form a ______ Early evolutionary stage of cell? bilayer 3 . Phospholipids create a barrier in water  define outside vs. inside  they make ______!

Soap? ______

Steroids . Structure:  4 ______+ ?? . different steroids created by attaching different ______to rings . different structure creates different ______Examples: ______

cholesterol

Cholesterol . Important cell component  animal cell ______ ______of all other steroids . including vertebrate ______ high levels in blood may contribute to ______disease . helps keep cell membranes ______4 From Cholesterol  Sex Hormones

. What a big difference a few atoms can make!