Transcript Lipids PPT

Intro to Organic
Molecules
& Lipids
AP Biology
Life is based on Carbon
 Carbon atoms are versatile
building blocks
 Special bonding properties
 Has 4 valence electrons so it can form
4 stable covalent bonds with other carbon atoms or atoms of other
elements
 Bonds with
CHNOPS – the elements that make up living things;
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur
H
H
C
H
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H
Lipids
 Lipids are organic molecules essential for life that are
composed mostly of C, H, O
 4 types of lipids
 fats (triglycerides)
 phospholipids
 steroids
 waxes
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Triglycerides
 Fat molecules
 Structure = 3 fatty acids chains linked to glycerol
 Functions = long term energy storage and insulation for animals
 Can be saturated or unsaturated
Glycerol
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3 fatty
acids
Saturated fats
 All C bonded to H
 No C=C double bonds
 long, straight chain
 most animal fats and butter
 solid at room temperature
 contributes to
cardiovascular disease
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Unsaturated fats
 At least one C=C double bond in
the fatty acids
 plant & fish fats
 vegetable oils
 liquid at room temperature
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Saturated vs. unsaturated
saturated
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unsaturated
Phospholipids
 Structure: 2 fatty acids chains + phosphate head
 Fatty acid chains = non-polar = hydrophobic “water fearing”
 Phosphate head = polar = hydrophillic “water loving”
 Function: make up cell membranes
(phospholipid bilayer)
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Steroids
 Structure: 4 fused Carbon rings
 examples:
 cholesterol – Function =control the fluidity of the cell membrane
 hormones – Function = regulate processes in the body (such as pregnancy)
 vitamins (A, B, D) – Function = supports metabolism and cell processes
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Waxes
 Solid at room temp
 Insoluble in water
 Function:
 Protective covering for
animals and plants
 Examples:



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Beeswax
Earwax
Cuticle of leaf (keeps water in)
What is the function of a
triglyceride?
1. Stores and transfers
genetic information
2. Long term energy
storage
3. Control the rate of
reactions
4. Help to fight disease
75%
15%
10%
0%
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1
2
3
4
Which type of lipid makes up the
majority of the cell membrane?
1. phospholipids
79%
2. waxes
3. steroids
4. triglycerides
11%
5%
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1
2
5%
3
4
Fats that have at least one double
bond between Carbon atoms are
called
1. Unsaturated
65%
2. Saturated
3. Glycerol
4. Fatty Acids
20%
5%
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1
2
3
10%
4
Phospholipids have a
1. hydrophobic head and
hydrophilic tail
2. hydrophilic head and
hydrophobic tail
84%
16%
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1
2
Which of the following is an
example of a steroid
1. Fatty acids
88%
2. Sex hormones
3. Phospholipids
4. Olive Oil
12%
0%
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1
2
3
0%
4