The lipids: Triglycerides, Phospholipids and Sterols

organic, sterols

The Lipids
- Organic (contain carbon) compounds soluble in _________- solvents but not in water
- contains triglycerides, phospholipids, _______

Triglycerides, 3, lipid, diet

- glycerol + ___ fatty acids
- fat= triglycerides, the major form of ______ found in food and in the body
- tissues can assemble or disassemble triglycerides
- Usually include mixtures of various fatty acids
- Fats in the ________ influence composition of fats in the body with their fatty acids

pictures to study

- slide 5 (2 lunches)
- slide 16 (essential PUFA)
- slide 18- fish oil stuff
- slide 21 (what is good fat)

saturated, unsaturated

Saturated vs Unsaturated Fatty Acids
- Can differ in chain length but also degree of saturation
- A _______(1)______ fat is a triglyceride that contains 3 _____(1)_____ fatty acids, an ____(2)_______ fat has 1 or more ______(2)______ fatty acids

point of unsaturation

a site of the chain that has a double bond between 2 carbons, with a lack of some hydrogen atoms

saturated fatty acids

have no points of insaturation

unsaturated fatty acid

have one or more points of insaturation.
- monosaturated
- polysaturated

monosaturated fatty acids (MUFA)

only 1 point of insaturation,

polyunsaturated fatty acids (PUFA)

have 2
or more points of insaturation

Degree of Saturation, animal, tropical

- Degree affects the melting temp of fats, their softness or hardness
- Most vegetable and fish oils are rich in PUFA, MUFA, while __________ fats are generally saturated, _________ oils have also been shown to elevate blood cholesterol

phospholipids, 2, lecithin, double, signals

- Molecule of glycogen with ____ fatty acids and contains phosphorus= soluble in water
- Emulsifier
- Emulsification is used by food manufacturers to blend fats with watery ingredients. The phospholipid ___________ (in egg yolks) blends the vinegar with the oil forming the mayonnaise
- Phospholipids bind together in a strong _________ layer that forms the membranes of the cells. They help fats travel back and forth across the lipid membranes and can generate __________ inside the cells in response to hormones

Sterols, membranes, plaques, plants

- Interconnected rings
- Cholesterol serves as a raw material for making emulsifiers in bile, vitamin D and some sex hormones, also important in cell _________
- Cholesterol forms major part of ____________ that narrow arteries (underlying cause of heart attacks and strokes)
- Exists in _______

stomach, small intestine, monoglycerides

Digestion and Absorption of Fats
- Starts in mouth with enzyme
- _________--- fats separate
- _________ ___________- after emulsification fat-splitting enzymes cleave triglycerides into free fatty acids, glycerol and __________________(a glycerol molecule with one fatty acid)

short chain, lipid, least, bloodstream,

Transport of Fats
- Glycerol and _________ ________ fatty acids enter straight into the bloodstream
- The cells of intestinal lining convert large ______ fragments, such as monoglycerides and long chain fatty acids, back to triglycerides and combine them with protein forming the chylomicrones (a type of lipoprotein that has the ________ density) that travel in the lymph vessels to the __________ (and so to the liver and other tissues). This is a trick to carry lipids in the watery blood

Very low density lipoproteins (VLDL)

They carry triglycerides and other lipids made
in the liver to the body cells for their use

Low density lipoproteins (LDL)

They carry cholesterol and other lipids to the tissues. They are made from VLDL after they have donated many triglycerides to cells

High density lipoproteins (HDL)

They carry cholesterol away from body cells to the liver for disposal

HDL (good cholesterol)

carries excess cholesterol in your blood back to your liver where it's broken down and removed from your body. This means a high level of this cholesterol can maintain your heart health.
- smaller, denser and with more proteins
- best way to raise is physical activity

LDL (bad cholesterol)

carries cholesterol to your cells. But when you have too much, it can build up in your artery walls, causing them to narrow. This reduces blood flow, which can be bad for your heart health.
- larger, lighter and reacher in cholesterol

food, carbs, triglycerides

Storing and using the Fat
- Stores fat serves when ______ is unavailable
- Fat deposits
- Body can store excess ________ as fat
- When tissues need energy fat cells dismantle _____________ releasing fatty acids into the blood. The energy-hungry cells break them further into small fragments, which combine with fragments from glucose and the energy-releasing process continues liberating energy, carbon dioxide, and water

fat deposits

fat layer under the skin, the internal fat pad of the abdomen, the breasts, etc.

arachidonic, fish

Essential PUFA
- Starting from dietary linoleic acids, the body can produce other members of the omega-6 family. One of the _______________ acid.
- Two family members of great interest are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), made from linolenic acid in the tissues of __________

solid, smoking point, shapes, trans

- Hydrogenation of unsaturated fatty acids makes fat more ________ and resistant to the chemical change of oxidation or breakdown from high temperature
- Hydrogenated oil has a high _____________ ________ (the temperature at which fat gives of an acrid blue gas), so it is suitable for frying foods at high temperature
- During hydrogenation some points of unsaturation change their _________ instead of becoming saturated. This creates TRANS unsaturated fatty acids that are similar to saturated fats in shape and their effects on health
- Keep _______ fats as low as possible

hidden, 4, 95, skin

Food Sources of Fatty acids (1)
- Pay attention to the ________ solid fats, which supply the majority of the solid fats in the U.S. diet
- Meat can contain different amounts of fat. To be called "lean" it must contain fewer than 10g of fat, __g of saturated fat and ____mg of cholesterol per 100g of food. A lean cut is named round
- Chicken and turkey flesh are naturally lean but their ________ should be removed