Fatty acids are key building blocksThe longer the chain, the more solid the fat.
lipid composition
Of what are saturated fats composed?
usually animal fats
straight and stack solid
How are Monounsaturated Fats composed?
One double bond
found in olive oil
tend to bend, can't stack as well
How are polyunsaturated fats composed?
Many double bonds, more liquid
greater than one double bond, lower melting point ex: margarinebutter has higher melting point
stack tightly and form solids at room temp
fatty acids
How do short chain fatty acids form at room temp?
Liquid form at room temp
T/FMonounsaturated oils store in adipose tissue?
False. Monounsaturated do not store in adipose tissue
What are some sources of saturated fatty acids?
Bacon, meats, animal fats
What are some sources of monounsaturated fats?
olive oil, avocado, canola and peanut oils
What are some sources of polyunsaturated fats?
safflower, sunflower, corn oil, soy
What happens to polyunsaturated fats if left out?
When double bonds are present, these fats are easier to spoil, attract O2 and becomes rancid easily
Some double bonds take on a H+ atom. A single bond develops and straightens the fatty acid chain. Not all double bonds will attach to Hydrogen. Some fatty chains will keep double bonds and twist to form a trans shape and not Cis.
process of hydrogenation
Which is better, Cis formed fatty acid chains or Trans formed fatty acid chains? Why?
Cis is the better form of fatty acid chains. Fatty acid chain maintains same shape as is natural with double bond between two central carbons and added Hydrogen on bottom side of each Carbon. This causes a V shape which makes them difficult to stack. The Trans form is a straighter chain and these can stack easily
What is the structure of a triglyceride?
Glycerol + 3 fatty acids.
Name some functions of triglycerides.
Energy source and reserveInsulation and protectionCarrier of fat-soluble vitsSensory qualities in food
How much of dietary fat is in the form of triglycerides?
95%
What do we get from fat?
Energy. Fat will give ATP.
What are the two essential fatty-acids?
Linoleic acid
Alpha-linolenic acid
Why are essential fatty acids considered essential?
Because the human body does not make them, so the human body must get them by consuming the fatty acids
What is omega-3 fatty acid made of?
Linolenic + EPA, DHA
What is omega-6 fatty acid made of?
Linolenic + arachidonic + GMA
What are good sources of Omega-3 and Omega-6?
Salmon, sardines, blue fish, herring, tuna
What fish should humans eat less of?
Tilapia and catfish: make omega-6 and increase risk of heart disease, stroke, inflammation of arteries
What are the beneficial properties of cod liver oil?
Rich in omega-3 fats
decrease NSAIDS if patient requires for arthritis pain
What is the structure of phospholipids?
Glycerol + 2 fatty acids + phosphate group
How much of dietary fat is phospholipids?
2% of dietary fat
For what are sterols precursors?
sterol hormones, Vitamin D, bile acids.
What are food sources of sterols?
found only in animal foods
How much dietary fat comes from sterols?
3% of dietary fat
What happens to fats in the mouth?stomach?small intestine?
in the mouth, fats melt
stomach- gastric lipase breaks up fat
SI- main hydrolysis of FA
emulsified by phospholipids and bile
digested by pancreatic lipase
fat micelles transport to SI walls
absorbed into intestinal cells
(formed into chylomicrons and moved into lymphatic system via lacteals)
Deliver dietary lipids from intestines to cells and liver
chylomicron
deliver triglycerides to cells
VLDL
deliver cholesterol to cells
LDL
How many Kcal per gram of fat?Is fat a good energy source?
9 Kcal/gm
Yes
How much resting energy comes from fat?
60% of resting energy is from fat
How does fat function for storage?
a gram of fat stores more than 6x as much energy as a gram of glycogen.
A micronutrient carrier
fat
What does fat carry?
fat-soluble vits and carotenoids
What determines the traits of amino acids?
the side group determines the traits
How many total AA needed to build a protein?
20 AA
How many essential AAs?
9 essential AA
What makes AAs essential?
Conditionally essential amino acids become essential if not able to convert essential to non-essential
What will be formed if 2 AA are joined?if 3 AA?
dipeptide
tripeptide
How are AA joined?
peptide bonds
denaturation: to uncoil the proteinchange the shape of the protein
protein breakdown
Where does hydrolysis of proteins begin? What happens there?
Hydrolysis starts in the stomach. There, HCl- uncoils and activates pepsin
_________ is the breakdown of AAs. immediate fate of excess protein. NH3- transformed to urea, store glycogen, fat if excess
Deamination
What happens if protein levels are too low?
No protein for cell wall, water leaks in, cells swell, resulting edema
What is an example of a transport protein?
lipoprotein
What are the functions of proteins?
electrolyte balance transport protein
transport proteins
structure- collagen matrix
maintenance of pH levels
immune system function
makes hormones
makes blood
makes ferritin to help heal wounds
What is the only source of Nitrogen for the body?
proteins
What is done with carbon skeleton from protein deamination?
use AAs to make glucose, ketones or fat
What will happen to excess proteins?
excess proteins will make fat
What is the RDA for protein?
0.8g/kg/day
What is Kwashiokor?
an acute lack of protein
What is Marasmus?
a chronic condition of too little protein
In what are vegan diets lacking?
low in B12, omega-3, iron, and zinc
The sum of all chemical reactions in the body's cells.
metabolism
What is the function of ribosomes?
protein synthesis
What is the most metabolically active organ in the body?
liver
what does the liver do?
metabolizes, stores and distributes nutrients after absorption
____allow chemical reactions to occur at fast enough rates for normal body function
enzyme
During fasting or starvation, _____ are catalyzed to glucagon during times of starvation.__________ when under stress
triglycerides
Epinephrine or cortisol
_______ are the backup fuel for the brain and nerve function when glucose is limited
ketone
_______ are the backup fuel for the brain and nerve function when glucose is limited
ketone
what happent to excess carbs?
Excess carbs are stored as glycogen in the liver and muscles
what happens to excess carbs and protein
Excess carbs and proteins are converted to triglyceride through lippgenesis and stored as adipose tissue (FAT)
