Lipids Flashcards
What are the four types of lipids?
simple lipids
compound lipids
derived lipids
sterols
T/F LIpids are hydrophobic
True
What are the two types of trycliccerides?
fats and oil
What are the main difference between fat and oil
Fat is solid at room temperature and oil is liquid at room temperature
Saturated fats are all _____ bonds while unsaturated fats have a one or more _____ bond
single, double
Phospholipids have a _____ head and a ______ tail
hydrophilic, hydrophobic
Phospholipids make up the___________
cellular membrane
_____ is a universal solvent
alcohol
Lipids are components of ______ and ______ tissue
plant, animal
What is the most abundant steroid present in animal tissue?
cholesterol
What is cholesterol a precursor to?
vitamin D, bile acids, and steroid hormones
Fat yields the most kilocalories, at _ calories per gram.
9
Where are chylomicrons formed?
the endoplasmic reticulum
What is the function of chylomicrons?
To transport dietary lipids to adipose, skeletal, and muscle tissue from the digestive tract since the blood is water and fats are hydrophobic
T/F There is a dietary requirement for lipids
False, All of the energy in a diet can be provided by CHOs although there is a requirement for Essential Fatty Acids due to their role as a solvent in fat-soluble vitamin absorption
What are the fat soluble vitamins?
A,D,E,K
What is the function of Vitamin A?
antioxidant, coloring
What is the function of Vitamin D?
made with sunlight, deficiency causes rickets, regulates Ca:P ratio
What is the function of Vitamin E?
antioxidant, role in preventing stroke, cancer, and heart disease
What is the function of Vitamin K?
contributes to blood clotting factors
What vitamin deficiency causes Night Blindness?
Vitamin A
What are symptoms of Night Blindness?
faulty night vision, rough hair coat, severe scours, stunted growth
What vitamin deficiency causes Osteomalacia (rickets)?
Vitamin D and an incorrect ratio of calcium to phosphorus
What are the symptoms of Osteomalacia?
lack of appetite, weight loss, enlarged or stiff joints, bowed legs
What vitamin deficiency causes Stiff-Lamb Disease (White Muscle Disease)?
Vitamin E/selenium
How do you prevent Stiff Lamb Disease?
Vitamin E/Selenium injections at docking time and 2-4 weeks of age
Symptoms of vitamin K deficiency:
easy bruising, oozing from nose or gums, excessive bleeding from wounds, puncture wounds, and injection of surgical sites, heavy menstrual periods, bleeding from gi tract, and blood in urine/stool
What are the functions of lipids?
energy reserves, structure of cell membranes, organ padding, body thermal insulation, essential fatty acids, hormone synthesis, and fat-soluble vitamin absorption
The double bond of unsaturated fatty acids forms _____ which do not allow for a solid and organized structure
kinks
What is the first step of the digestion of lipids?
emulsification
What is emulsification?
the dispersion of lipids in small droplets
What is the combination of bile salts, fatty acids, monoglycerides, and other fat-soluble substances called?
micelles
What are lipids emulsified by?
bile salts/bile acids
How do bile salts/acids emulsify lipids?
they function as a detergent and break down large lipid molecules to form smaller lipid droplets surrounded by a layer of bile
What are emulsified lipids acted upon by?
enzyme pancreatic lipipasease
What do emulsified lipids turn into?
fatty acids, monoglycerides, and glycerol
T/F: micelles are water soluble
True
T/F: bile salts are recycled and return to the intestine to continue emulsifying
True
T/F: micelle components are absorbed by the small intestine through active transpoty
false, passive transport
_____ and _______ are temporary compounds formed during lipid absorbtion
micelles and chylomicrons
The lipid digestion products are transported to the _______ surface for absorption.
small animal
Fatty acids and glycerol can be turned into….
ATP through oxidation or triglycerides
Fatty acids undergo ______ oxidation to form _______ in the _________ and enters the _________
beta; acetyl-CoA; mitochondria; krebs cycle
What are simple lipids?
esters of fatty acids with various alcohols
ex. wax, fat, oil
What are compound lipids?
esters of fatty acids containing nonlipid substances like phosphorous, carbs, and proteins in addition to alcohol and fatty acids
ex. phospholipids, glycolipids, and lipoproteins
What are derived lipids?
substances derived from simple or compound lipids by hydrolysis
ex. fatty acids, glycerol, and other alcohols
What are sterols?
(steroids) xflipids with complex phenanthrene-type ring structures
ex. cholesterol
phospholipids
compound lipid containing phosphoric acid and N
glycolipids
compound lipid containing carbohydrate and N
lipoprotein
compound lipid bound to proteins in blood and other tissue
______ acid and ________ acid cannot be synthesized by animal tissue, so they must be supplied in the diet
linoleic and linolenic
Where are chylomicrons secreted into after fats are assembled into them?
the lymphatic system
what is lipemia?
high amount of lipids in the blood
pancreatic lipase breaks down triglycerides into ______ and ________
free fatty acids, monoglycerides
what can free fatty acids be used for?
stored or used for energy
What affects major composiiton and concentration of lipids in the blood?ti
the type and quantity of lipids, the time after a meal, species, age, and endocrine status
What tissue stores triglycerides most notably?
adipose tissues
How can adipose tissue be created?
CHOs and oxidation of fatty acids
How do you lose weight?
fasting so that energy intake is less than current needs and there is a net loss of triglycerides
The fatty acid composition of the depot fat of nonruminants is represented by their _____
diet
What is biohydrogenation?
the process of turning unsaturated fatty acids into trans fats in the rumen since microbes do not like unsaturated fats, makes fats less toxic
a cows diet should be ___% fat
3-4
How does diet affect rumen performance?
Too much fat and the biohydrogenation process will be overwhelmed, fats will not become saturated and the rumen microbes will die
What are the main lipoproteins?
chylomicrons, VLDL, LDL, and HDL
these classifications are based on density and composition
what does VDLD do?
what does LDL do?
what does HDL do?
- delivers triacylglycerols from the liver to the extrahepatic tissues
- carries most cholesterol to tissues
- offloads remaining cholesterol and triglycerides to the liver to be marked for excretion
chylomicrons are synthesized in the _____ _______
VLDL, LDL, and HDL are synthesized in the ______ and ______
small intestine; small intestine, liver
What are the three major sites of biosynthesis of fatty acids and triglycerides?
liver, mammary gland, adipose tissue
lipogenesis
- synthesizing lipids as a means of storing chemical energy
- long term energy depot
- encompasses fatty acid synthesis, adipocyte uptake, and storage of lipids as the body’s ‘saving account’
______ it the key signal for fat storage
glucose
As ____ accumulates and insulin concentrations increase, the enzyme acetyl CoA carboxylase is stimulated
ATP
saturated fats are _____, unsaturated fats are _____
solid; liquid
an increase in saturation or a decrease in double bonds leads to stacking which is a more _____ fat
solid
an increase in unsaturation makes fats more ______ and ______ the melting point
liquid, decreases
In mice and rats, _____ of synthesis occurs in the liver
In chickens and pigeons, _____ of synthesis occurs in the liver
In pigs, _______ of synthesis occurs in adipose tissue
In cows and sheep, ________ predominates although both are important
half
nearly all
nearly all
adipose
________ occurs when there is low incoming glucose due to starvation, so the liver has to make ketone bodies to serve as an alternate energy source
ketogenesis
what are lipid soluble hormones?
steroids, thyroid hormones, retinoic acid, and nitric oxide
sings of EFA deficiencies:
Dermatitis in nonruminants such as scaly skin and tail necrosis, growth failure, reproductive failure, edema, subcutaneous hemorrhage, poor feather in chicks
Carnivore diets under _% total fat can induce fatty acid deficiencies
5
EFAs should be ___% of the diet
5-15
T/F: Cecal fermenters and ruminants are prone to EFA deficiency
false, microbes synthesize adequate amounts of fat
______ tend to have more saturated fat than _____ and the body fat composition of _____ is less responsive to the diet due to rumen microbes
ruminants;nonruminants;ruminants
fatty liver is the accumulation of lipids in the liver could be due to a number of reasons like
high-fat or high-cholesterol diet, increased liver lipogenesis caused by excessive CHO or intake of certain B vitamins, cellular damage to the liver because of infections, vitamin e-selenium deficiency, liver poisons like chloroform, mushrooms, and sago palms
atherosclerosis
cholesterol deposits in arteries, seen mostly in humans and pigs
