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The structure of oleic acid is shown. This fatty acid has a hydrocarbon chain seventeen residues long attached to an acetyl group. The bond between carbon eight and carbon nine is a double bond.
Oleic acid is a common unsaturated fatty acid.

Most unsaturated fats are liquid at room temperature and are called oils. If there is one double bond in the molecule, then it is known as a monounsaturated fat (e.g., olive oil), and if there is more than one double bond, then it is known as a polyunsaturated fat (e.g., canola oil).

When a fatty acid has no double bonds, it is known as a saturated fatty acid because no more hydrogen may be added to the carbon atoms of the chain. A fat may contain similar or different fatty acids attached to glycerol. Long straight fatty acids with single bonds tend to get packed tightly and are solid at room temperature. Animal fats with stearic acid and palmitic acid (common in meat) and the fat with butyric acid (common in butter) are examples of saturated fats. Mammals store fats in specialized cells called adipocytes, where globules of fat occupy most of the cell’s volume. In plants, fat or oil is stored in many seeds and is used as a source of energy during seedling development. Unsaturated fats or oils are usually of plant origin and contain cis unsaturated fatty acids. Cis and trans indicate the configuration of the molecule around the double bond. If hydrogens are present in the same plane, it is referred to as a cis fat; if the hydrogen atoms are on two different planes, it is referred to as a trans fat    . The cis double bond causes a bend or a “kink” that prevents the fatty acids from packing tightly, keeping them liquid at room temperature ( [link] ). Olive oil, corn oil, canola oil, and cod liver oil are examples of unsaturated fats. Unsaturated fats help to lower blood cholesterol levels whereas saturated fats contribute to plaque formation in the arteries.

A comparison of saturated and unsaturated fatty acids is shown. Stearic acid, a saturated fatty acid, has a hydrocarbon chain seventeen residues long attached to an acetyl group. Oleic acid also has a seventeen-residue hydrocarbon chain, but a double bond exists between the eighth and ninth carbon in the chain. In cis oleic acid, the hydrogens are on the same side of the double bond. In trans oleic acid, they are on opposite sides.
Saturated fatty acids have hydrocarbon chains connected by single bonds only. Unsaturated fatty acids have one or more double bonds. Each double bond may be in a cis or trans configuration. In the cis configuration, both hydrogens are on the same side of the hydrocarbon chain. In the trans configuration, the hydrogens are on opposite sides. A cis double bond causes a kink in the chain.

Trans fats

In the food industry, oils are artificially hydrogenated to make them semi-solid and of a consistency desirable for many processed food products. Simply speaking, hydrogen gas is bubbled through oils to solidify them. During this hydrogenation process, double bonds of the cis - conformation in the hydrocarbon chain may be converted to double bonds in the trans- conformation.

Margarine, some types of peanut butter, and shortening are examples of artificially hydrogenated trans fats. Recent studies have shown that an increase in trans fats in the human diet may lead to an increase in levels of low-density lipoproteins (LDL), or “bad” cholesterol, which in turn may lead to plaque deposition in the arteries, resulting in heart disease. Many fast food restaurants have recently banned the use of trans fats, and food labels are required to display the trans fat content.

Omega fatty acids

Essential fatty acids are fatty acids required but not synthesized by the human body. Consequently, they have to be supplemented through ingestion via the diet. Omega -3 fatty acids (like that shown in [link] ) fall into this category and are one of only two known for humans (the other being omega-6 fatty acid). These are polyunsaturated fatty acids and are called omega-3 because the third carbon from the end of the hydrocarbon chain is connected to its neighboring carbon by a double bond.

Questions & Answers

explain cell biology
Grace Reply
what are endotherms
angelina Reply
pls can someone elaborate more on biomagnification
angelina
Hey,what?
Peter
Biomagnification, also known as bioamplification or biological magnification, is any concentration of a toxin, such as pesticides, in the tissues of tolerant organisms at successively higher levels in a food chain.
chance
An endotherm (from Greek ἔνδον endon "within" and θέρμη thermē "heat") is an organism that maintains its body at a metabolically favorable temperature, largely by the use of heat set free by its internal bodily functions instead of relying almost purely on ambient heat.
chance
What diffusion
Oseres Reply
it is the movement of water molecules from the region of higher concentretion to a region of lower concentration
Lukas
is the movement of anything from region of higher concentration to a region of lower concentration.
chance
pls I don't know how to read very well so how can I understand all this
Mercy Reply
What's succession
Talabi Reply
an acid is a substance that produces hydrogen ions in an aqueous solution
angelina Reply
what is acid
asaa Reply
An acid is a substance which gives Hydrogen ions in aqueous solutions.
Ahsan
food poison
asaa
the difference between prokaryotic cells and Eukaryotic cells
Itz Reply
karyon is nucles eukaryotes have intact membrane around its nucleus, whereas prokaryotes don't have nuclear membrane and other membrane bounded organelles
Ishitha
what is the function of chyme
Divine Reply
what makes a tissue
Divine
cells
Yazi
tell me
Betty
chyme where digested food passes from e stomach through e pyloric sphincter in 2 e duodenum.
Mary
what is an osmosis
SSEJJO Reply
tell me the answer
Betty
Osmosis is the movement of the water molecules through a semipermiable membrane from lower to higher concentrated solution.
Ahsan
is the movement of water molecules from the area of high concentration to the area of low concentration through a semi permeable membrane.
SSEJJO
what is hypertonic solution
SSEJJO
A solution having more solute concentration as compared to a cell which is in place, results shrinkage of cell.
Ahsan
what is water potential
SSEJJO
uses of Osmosis
SSEJJO
what is the meaning of hypothesis
Memory Reply
what is the function of chyme
Jack Reply
what is meiosis,and does it work
Chisom Reply
it's a reduction of chromosomes it is caried by haploid in which it divides the chromosomes by 2 this means by 23n -23n
Mwansa
what is biology
WESINA Reply
is a branch of science that deals with the environment
Ali
The term biology is a combination of two things I .e bio mean life and logy mean study ; And all the study is about life .
Bangura
biology is a branch of science which deal with the study of living organisms and their vital processes .
Sky
biology is the branch of science that deal with the combination of living things and non living things i.e plant and animal
Ezenwa
what is genetic
Mumbere Reply
what is reproduction
Mumbere

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Source:  OpenStax, Biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11448/1.10
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