Docsity
Docsity
Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity

Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan

Guidelines and tips
Guidelines and tips
Sell on Docsity
Sell on Docsity
Docsity AI
Docsity AI
Log inSign up

Prepare for your exams

Study with the several resources on Docsity

Find documents

Prepare for your exams with the study notes shared by other students like you on Docsity

Search for your university

Find the specific documents for your university's exams

Docsity AINEW

Summarize your documents, ask them questions, convert them into quizzes and concept maps

Explore questions

Clear up your doubts by reading the answers to questions asked by your fellow students

Earn points to download

Earn points by helping other students or get them with a premium plan

Share documents
download point icon20 Points

For each uploaded document

Answer questions
download point icon5 Points

For each given answer (max 1 per day)

All the ways to get free points
Get points immediately

Choose a premium plan with all the points you need

Study Opportunities

Choose your next study program

Get in touch with the best universities in the world. Search through thousands of universities and official partners

Community

Ask the community

Ask the community for help and clear up your study doubts

Free resources

Our save-the-student-ebooks!

Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors

Lipids - clarification,functions, Study notes of Biochemistry

University of CalicutBiochemistry

Lipids Classification Structure Functions

Typology: Study notes

2022/2023

Uploaded on 03/04/2023

sophie-yasbella
sophie-yasbella 🇮🇳

1 document

1 / 3

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Lipids definition
• Lipids are a heterogeneous group of organic compounds that are
insoluble in water and soluble in non-polar organic solvents.
•They naturally occur in most plants, animals, microorganisms and
are used as cell membrane components, energy storage molecules,
insulation, and hormones.
Properties of Lipids
Lipids may be either liquids or non-crystalline solids at room
temperature.
Pure fats and oils are colorless, odorless, and tasteless.
They are energy-rich organic molecules
Insoluble in water
Soluble in organic solvents like alcohol, chloroform, acetone,
benzene, etc.
No ionic charges
Solid triglycerols (Fats) have high proportions of saturated fatty
acids.
Liquid triglycerols (Oils) have high proportions of unsaturated
fatty acids.
Structure of Lipids
Lipids are made of the
elements(Carbon,(Hydrogen(and(Oxygen, but have a much
lower proportion of water than other molecules such
as(carbohydrates.(
Unlike polysaccharides and proteins, lipids are not polymers—
they lack a repeating monomeric unit.
They are made from two molecules:(GlycerolandFatty
Acids.
A glycerol molecule is made up of three carbon atoms with a
hydroxyl group attached to it and hydrogen atoms occupying
the remaining positions.
Fatty acids consist of an(acid group(at one end of the molecule
and a hydrocarbon chain, which is usually denoted by the
letter ‘R’.
They may be(saturatedorunsaturated.
A fatty acid is saturated if every possible bond is made with a
Hydrogen atom, such that there exist no C=C bonds.
pf3

Partial preview of the text

Download Lipids - clarification,functions and more Study notes Biochemistry in PDF only on Docsity!

Lipids definition

  • Lipids are a heterogeneous group of organic compounds that are insoluble in water and soluble in non-polar organic solvents. •They naturally occur in most plants, animals, microorganisms and are used as cell membrane components, energy storage molecules, insulation, and hormones.

Properties of Lipids

 Lipids may be either liquids or non-crystalline solids at room temperature.  Pure fats and oils are colorless, odorless, and tasteless.  They are energy-rich organic molecules  Insoluble in water  Soluble in organic solvents like alcohol, chloroform, acetone, benzene, etc.  No ionic charges  Solid triglycerols (Fats) have high proportions of saturated fatty acids.  Liquid triglycerols (Oils) have high proportions of unsaturated fatty acids.

Structure of Lipids

 Lipids are made of the elements Carbon, Hydrogen and Oxygen, but have a much lower proportion of water than other molecules such as carbohydrates.  Unlike polysaccharides and proteins, lipids are not polymers— they lack a repeating monomeric unit.  They are made from two molecules: Glycerol and Fatty Acids.  A glycerol molecule is made up of three carbon atoms with a hydroxyl group attached to it and hydrogen atoms occupying the remaining positions.  Fatty acids consist of an acid group at one end of the molecule and a hydrocarbon chain, which is usually denoted by the letter ‘R’.  They may be saturated or unsaturated.  A fatty acid is saturated if every possible bond is made with a Hydrogen atom, such that there exist no C=C bonds.

 Unsaturated fatty acids, on the other hand, do contain C=C bonds. Monounsaturated fatty acids have one C=C bond, and polyunsaturated have more than one C=C bond

Classification (Types) of Lipids

Lipids can be classified according to their hydrolysis products and according to similarities in their molecular structures. Three major subclasses are recognized:

1. Simple lipids

(a) Fats and oils which yield fatty acids and glycerol upon hydrolysis. (b) Waxes , which yield fatty acids and long-chain alcohols upon hydrolysis Fats and Oils  Both types of compounds are called triacylglycerols because they are esters composed of three fatty acids joined to glycerol, trihydroxy alcohol.  The difference is on the basis of their physical states at room temperature. It is customary to call a lipid a fat if it is solid at 25°C, and oil if it is a liquid at the same temperature.  These differences in melting points reflect differences in the degree of unsaturation of the constituent fatty acids. Waxes  Wax is an ester of long-chain alcohol (usually mono-hydroxy) and a fatty acid.  The acids and alcohols normally found in waxes have chains of the order of 12-34 carbon atoms in length.

2. Compound lipids

(a) Phospholipids , which yield fatty acids, glycerol, amino alcohol sphingosine, phosphoric acid and nitrogen-containing alcohol upon hydrolysis. They may be glycerophospholipids or sphingophospholipid depending upon the alcohol group present (glycerol or sphingosine). (b) Glycolipids , which yield fatty acids, sphingosine or glycerol, and a carbohydrate upon hydrolysis. They may also be glyceroglycolipids or sphingoglycolipid depending upon the alcohol group present (glycerol or sphingosine).