E ssay 4. Classification s of Lipids: Based on chemical composition lipids are classified as follows: 1. Simple lipids or Homolipids: These are esters of fatty acids with various alcohols. A fat is solid at ordinary room temperature whereas oil is liquid. Compound lipids or Heteroliplds: These are esters of fatty acids with alcohol and having additional group s. Derived lipids: These are the substances derived from simple and compound lipids by hydrolysis.
These include fatty acids, alcohols, mono- and diglycerides, steroids, terpenes and carotenoids. They are the major components of storage or depot fats in plant and animal cells but are not normally found in membranes.
Most fats and oils, upon hydrolysis, yield several fatty acids as well as glycerol. Their generic formula is shown in the following figure: Obviously, when the groups attached to carbon 1 and 3 differ, a centre of asymmetry is created at C A fat molecule contains 3 moles of fatty acids, which may be similar or dissimilar.
Each performing their own unique function in the human body. Carbohydrates, or carbs, are used to spare the use of protein in the body and use it as energy.
Carbs can be found in many foods, such as grains, fruits and milk products Why is nutrition important. Nutrition, nourishment, or aliment, is the supply of materials - food - required by organisms and cells to stay alive. In science and human medicine, nutrition is the science or practice of consuming and utilizing foods MNT, A nutrient is a source of nourishment, an ingredient in a food, e.
Macronutrients are nutrients we need in relatively large quantities. Micronutrients are nutrients we need in relatively small quantities MNT, Eat Nutrition Guide for Adolescents Notes Nutrition education is often promoted among adolescents to prevent diabetes, obesity and induce healthier behavior change. Nutrition intervention programs are frequently reinforced by health educators or teachers to address the importance of healthier dietary practices among teenagers.
These interventions are often emphasized due to the nutritional vulnerability of this group. The Liver The liver is a vital organ in the body which does many things in order to keep the body functioning smoothly They take in nutrients and break them down to create energy molecules for the cell. They perform a process called cellular respiration, where they generate chemical energy in the form of adenosine triphosphate ADT from glucose sugar.
Mitochondria are small organelles that float around freely around the cell. These small capsule shaped cytoplasmic organelles are found in all eukaryotic animal and plant cells. Figure 1 shows the double membrane; the outer membrane is smooth and covers the organelle like a skin Carbohydrates, lipids, and proteins are the macronutrients.
Vitamins and minerals are classified as the micronutrient because they are only need in small doses Nutrition: Science and Applications, Carbohydrates, lipids, and proteins are energy yielding nutrients. A constant energy source for the body is carbohydrate nutrients.
Lipids are generally known as fats and oils. Lipids are also a source of energy stored in a lightweight form within the body Though the majority of people do not realize it yet, the possibility that gasoline could be replaced with biodiesel is very possible. The reason that biodiesel could become the next fuel is because with the state of industrialism today, carbon dioxide is being added to the atmosphere at alarming rates.
With about four hundred parts per million of carbon dioxide in the atmosphere today, complications are starting to occur, and will magnify as time goes on if we do not act CO2 Now In the absence of enzymes, most biological process might not occur.
The purpose of an enzyme is to allow the cell carry out its functions in time. As the structure of most biological molecules play a major role in their function, the three dimensional structure of an enzyme is responsible for its catalytic activities. Therefore, enzymes are proteins made of amino acids Prediction: The Prediction is that as the temperature rises as does the permeability of the cell membrane, as the permeability and the temperature increase so does the amount of pigment being released.
Introduction: During the experiment I worked with Helen Grinter. The Reasoning behind the experiment is to see what effects Temperature has on the permeability of Phospholipid bi-layer of Beetroot cells and the amount of pigment released from the vacuole Being an athletic-training major here at the University of Iowa, it is one of my many obligations to understand and be able to recall such properties very quickly.
By using mnemonic strategies, memory aid techniques that use vivid imagery and organization devices, I am able to defeat the challenge in my Organic Chemistry class of getting all the physical properties of lipids and proteins into my Long Term Memory and then recall them whenever I need In many animals, some lipids are secreted into external environment and act as pheromones that attract or repel other organisms.
They affect the texture and flavor of food and so its palatability. Food manufacturers use fat for its textural properties, e. Chefs know that fat addiction add to the palatability of meal and increase satiety after a meal.
Lipids are what help create all the living things we see everyday. Lipids are found in all membranes, mainly plasma membranes, meaning animals and plants contain lipids. In this paper I will display and explain the formation of micelles and bi-layers from lipid amphiphilicity. Contact: james. The sphingolipid is not a derivative of glycerol. The structure of the sphingosine is given below.
Once a fatty acid and a phosphate with an attached choline are bonded to the sphingosine, forming sphingomyelin Fig. The carbohydrates are most often glucose or galactose. Galactocerebroside is found almost exclusively in the membranes of brain cells. The general structure of cholesterol consists of two six-membered rings side-by-side and sharing one side in common, a third six-membered ring off the top corner of the right ring, and a five-membered ring attached to the right side of that.
Cholesterol is the central steroid from which other steroids such as the sex hormones are synthesized. Cerebrosides are important constituents of the membranes of nerve and brain cells.
The sphingolipids called gangliosides A sphingolipid that contains a fatty acid unit, a sphingosine unit, and a complex oligosaccharide. Because of considerable variation in their sugar components, about varieties of gangliosides have been identified.
Most cell-to-cell recognition and communication processes e. Gangliosides are most prevalent in the outer membranes of nerve cells, although they also occur in smaller quantities in the outer membranes of most other cells. Because cerebrosides and gangliosides contain sugar groups, they are also classified as glycolipids. However, certain charged and polar species do cross the membrane, aided by proteins that move about in the lipid bilayer.
The two major classes of proteins in the cell membrane are integral proteins A protein that spans the lipids bilayer of membranes. Peripheral proteins may be attached to integral proteins, to the polar head groups of phospholipids, or to both by hydrogen bonding and electrostatic forces. Small ions and molecules soluble in water enter and leave the cell by way of channels through the integral proteins. Some proteins, called carrier proteins, facilitate the passage of certain molecules, such as hormones and neurotransmitters, by specific interactions between the protein and the molecule being transported.
Concept Review Exercises Name the structural unit that must be present for a molecule to be classified as a phospholipid. Why is it important that membrane lipids have dual character—part of the molecule is hydrophilic and part of the molecule is hydrophobic?
Why do you suppose lecithins phosphatidylcholines are often added to processed foods such as hot cocoa mix? Answers a saccharide unit monosaccharide or more complex sphingosine The dual character is critical for the formation of the lipid bilayer.
The hydrophilic portions of the molecule are in contact with the aqueous environment of the cell, while the hydrophobic portion of the lipids is in the interior of the bilayer and provides a barrier to the passive diffusion of most molecules.
Lecithin acts as an emulsifying agent that aids in the mixing of the hot cocoa mix with water and keeps the cocoa mix evenly distributed after stirring. Key Takeaways Lipids are important components of biological membranes. These lipids have dual characteristics: part of the molecule is hydrophilic, and part of the molecule is hydrophobic. Proteins are another important component of biological membranes.
Integral proteins span the lipid bilayer, while peripheral proteins are more loosely associated with the surface of the membrane. Some lipids can be given more than one classification. Draw the structure of the sphingomyelin that has lauric acid as its fatty acid and ethanolamine as its amino alcohol.
Draw the structure of the cerebroside that has myristic acid as its fatty acid and galactose as its sugar. Distinguish between an integral protein and a peripheral protein.
What is one key function of integral proteins? Answers phospholipid sphingolipid and glycolipid Integral proteins span the lipid bilayer, while peripheral proteins associate with the surfaces of the lipid bilayer.
All the lipids discussed so far are saponifiable, reacting with aqueous alkali to yield simpler components, such as glycerol, fatty acids, amino alcohols, and sugars. For more information about saponification, see Section Lipid samples extracted from cellular material, however, also contain a small but important fraction that does not react with alkali. The most important nonsaponifiable lipids are the steroids A lipid with a four-fused-ring structure..
These compounds include the bile salts, cholesterol and related compounds, and certain hormones such as cortisone and the sex hormones.
Steroids occur in plants, animals, yeasts, and molds but not in bacteria. They may exist in free form or combined with fatty acids or carbohydrates. All steroids have a characteristic structural component consisting of four fused rings. Chemists identify the rings by capital letters and number the carbon atoms as shown in part a of Figure
The sphingolipids called gangliosides A sphingolipid that contains a fatty acid unit, a sphingosine unit, and a complex oligosaccharide. It is of two types — a Dipalmitoyl lecithin, b Lysolecithin.
Concept Review Exercises Name the structural unit that must be present for a molecule to be classified as a phospholipid. Draw the structure of the sphingomyelin that has lauric acid as its fatty acid and ethanolamine as its amino alcohol. Gangliosides are most prevalent in the outer membranes of nerve cells, although they also occur in smaller quantities in the outer membranes of most other cells. They serve primarily as structural components of membranes and are never stored in large quantities. Soft soaps, made with potassium salts, are more expensive but produce a finer lather and are more soluble.
There are several classes of lipids — fatty acids, triacylglycerols, phospholipids, glycolipids, and steroids. The project experiment involved growing algae in water which was placed under a carbon dioxide tank. These have also been identified from soybean oil. Classification s. Why is it important that membrane lipids have dual character—part of the molecule is hydrophilic and part of the molecule is hydrophobic? These are not found in significant quantities in plant tissues.