Lipids are essential constituents of the diet because of their _________.

Lipids consist of fats, oils, hormones, and certain components of membranes that are grouped together because of their hydrophobic interactions.

Which of the following are essential for the fat-soluble vitamins and the essential fatty acids found with the fat of the natural foodstuffs?

Fats combined with proteins (lipoproteins) are essential constituents of the ________ and ________ of the cell.

Lipids occur naturally in living beings like plants, animals, and microorganisms that form various components like ________, hormones, and energy storage molecules.

Lipids may be either ______ or non-crystalline solids at room temperature.

Which of the following statements about pure fats and oils is correct?

Lipids are energy-rich organic molecules.

Are lipids soluble in water?

Lipids are soluble in which of the following?

Solid triglycerides (Fats) have high proportions of ______ fatty acids.

Liquid triglycerides (Oils) have high proportions of ______ fatty acids.

What is the process called when triglycerols react with water to form their carboxylic acid and alcohol?

Saponification is the process where triacylglycerols are hydrolyzed by alkali to produce soap.

The carbon-carbon double bonds in unsaturated fatty acids can be hydrogenated to produce ______ fatty acids.

What is the term applied to any fat or oil that develops a disagreeable odor due to hydrolysis and oxidation reactions?

Lipids are made of which elements?

Unlike polysaccharides and proteins, lipids are not ________.

Lipids are made from two molecules: ________ and ________.

A fatty acid is saturated if every possible bond is made with a ________ atom, such that there exist no C=C bonds.

Which of the following statements is true about unsaturated fatty acids?

Monounsaturated fatty acids have how many C=C bonds?

Polyunsaturated fatty acids have more than one C=C bond.

What are simple lipids?

Fats and oils are both called ________ because they are esters composed of three fatty acids joined to glycerol, trihydroxy alcohol.

What is the main difference between fats and oils at room temperature? Choose the correct answer:

The differences in melting points between fats and oils reflect differences in the degree of ________ of the constituent fatty acids.

What is a wax? Choose the correct answer:

The acids and alcohols normally found in waxes have chains of the order of ________ carbon atoms in length.

What are compound lipids?

Phospholipids may be classified as ________ or ________ depending upon the alcohol group present.

Glycolipids may also be ________ or ________ depending upon the alcohol group present (glycerol or sphingosine).

Hydrolysis products of simple and compound lipids are called derived lipids. Which of the following are included in derived lipids?

Steroid derivatives are phenanthrene structures that are quite different from lipids made up of _________.

Which molecule contains a carbon atom double-bonded to an oxygen atom and single-bonded to another oxygen atom?

The most important and frequently occurring alcohol found in lipids is _________.

Glycerol is a small organic molecule consisting of three hydroxyls (OH-) groups.

Fats and oils are esters of fatty acids and ________, whereas waxes are esters of fatty acids and long-chain alcohols.

The esters of fatty acids are formed after the ________ reaction between the fatty acids and the alcohol molecules.

What are triglycerides?

Triglycerides are the main constituents of body fat in humans, other vertebrates, and _________.

What are triglycerides composed of?

In naturally occurring triglycerides, the fatty acid chains mostly contain how many carbon atoms?

True or False: The three fatty acids involved in the condensation reaction are usually identical, and their chain length is the same.

Even-numbered carbon atoms present in animals and plants indicate the pathway of their biosynthesis from ________.

Simple triglycerides might also have identical fatty acids forming ________.

Why are triglycerides insoluble in water?

Functions of Triglycerides: Triglycerides are important macromolecules as they store most of the ______ in the body.

Where are triglycerides stored before being released into the bloodstream?

Functions of Triglycerides: The fat stored in the body forms a layer of ______ beneath the skin, which helps to maintain the body temperature.

Functions of Triglycerides: Triglycerides also aid in the absorption and transport of ______-soluble vitamins in the body.

What are Fatty acids? Fatty acids are organic molecules that are long-chained carboxylic acids with ______ carbon atoms.

What are Fatty acids? The hydrocarbon chains in fatty acids are either ______ or unsaturated, depending on the bonds between the carbon atoms.

If all carbon-carbon bonds are single, the acid is ________.

If one or more carbon-carbon double bonds are present, the acid is:

Naturally occurring fatty acids are mostly:

Fatty acids are stored as an energy reserve (fat) through an ester linkage to ________ to form triglycerides.

Which type of fatty acid has only single carbon-carbon bonds?

What are the simplest form of fats that are unbranched linear chains of CH2 groups linked together by carbon-carbon single bonds with a terminal carboxylic acid?

The term 'saturated' is used to indicate that the maximum number of hydrogen atoms are bonded to each carbon atom in a molecule of fat.

What is the general formula for saturated fatty acids?

Fatty acids obtained from an animal source are mostly even-numbered linear chains of saturated fatty acids.

Saturated fatty acids usually have a higher melting point than their counterparts.

Saturated fatty acids are mostly solid and are found in animal fat like butter, meat, and whole milk. But some saturated fatty acids are also found in vegetable sources like vegetable oil, coconut oil, and peanut oil.

Unsaturated fatty acids are more complex fatty acids with bent hydrocarbon chains linked together by one or more carbon-carbon double bonds with a terminal carboxylic acids group.

The term 'unsaturated' indicates that the carbon atoms do not have the maximum possible hydrogen atoms bound to carbon atoms.

Due to the presence of double bonds, the cis and trans conformation of unsaturated fatty acids are important. The unsaturated fatty acids found in the human body exist in the ______ conformation.

Unsaturated fatty acids have a lower melting point as compared to saturated fatty acids, and thus they exist in the liquid state at room temperatures.

Most vegetable oils and fish oils are some of the important sources of ______ fatty acids.

Glycerol is a simple organic compound with how many hydroxyl groups?

What is the process called in which ester bonds are formed between glycerol and fatty acids?

Which of the following statements is TRUE about glycerol?

The lipid molecules formed from three fatty acids and a single glycerol molecule are termed as ________.

The process of condensation in the formation of ester bonds is termed esterification.

A phospholipid is an organic molecule consisting of fatty acids, a phosphate group, and a ________ group that forms the main component of various cellular membranes. Fill in the blank.

Which part of the cell membrane is primarily responsible for the selective transport of molecules in and out of the cell?

The phosphate group forms the ________ head, whereas the fatty acids form the ________ tails in phospholipids. Fill in the blanks.

True or False: The head and tail regions in phospholipids are joined by a glycerol molecule.

What enables the passage of biomolecules through the lipid bilayer of the cell membrane?

The hydrophilic head of the phospholipid contains a negatively charged ________ group with an unidentified alkyl group. Fill in the blank.

The hydrophilic region of a phospholipid might or might not be polar or charged.

As water is a polar molecule, the hydrophilic head of the phospholipid immediately forms ________ interaction with the water molecule.

Refer to the diagram of phospholipids. Which part of the phospholipid is hydrophobic?

The hydrophobic part of the phospholipid bilayer is also termed the water-fearing portion that consists of long non-polar fatty acid tails.

Fill in the blank: The hydrophobic tails of phospholipids are tucked towards the _______ of the membrane to shield them from water.

Which of the following statements is true about hydrophobic tails in the phospholipid bilayer?

The main function of hydrophobic interactions in the phospholipid bilayer is to:

Sterols are a type of lipids composed of steroid alcohols occurring naturally in which of the following?

What is the most important and familiar type of sterol that plays an essential role in cell membrane structure and functions?

Cholesterol acts as a precursor to fat-soluble vitamins like Vitamin D and hormones.

Cholesterol is formed of how many linked hydrocarbon rings forming the bulk of the steroid structure?

The hydroxyl group in cholesterol joins with which of the following?

In humans, which organ makes up 100% of all cholesterol required for the body?

Cholesterol is considered essential for the regulation of membrane fluidity in animals.

What does cholesterol increase in the cell membrane?

Fill in the blank: Biological lipids are a chemically diverse group of compounds, and the biological functions of the lipids are as diverse as their ________.

In the body, fats serve as an efficient source of energy and are also stored in the ________ tissues. These also serve as an insulating material in the subcutaneous tissues and around certain organs.

Which of the following are major structural elements of biological membranes?