Biology · Chemistry

Lipids, Fats, and Biochemistry

1,009 Questions

Lipids, fats, and biochemistry explore the structure and function of biological molecules. This includes fatty acids, cholesterol, trans-fats, and cellular membranes. Questions on this topic frequently appear in science sections of competitive government exams.

Types of fats and lipidsCholesterol and human bodyFatty acidsCellular membranes

Lipids, Fats, and Biochemistry Questions

Multiple choice

In humans, the largest energy reserve is

  1. liver glycogen

  2. muscle glycogen

  3. blood glucose

  4. adipose tissue triacylglycerol
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

While glycogen stored in the liver and muscles provides short-term energy reserves, adipose tissue stores large amounts of triacylglycerols (fats), which serve by far as the largest and most abundant long-term energy reserve in the human body.

Multiple choice

Which of the following statements is NOT TRUE in case of oxidative rancidity of fatty foods?

  1. Peroxides and hydroperoxides are formed during auto-oxidation.

  2. Auto-oxidation is a complex chain reaction.

  3. The final breakdown products of auto-oxidation are aldehydes, ketones and alcohols.

  4. The reaction is brought about by an enzyme, called lipase.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Oxidative rancidity is a non-enzymatic auto-oxidation process involving free radicals, oxygen, and unsaturated fatty acids, rather than a reaction catalyzed by the enzyme lipase.

Multiple choice

What is the relationship of this graph?

  1. As time increases, lipid mass increases

  2. As time increases, lipid mass decreases

  3. As time decreases, lipid mass decreases

  4. As time decreases, lipid mass increases
Reveal answer Fill a bubble to check yourself
B Correct answer
Multiple choice biology coordination in life processes ingestion of food mechanism of digestion

What are called micelles during absorption

  1. Small glycerol molecules

  2. Small droplets of fatty acids

  3. Very small fat droplets

  4. Large fat molecules
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Micelles are small spherical aggregates formed by bile salts and fatty acids/monoglycerides, which facilitate the transport of lipids to the intestinal absorptive cells.

Multiple choice senescence senescence and death plant growth plant growth and development biology

The fluidity of membranes in a plant in cold weather may be maintained by?

  1. Increasing the number of phospholipids with unsaturated hydrocarbon tails

  2. Increasing the proportion of integral proteins

  3. Increasing concentration of cholesterol in membrane

  4. Increasing the number of phospholipids with saturated hydrocarbon tail
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In cold weather, membranes tend to solidify. Increasing the proportion of unsaturated phospholipids (which have kinks in their tails) prevents tight packing, thereby maintaining fluidity.

Multiple choice biology caskets of life the cell structure cytoplasm unicellular and multicellular organisms number and shape of cells

Select the correct option:

Lipids are arranged within the membrane with

  1. Polar heads toward inner side and the hydrophobic tails toward outerside

  2. Both heads and tails toward outerside

  3. Heads toward outerside and tail towards inside

  4. Both heads and tails toward innerside
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In lipid bilayer, lipids are arranged with the polar head towards the outer side and the hydrophobic/ non-polar tails towards the inner side.

Multiple choice biology meaning of life chemical organization in living beings lipids proteins and their structure

The other name of fats is

  1. Lipids

  2. Proteins

  3. Carbohydrates

  4. Nucleic acids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Proteins are the polymers of amino acids held together by peptide bonds and are also called as polypeptides. Carbohydrates (sugars) are polyhydroxy aldehyde or ketones or their derivatives. Nucleic acids are polymers of nucleotides held together by phosphodiester bonds. Fats are fatty acid derivatives and are one of the storage lipids. Thus, the correct answer is A.

Multiple choice biology meaning of life chemical organization in living beings lipids proteins and their structure

Most essential fatty acid is ..........

  1. Linoleic acid

  2. Oleic acid

  3. Arachidonic acid

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The most essential fatty acids are that fatty acids that are not synthesized in our body and must come from the food we eat. For example, Linoleic acid (Omega-6 fatty acid ) is a most essential fatty acid. Linolenic acid is found in vegetable oils such as sunflower, soybean, corn, and canola oils as well as nuts and seeds.
So, the correct answer is 'Linoleic acid'.
Multiple choice biology meaning of life chemical organization in living beings lipids proteins and their structure

Lipids are insoluble in water because they are

  1. Neutral

  2. Zwitter ions

  3. Hydrophobic

  4. Hydrophilic
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Lipids are hydrophobic means water hating. They are water insoluble. Lipids are non-polar molecules while water is polar molecule, so there is no way for water to attach to a lipid molecule. Instead, the non-polar lipids will bind to themselves, which is why oils and fats form droplets on the surface of water.