Biology · Chemistry

Lipids, Fats, and Biochemistry

1,130 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 bio-chemistry biological molecule lipids and their function some biomolecules lipids

Which of the following statements concerning unsaturated fats is correct?

  1. They have fewer fatty acid molecules per fat molecule

  2. They have double bonds in the carbon chains of their fatty acids

  3. They generally solidify at room temperature

  4. They contain more hydrogen than do saturated fats having the same number of carbon atoms
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When one or more double bonds are present between the carbon chains of the fatty acids it is known as unsaturated fats. They have a large number of fatty acid molecules per fat molecule. Due to the presence of double bonds they contain a lesser number of hydrogen bonds as compared to the saturated fatty acid molecules.

Hence, the correct answer is 'They have double bonds in the carbon chains of their fatty acids'

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Select the correct option:

Which of the following is a saturated fatty acid?

  1. Oleic acid

  2. Linoleic acid

  3. Arachidonic acid

  4. Palmitic acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fatty acids are two main types- saturated and unsaturated fatty acids are without double bonds in their carbon chains. They have higher melting points and are solids at room temperature. They have a general formula of $C _nH _{2n}O _2$,e.g., $C _{16}H _{32}O _2$ (palmitic acid), $C _{18}H _{36}O _2$ (stearic acid).

Animal fats are mostly saturated fats.
Unsaturated fatty acids contain one or more double bonds in their carbon chains. They have lower meting points and are liquids at room temperature. Their general formula is $C _nH _{2n-2x} O _2$,e.g., oleic acid (with one double bond, monoene, $C _{18}H _{34}O _2)$, linoleic acid (with two double bonds, diene,$C _{18}H _{32}O _2$),linolenic acid (with three double bonds,triene, $C _{18}H _{30}O _2$).arachidonic acid (with four double bonds,tetraene,$C _{20}H _{32}O _2$).Plant fats are generally unsaturated fats.
So, the  correct answer is 'Palmitic acid'.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Which among the following is not a common saturated fatty acids encountered in nature?

  1. Butyric acid

  2. Palmitoleic

  3. Acetic and palmitic

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fatty acids are carboxylic acids with hydrocarbon chains of 4 to 36 carbons. In some fatty acids, this chain is fully saturated (meaning it cannot accept any more hydrogens) and unbranched; other fatty acids contain one or more double bonds (thus, they can be hydrogenated when the double bonds will get converted into single bonds).

Common examples of saturated fatty acids are butyric acid having four carbon atoms, lauric acid having twelve carbon atoms, myristic acid having fourteen carbon atoms, palmitic acid having sixteen carbon atoms, etc. Common unsaturated fatty acids are palmitoleic acid having sixteen carbon atoms and one double bond, oleic acid having eighteen carbon atoms and one double bond, linolenic acid having eighteen carbon atoms and two double bonds, etc.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Which one of the following is not an essential fatty acid?

  1. Linoleic acid

  2. Linolenic acid

  3. Arachidonic acid

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Arachidonic acid is not an essential fatty acid because it can be synthesized by the cells in the body from linoleic acid. All the other three are essential fatty acids.

So, the correct answer is 'Arachidonic acid'.

Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

How many of fatty acids/ fats given below do you except to have low melting points and remain as liquids in waters?
Palmitic acid, gingelly oil, arachidonic acid, stearic acid, arachidic acid, tripalmitate

  1. One

  2. Two

  3. Three

  4. Four
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Palmitic acid, arachidonic acid, stearic acid and arachidic acid are the fatty acids present in the vegetable oil. They are unsaturated fatty acid that have low melting point and remain liquid at room temperature.
So the correct answer is 'four'.
Multiple choice bio-chemistry biological molecule lipids and their function some biomolecules lipids

Which one of the following oils is having maximum content of Polyunsaturated Fatty Acids (PUFA)?

  1. Coconut oil

  2. Cottonseed oil

  3. Soyabean oil

  4. Sunflower oil
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Polyunsaturated fat is a type of dietary fat. It is one of the healthy fats, along with monounsaturated fat. Polyunsaturated fat is found in plant and animal foods, such as salmon, vegetable oils, and some nuts and seeds. Eating moderate amounts of polyunsaturated (and monounsaturated) fat in place of saturated and trans fats can benefit your health. Polyunsaturated fat is different than saturated fat and trans fat. These unhealthy fats can increase your risk for heart disease and other health problems. Polyunsaturated fats can help lower your LDL (bad) cholesterol. Cholesterol is a soft, waxy substance that can cause clogged or blocked arteries (blood vessels). Having low LDL cholesterol reduces your risk for heart disease.Polyunsaturated fats include omega-3 and omega-6 fats. These are essential fatty acids that the body needs for brain function and cell growth. Sunflower oil has higher amounts of healthy fats than others. 
So the correct option is 'sunflower oil'.
Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Which of the following chemical is released in synapse?

  1. Acetylcholine

  2. Choline

  3. Acetyl CoA

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Neurotransmitters are the chemicals that transmit the nerve impulse across the synapse. Acetylcholine is the neurotransmitter produced by cholinergic neuron. It is secreted by both pre- and post-ganglionic parasympathetic cholinergic neurons in synapse.

Thus, the correct answer is option A.

Multiple choice

Which macronutrient is used to store energy and insulate the body?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are used to store energy and insulate the body, and they provide 9 calories per gram.

Multiple choice

Which macronutrient is the body's main source of cholesterol?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are the body's main source of cholesterol, which is essential for the production of hormones and cell membranes.

Multiple choice

Which macronutrient is necessary for the production of bile, which helps to digest fats?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are necessary for the production of bile, which helps to digest fats by breaking them down into smaller molecules.

Multiple choice

Which macronutrient is necessary for the production of phospholipids, which are essential components of cell membranes?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are necessary for the production of phospholipids, which are essential components of cell membranes and help to regulate the passage of substances into and out of cells.

Multiple choice

Which macronutrient is necessary for the production of prostaglandins, which are involved in a variety of bodily functions, including inflammation and blood clotting?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are necessary for the production of prostaglandins, which are involved in a variety of bodily functions, including inflammation and blood clotting.

Multiple choice

Which macronutrient is necessary for the production of leukotrienes, which are involved in allergic reactions and asthma?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are necessary for the production of leukotrienes, which are involved in allergic reactions and asthma.

Multiple choice

Which macronutrient is necessary for the production of thromboxanes, which are involved in blood clotting?

  1. Proteins

  2. Fats

  3. Carbohydrates

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fats are necessary for the production of thromboxanes, which are involved in blood clotting.