Tag: biomolecules: chemical constituents of living cells

Quizzes (7) Questions (113)

Questions Related to biomolecules: chemical constituents of living cells

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Which of the following derived lipids helps in emulsifications and encapsulation?

  1. Lecithins

  2. Cephalins

  3. Carotenoids

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Lecithin is a group of yellow-brownish fatty substances present in animal and plant tissues.In the pharmaceutical industry, it is used in emulsifications and encapsulation of drugs and is a good dispersing agent. Thus the correct answer is option A.

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

The phospholipid which is mainly found in the white matter of brain and spinal chord is 

  1. Lecithins

  2. Cephalins

  3. Waxes

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

Phosphatidylethanolamines are phospholipids found in all living cells, They are found mainly in the nervous tissue such as the white matter of the brain, nerves, neural tissue and in the spinal cord. 

So, the correct answer is option D.

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Which of the following lipid is mainly used for membrane biogenesis?

  1. Carotenoids

  2. Terpenes

  3. Phospholipids

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

Membrane biogenesis is structuring/rebuilding/repairing of the cell membrane. As the cell membrane is made of a bilayer of phospholipids embedded with proteins.It is a process carried out by the cell with the help of smooth endoplasmic reticulum (SER) and Golgi apparatus (GA). Where the SER synthesizes lipids which are added with phosphate group and modified to phospholipids by the process of phosphorylation in the GA and transported through vesicles to the cell membrane.

So, the correct answer is 'Phospholipids'

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Which of the following lipid act as a precursor of bile acids, Vitamin D and steroids?

  1. Phosphoglycerides

  2. Cholesterol

  3. Phospholipids

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

De novo synthesis of cholesterol from acetyl-CoA takes place in the liver. Cholesterol is an essential metabolite for the normal functioning of the endocrine system, regulation of cell membrane processes, and absorption of dietary lipids. They are important structural components of membranes. Cholesterol also serves as precursor for the synthesis of steroid hormones, vitamin D, and bile salts which are important in fat absorption from the small intestine into the blood circulatory system and secretion of liver waste products through feces. Thus the correct answer is option B.

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Commonly candles are prepared from

  1. Bee's wax

  2. Paraffin wax

  3. Stearic acid

  4. Both B and C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Commonly candles are prepared from stearic acid and paraffin wax. Candles that made from paraffin wax only burn quicker than those made from paraffin wax and stearic acid together.

Thus, the correct answer is option D.

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Source of turpentine oil is

  1. Bark of Cinchona

  2. Lichen

  3. Gymnospermous wood

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

Turpentine oil is an oil which is a volatile oil which is mainly obtained from pines a gymnospermic plant. It is obtained by distillation of resin. Terpenes are the derivative of terpene oil. It is used for thinning oil based paints. It is a very good source of organic synthesis. It is highly viscous in nature. The solid material left behind after distillation is known as rosin.

So, the correct answer is option C.

Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Prostaglandins are made from

  1. Steroid

  2. Carbohydrate

  3. Amino acid

  4. Fatty acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Arachidonic acid is a polyunsaturated omega-6 fatty acid. It is present in the phospholipids and helps in the formation of membranes. It is the most abundant fatty acid in the brain. It is a precursor for the synthesis of prostaglandins. The prostaglandins synthesized is PG$ _2$. They are autocrine and paracrine lipid mediators that act upon platelets, endothelium, uterine and mast cells. 
So, the correct answer is option D.
Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

Prostaglandins synthesized from

  1. Amino acids

  2. Fatty acids

  3. Carbohydrates

  4. Steroids
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Prostaglandins are synthesized by arachidonic acid. Arachidonic acid is a polyunsaturated omega-6 fatty acid. It is present in the phospholipids and helps in the formation of membranes. 
The prostaglandins synthesized is PG$ _2$. They are autocrine and paracrine lipid mediators that act upon platelets, endothelium, uterine and mast cells. It belongs to a class of fatty acid derivative.
So, the correct answer is option B.
Multiple choice bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

What is true of membrane lipids and proteins?

  1. None can flip-flop

  2. Both can flip-flop

  3. Proteins can flip-flop but lipids cannot.

  4. Lipids flip-flop but proteins rarely flip-flop
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Lipid bilayer of the cell membrane contains hydrophilic head groups facing outward and hydrophobic tails facing each other. The transport of phospholipids and lipid-linked oligosaccharides is difficult to achieve due to this bipolar nature. The transmembrane lipid transporter proteins called flippases transport lipids across cell membrane through transverse diffusion by flipping their orientation. Floppases transport in reverse direction. In mammals, this affects various processes such as blood coagulation, immune recognition, and programmed cell death.Most protein molecules do not flipflop due to their extensive polar regions, which are unfavorable in the hydrophobic core of the membrane.

Option D is correct.