Biological Molecules
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Carbohydrates, lipids and proteins
SubtopicCarbohydrates, lipids and proteins under Biological Molecules for Grade 11 IGCSE.
Preview questions (no answers)
- 1.
Which of these elements is sometimes found in proteins (in the R-group of certain amino acids) but never in carbohydrates?
A.Carbon
B.Hydrogen
C.Oxygen
D.Sulfur
- 2.
What color is Benedict's solution before it is added to a food sample?
A.Orange
B.Blue
C.Colorless
D.Red
- 3.
Which molecule consists of many glucose units linked in a way that makes it indigestible for humans but provides fiber?
A.Starch
B.Glycogen
C.Cellulose
D.Sucrose
Download the worksheet for Biological Molecules - Carbohydrates, lipids and proteins to practice offline. It includes additional chapter-level practice questions.
Structure of DNA
SubtopicStructure of DNA under Biological Molecules for Grade 11 IGCSE.
Preview questions (no answers)
- 1.
Which chemical base is complementary to Thymine?
A.Guanine
B.Cytosine
C.Adenine
D.Uracil
- 2.
What provides the vertical stability for a single strand of DNA?
A.Hydrogen bonds between bases
B.Covalent bonds in the sugar-phosphate backbone
C.Ionic bonds between strands
D.Weak physical contact
- 3.
Which component of the nucleotide contains the element Nitrogen?
A.Phosphate
B.Sugar
C.Base
D.Both sugar and phosphate
Download the worksheet for Biological Molecules - Structure of DNA to practice offline. It includes additional chapter-level practice questions.
Chemical tests for molecules
SubtopicChemical tests for molecules under Biological Molecules for Grade 11 IGCSE.
Preview questions (no answers)
- 1.
If iodine solution is dropped onto a sample of pure vegetable oil, what color will the iodine remain?
A.Blue-black
B.Orange-brown
C.Clear
D.Purple
- 2.
Which reagent should be selected to test for the presence of glucose ()?
A.Iodine solution
B.Benedict's solution
C.Biuret reagent
D.DCPIP
- 3.
In the emulsion test, what change occurs to the liquid once the ethanol extract is added to water?
A.It turns dark blue
B.It becomes a cloudy/milky emulsion
C.It turns bright purple
D.It stays completely clear
Download the worksheet for Biological Molecules - Chemical tests for molecules to practice offline. It includes additional chapter-level practice questions.