EduNinjaCAIE IGCSE Biology Extended 4.1 Biological molecules question practice helps you revise this syllabus point with the course map in view. Use this page to focus on one topic, check the style of questions available, and connect each attempt back to the knowledge area it is testing.
EduNinja keeps Biology practice aligned to CAIE at Extended level, so you can move from topic review into exam-style question bank work without losing the syllabus structure. Start with a small set, mark the weak steps, then return to nearby topic links when a definition, graph, calculation, or explanation needs repair.
Fig. 1.1 and Fig. 1.2 show two images of villi.
Fig. 1.1 shows a surface view of many villi viewed through a scanning electron microscope.
Fig. 1.2 shows a section of one villus viewed through a light microscope.
Fig. 1.1
Fig. 1.2
Villi are found in the small intestine.
Amino acids are an example of a type of nutrient transported in the blood.
State two examples of larger molecules found in cells that are made from amino acids.
1
2
Two functions of the alimentary canal are mechanical digestion and chemical digestion.
Substances that are absorbed from the alimentary canal may enter cells and become part of the cells.
State the storage carbohydrate made from glucose in liver cells.
The main component of milk is a liquid that is an important solvent in the body.
State the name of this solvent.
Enzymes are used in genetic engineering.
The process of genetic engineering often starts with the steps shown in Fig. 1.1.
Fig. 1.1
State the sequence of bases on the lower strand of the DNA molecule in step 1.
Enzymes are catalysts.
Enzymes are proteins.
State the names of the chemical elements found in all proteins.
Which diagram shows the structure of DNA?
The bases on one of the strands of a DNA molecule have the sequence shown.
A-A-T-C-T-G
What is the corresponding sequence of bases on the other strand?
A-A-T-C-T-G
C-C-G-A-G-T
G-G-C-T-C-A
T-T-A-G-A-C
The diagram shows the order of bases along part of one strand of DNA.
What is the order of bases on the corresponding part of the other strand?
A-C-T-T-A-G-A-T
C-A-G-G-C-T-C-G
T-A-G-A-T-T-C-A
T-G-A-A-T-C-T-A
The data show the concentrations of sugar and starch in an onion.
The onion is tested with Benedict's solution and iodine solution.
Which set of results is correct?
Benedict's
solution
iodine
solution
blue
blue-black
blue
brown
brick red
blue-black
brick red
brown
The data show the concentrations of sugar and starch in an onion.
The onion is tested with Benedict's solution and iodine solution.
Which set of results is correct?
Benedict's
solution
iodine
solution
blue
blue-black
blue
brown
brick red
blue-black
brick red
brown