Olibits / Science / Digestive System
Primary 4 Science: Digestive System Practice
Real Primary 4 Science questions on Digestive System, pulled directly from the Olibits question bank — the same questions a child would actually see, not separately written for this page.
Curriculum alignment
Science Teaching & Learning Syllabus, Primary Three to Six (MOE, 2023 syllabus)
Science is not a taught subject at P1/P2 under MOE's own syllabus — our P1/P2 Science content is offered as enrichment beyond the official syllabus, not as a claim of syllabus coverage at those grades.
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Real Digestive System practice questions
Which best describes how the digestive and circulatory systems work together to nourish the body?
The circulatory system digests food before passing it to the digestive system
The digestive system pumps blood to the small intestine for storage
The two systems work independently and never exchange substances
The digestive system breaks food into nutrients small enough to be absorbed into the blood, which the circulatory system then transports to body cells ✓
The digestive system breaks down food into small, absorbable nutrients, and the circulatory system carries these nutrients in the blood to cells throughout the body.
Why must protein in food be broken down by the digestive system before muscle cells can use it to grow and repair, instead of muscle cells using whole pieces of food directly?
The digestive system attaches directly to muscle cells without using blood
Only small nutrient molecules can pass from the digestive system into the blood, to be carried by the circulatory system to muscle cells ✓
Muscle cells absorb whole protein pieces directly from the stomach
The respiratory system converts protein into energy without any digestion
Only small, digested nutrient molecules can cross into the blood vessels of the small intestine; the circulatory system then transports these nutrients through the blood to muscle cells.
What happens immediately after digested nutrients are absorbed by the small intestine?
They remain in the small intestine permanently and are never used
They enter the blood in tiny vessels lining the intestine wall and are carried around the body by the circulatory system ✓
They are pumped directly to the kidneys to be filtered out as waste
They are immediately converted into carbon dioxide by the lungs
Digested nutrients pass through the wall of the small intestine into nearby blood vessels, where the circulatory system takes over and transports them around the body.
What is the main function of the large intestine?
To absorb water from undigested food and form solid faeces ✓
To churn food and digest protein with acid
To absorb digested nutrients into the blood
To begin breaking down food using saliva
By the time food waste reaches the large intestine, most nutrients have already been absorbed; its main role is to absorb remaining water, forming solid faeces.