Science — AI-generated practice question

The human transport system consists of the following components:

1. Blood: A fluid connective tissue made of plasma and blood cells. Plasma transports food, CO₂, and nitrogenous wastes in dissolved form; RBCs carry oxygen.

1. Heart: A muscular pumping organ with four chambers. It pumps oxygenated blood to the body and deoxygenated blood to the lungs, maintaining double circulation.

1. Arteries: Thick-walled, elastic blood vessels that carry blood away from the heart to various organs under high pressure.

1. Veins: Blood vessels that collect blood from organs and return it to the heart; have valves to prevent backflow.

1. Capillaries: Thin-walled (one-cell thick) vessels where exchange of nutrients, gases, and wastes occurs between blood and body cells.

1. Platelets: Plug leaks in damaged blood vessels by helping clot the blood, preventing blood loss.

1. Lymph: Colourless fluid that drains excess fluid from intercellular spaces back into blood and carries absorbed fats from the intestine.

Source: Chapter 5, Section 5.4.1

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The examiner expects all major components named with one clear function each. Seven components are identifiable from the passage — listing 5–6 with correct functions scores full marks. Avoid mixing up artery/vein functions; remember arteries carry blood away from the heart, veins bring it back. Platelets and lymph are commonly forgotten — include them for a complete answer.