Science — AI-generated practice question

Arteries — Thick, Elastic Walls:
Arteries carry blood away from the heart under high pressure (generated by ventricular contraction). The thick, elastic walls withstand and absorb this high pressure without bursting, and their elasticity helps maintain steady blood flow.

Veins — Valves:
Veins carry blood back to the heart at low pressure. Since the blood is no longer under significant pressure, there is a risk of backflow. Valves ensure blood flows only in one direction — toward the heart — preventing it from flowing backwards.

Source: Life Processes, Section 5.4.1 — The tubes – blood vessels

---

• The textbook directly states: "arteries have thick, elastic walls" because blood emerges from the heart under high pressure, and veins "have valves that ensure blood flows only in one direction" because blood is no longer under pressure.
• Link structure → function → blood flow clearly in your answer — that's what earns full marks on a "relate" question.
• Avoid writing a long paragraph; two clearly labelled points (one per vessel) is the most exam-efficient format here.