← Biology XI
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Class XI · Chapter 15 · Walkthrough

Transport — moving things around the body

01 · The heart

A double circulation

Blood passes through the heart twice per loop. The right side pumps deoxygenated blood (blue) to the lungs; it returns oxygenated to the left side, which pumps it (red) to the body. Valves keep it one-way. ▶ Play.

02 · Vessels

Arteries, veins, capillaries

Arteries carry blood away from the heart at high pressure; veins return it at low pressure (with valves); capillaries are one cell thick for fast exchange. Exception: the pulmonary artery carries deoxygenated blood.

03 · Plant transport

Xylem up, phloem either way

Xylem carries water from roots up to leaves, pulled by transpiration (blue, upward). Phloem carries sugar from leaves (source) to roots/fruits (sink) — translocation (gold). ▶ Play to watch both streams.

04 · Osmosis

Why water moves

Osmosis moves water from high water potential (dilute, left) to low water potential (concentrated, right) across a partially permeable membrane. It makes plant cells turgid — or, in strong solution, plasmolysed. ▶ Play.

🔬 Transport viewerheart
Watch the flow.