浸透圧

• Reading: しんとうあつ
• Romaji: shintoatsu
• Kanji breakdown: 浸 (shin) — soak | 透 (to) — penetrate | 圧 (atsu) — pressure
• Pronunciation: /ɕin.to.ɯ.a.tsɯ/

Meaning

Osmotic pressure; the pressure required to prevent the flow of solvent across a semipermeable membrane separating solutions of different concentration.

A key concept in cell biology, physiology, and food science. Cells placed in a solution with higher osmotic pressure than their interior will shrink (plasmolysis); those in lower osmotic pressure will swell and may burst. Isotonic solutions (等張液) match the body's osmotic pressure, making them suitable for IV fluids.

Examples

1. 赤血球は純水に入れると浸透圧の差によって膨張し、やがて破裂する。 When red blood cells are placed in pure water, they swell due to the difference in osmotic pressure and eventually burst.
2. 点滴液は体液と同じ浸透圧に調整されており、細胞への影響を最小限に抑える。 IV fluids are adjusted to the same osmotic pressure as bodily fluids, minimising their effect on cells.
3. 塩分濃度が高い海水中では、浸透圧の関係で水分が体外に奪われてしまう。 In seawater with a high salt concentration, the osmotic relationship causes water to be drawn out of the body.

Usage Guide

Context: biology, physiology, chemistry, medicine

Tone: technical

Origin & History

Compound of 浸透 (shinto, osmosis/permeation) and 圧 (atsu, pressure). 浸透 itself is from 浸 (soak) and 透 (penetrate), describing the passage of liquid through a membrane.

Cultural Context

Era: Modern

Generation: Biology students and medical professionals

Social background: Academic