Plants do “breathe”, but not with lungs or by sucking air in and out like animals. Instead, gases quietly drift in and out of tiny pores and air spaces in their tissues all the time.

Simple answer

  • Plants take in carbon dioxide and release oxygen during photosynthesis in the light.
  • They also take in oxygen and release carbon dioxide during respiration , day and night.
  • The gas exchange happens mainly through tiny pores called stomata on leaves and lenticels on stems, plus surfaces of roots in the soil.
  • Gases move by diffusion (from where there is more to where there is less), not by muscles or pumping.

Mini-section 1: The “lungs” of a plant

You can think of a leaf as having its own built‑in air‑channel system, like a sponge full of tiny tunnels.

  • Most leaves are covered with thousands of microscopic pores called stomata (singular: stoma), usually on the underside.
  • Inside the leaf, cells are loosely packed with big air spaces, forming channels that let gases spread through the tissue, sometimes described as the plant’s “airways” or “lungs.”
  • Stems of woody plants have small breaks in the bark called lenticels that let gases move in and out to the living cells underneath.

If a leaf had a cartoon speech bubble, it wouldn’t be “inhale–exhale” like us; it would be more like “gases wandering in and out whenever the concentration changes.”

Mini-section 2: How gases move in and out

Plants don’t actively pull air in; they rely on physics.

  • Gases move by diffusion : from an area of high concentration to an area of low concentration.
  • When photosynthesis uses up carbon dioxide inside the leaf, the CO₂ level drops, so more CO₂ diffuses in through the stomata from the outside air.
  • When oxygen builds up inside (from photosynthesis or from respiration), it diffuses out through the same pores.
  • There is no breathing “cycle” like inhale–exhale; diffusion is continuous and automatically adjusts as conditions change.

Mini-section 3: Photosynthesis vs. respiration (day and night)

Two key processes overlap and share the same gas‑exchange routes.

  • Photosynthesis (in light):
    • Uses carbon dioxide and water to make glucose and oxygen.
* CO₂ goes **in** , O₂ comes **out** via stomata.
  • Respiration (all the time):
    • Uses oxygen to break down glucose for energy, releasing carbon dioxide and water.
* O₂ goes **in** , CO₂ comes **out** through stomata, lenticels, and root surfaces.
  • During a bright day, photosynthesis is usually stronger than respiration, so the plant is a net consumer of CO₂ and producer of O₂.
  • At night, photosynthesis stops, but respiration continues, so the plant takes in O₂ and releases CO₂.

Mini-section 4: How different parts “breathe”

Each part of the plant handles its own gas exchange.

  1. Leaves
    • Main site of both photosynthesis and a lot of respiration.
 * Stomata open and close using special **guard cells** , balancing gas exchange with water loss.

 * When stomata are open, CO₂, O₂, and water vapor all move in or out by diffusion.
  1. Stems
    • Green, soft stems can exchange gases through their surface and any stomata present.
 * Woody stems use lenticels—tiny corky spots that look like dots or lines on bark—to let O₂ in and CO₂ out.
  1. Roots
    • Roots need oxygen for respiration to power water and nutrient uptake.
 * They get O₂ from air spaces between soil particles; the gases diffuse across the root surface.

 * Waterlogged or compacted soil has less air, so roots can “suffocate” and the plant may grow poorly or die.

Mini-section 5: Quick facts and common misconceptions

  • Plants do not have lungs, a diaphragm, or a heartbeat, so they don’t “breathe in and out” in a rhythmic way like humans.
  • Both animals and plants perform cellular respiration in mitochondria to release energy from glucose using oxygen.
  • The same pores (stomata) that let gases move also control water loss, so plants constantly juggle getting CO₂ with not drying out.
  • Large forests and many houseplants can significantly affect local CO₂ and O₂ levels, which is one reason trees are so important for the environment.

Mini FAQ style recap

  • So, how do plants “breathe in and out”?
    By passive diffusion of gases through stomata, lenticels, and root surfaces—no pumping, just movement from high to low concentration.
  • What goes in and what comes out?
    • In light: Mostly CO₂ in, O₂ out (plus respiration happening quietly in the background).
* In dark: O₂ in, CO₂ out from respiration only.
  • Why does this matter for us?
    Because the same gas‑exchange system that lets plants “breathe” is what supplies much of the world’s oxygen and helps balance atmospheric carbon dioxide.

Information gathered from public forums or data available on the internet and portrayed here.