How Do Plants Absorb Water and Nutrients?
Video showing how roots take up substances from the soil via osmosis, diffusion, and active transport.
Encyclopædia Britannica, Inc.
-
Encyclopædia Britannica, Inc.Apes have unique personalities and preferences—just like humans.Media Editor: Lee Goldstein
-
Encyclopædia Britannica, Inc.If some dinosaurs had feathers, does that make them birds?
-
Encyclopædia Britannica, Inc.Every minute, multiple liters of air are cycled through your lungs.
-
Encyclopædia Britannica, Inc.Plants can reproduce asexually in a variety of ways. Learn about bulb, gemma, plantlet, and cutting forms of asexual plant reproduction.
-
Encyclopædia Britannica, Inc.During the dark reaction (light-independent stage) of photosynthesis, sugars such as glucose are created from carbon dioxide and water using adenosine triphosphate (ATP).
-
Archival footage supplied by the Internet Moving Images Archive (at archive.org) in association with Prelinger ArchivesAugusta Savage sculpting, in an excerpt from A Study of Negro Artists, a silent film produced by the Harmon Foundation and released in the 1930s that features many artists active during the Harlem Renaissance.
-
Encyclopædia Britannica, Inc.Some of the different ways plants are pollinated.
Transcript
NARRATOR: In most land plants, oxygen and carbon dioxide enter through the leaves, while water and mineral salts enter through the root system. Substances can move into the root in several ways, with the principal method being osmosis.
During osmosis free-water molecules pass from the soil into the epidermal cells, using the root-hair membrane. Looking at this process at the molecular level, we see that the small water molecules pass easily through the selectively permeable membrane of the epidermal cells.
Diffusion of mineral salts occurs at the same time. Facilitated diffusion occurs when important molecules pass through the membranes via special holes called channels.
Active transport of other molecules may also take place in the root hair, depending on the needs of the plant. Active transport requires energy, as the required molecules must be pumped across the membrane against their concentration gradient.
During osmosis free-water molecules pass from the soil into the epidermal cells, using the root-hair membrane. Looking at this process at the molecular level, we see that the small water molecules pass easily through the selectively permeable membrane of the epidermal cells.
Diffusion of mineral salts occurs at the same time. Facilitated diffusion occurs when important molecules pass through the membranes via special holes called channels.
Active transport of other molecules may also take place in the root hair, depending on the needs of the plant. Active transport requires energy, as the required molecules must be pumped across the membrane against their concentration gradient.