Alveoli
Air sac in the lung which increases the surface area
Artery
Blood vessel that carries blood away from the heart
Atria
Upper chamber of the heart (singular - atrium)
Capillary
Small blood vessels that carry blood close to all cells in the body. They link arterioles and venules
Diffusion distance
Distance over which a molecule diffuses
Double circulatory system
A system in which blood travels through the heart twice in each circuit of the body
Exchange surface
An area where materials are interchanged
Heart
Muscular organ which pumps blood around the body
Lumen
The open channel within a tube
Phloem
Tissue that transports dissolved sugar around a plant
Potometer
Apparatus used to measure rate of water uptake in a plant
Semipermeable membrane
A membrane which only allows certain molecules to pass through it
Stomata
Small openings (pores) in a plant’s epidermis used to exchange gases (singular - stoma)
Translocation
Movement of sugars from the leaf to stores in the roots, or to growing areas of a olant
Transpiration
Loss of water form the leaves of a plant
Transpiration stream
The flow of water through a plant caused by the loss of water from a plant’s leaves
Valve
Structure that controls the direction of flow
Vein
Blood vessel that carries blood towards the heart
Ventricle
Lower chamber of the heart
Villi
Finger-like projections on the intestine wall, which increase the surface area
Xylem
Tissue that transports water around a plant