Y9 Biology - exchange surface

Exchange Surface Effectiveness(increased by …, …, good …/…, and …gradients)

Increased by large surface area, thin barrier, good blood/air supply, and steep concentration gradients

Large Surface Area(more …, increasing the … exchange)

More space for diffusion, increasing the rate of exchange

Thin Exchange Surface(short…quickly)

Short diffusion distance so substances move quickly

Steep Concentration Gradient(maintained by … or … to keep diffusion…)

Maintained by good ventilation or blood flow to keep diffusion fast

Good Blood Supply(blood carries…, maintaining …)

Blood carries substances away quickly, maintaining steep gradients

Ventilation (moves … to maintain … differences)

Moves fresh air/water in and out to maintain concentration differences

Small Intestine Adaptation(very long…absorption)

Very long tube increases surface area for absorption

Villi(finger-like … that … surface area)

Finger‑like projections that massively increase surface area

Microvilli(tiny… villi cells… surface area)

Tiny folds on villi cells that further increase surface area

Thin Epithelium (Intestine)(… wall gives a … distance)

One‑cell‑thick wall gives a short diffusion distance

Rich Capillary Network (Intestine)(maintains … for … and …acids)

Maintains steep concentration gradients for glucose and amino acids

Lacteal(absorbs … And …m aiding efficient transport)

Absorbs fatty acids and glycerol, aiding efficient transport

Lung Adaptation(lungs contain … giving a … area)

Lungs contain millions of alveoli giving a huge surface area

Alveoli (tiny … walls … gas exchange)

Tiny air sacs with thin walls for rapid gas exchange

Thin Alveolar Wall (One … shorten … distance)

One cell thick to shorten diffusion distance

Moist Surface (Lungs) (Allows … before diffusing)

Allows gases to dissolve before diffusing

Rich Blood Supply (Lungs)(Capillaries … and … gradients)

Capillaries maintain steep oxygen and carbon dioxide gradients

Ventilation of Lungs(constant… concentration…)

Constant airflow keeps concentration gradients steep

Gill Adaptation(Gill filaments…for gas exchange in fish)

Gill filaments provide a large surface area for gas exchange in fish

Gill Lamellae(…further and contain …)

Increase surface area further and contain many capillaries

Thin Surface (Gills)(Short … for … and …)

Short diffusion distance for oxygen and carbon dioxide

Counter‑Current Flow(… and … flow in … directions to … along the whole gill)

Water and blood flow in opposite directions to maintain a steep gradient along the whole gill

Good Blood Supply (Gills)(Capillaries…away quickly)

Capillaries carry oxygen away quickly

Leaf Adaptation(Large…more … and …)

Large surface area to absorb more light and carbon dioxide

Thin Leaf(Short … gases)

Short diffusion distance for gases

Air Spaces in Spongy Mesophyll(allow…inside the leaf)

Allow gases to diffuse easily inside the leaf

Stomata(Pores that open to … and close to …)

Pores that open to allow gas exchange and close to reduce water loss

Guard Cells(control … to regulate …)

Control stomata opening to regulate gas exchange

Moist Leaf Surface(allows gases to … before …)

Allows gases to dissolve before diffusing into cells