(stick pic of fish head here) (stick pic of counter-current here) (stick pic of gills here) Counter-Current Mechanism: Water moves across gill plates in an ________ direction to blood flowing through them. So water always has a ______ oxygen conc than in the blood past which it is flowing. So oxygen will diffuse from a ____ conc in water, to a ___ conc in blood. In water there is a ______ concentration of oxygen and it diffuses slower. How Fish Breathe: Fish suck water in through mouth, into pharynx. The water then flows between gills, out through the operculum. Adaptations for diffusion: large ______ - ___ created by gill filaments covered in lamella lamella have several blood capillaries (rich b____ supply) short d_______ pathway as gill plates are very thin, so blood passing through them is close to water. high conc. G_______ between blood in lamella and water passing through.

(stick pic of insect outline here) (stick pic of tracheoles here) (draw pic of amoeba here) Conditions that favour gaseous exchange from body also cause _____ loss. So insects have an outer layer which is i__________ to water (a cuticle), however this also means no gas exchange can occur either. Therefore insects have tiny pores (s_______) to allow gaseous exchange. Spiracles are opened/closed by valves when needed. These lead into t______, strengthened by chitin for support. Trachae branch off into t__________ which provide a large ________ - _____ and create a short d_______ pathway as close to cells. Single-celled organisms Adaptations: Large _____ - _____ Thin membrane so short d_______ pathway.

(stick pic of stomata here) (draw pic of leaf shape here) (stick pic of leaf structure here) (stick pic of stomata here) Photosynthesis requires CO2 and produces O2. these gases need to be exchanged. Adaptations of a leaf: flat shape increases ______ - ____ thin to create a short ________ pathway palisade cells close to top to capture sunlight for p.syn stomata in lower epidermis to allow ____ exchange When open, stomata connect air spaces inside the mesophyll layer with the air outside. Photosynthesis: ____ diffuses into leaf, ___ diffuses out Respiration: __ diffuses into leaf, ____ diffuses out. Like with insects, plants cant keep their pores open constantly as they would lose too much water. Adaptation: _______ cells control the opening and closing of stomata, and will close if the plant is losing too much water.