describe adaptations of a range of terrestrial Australian plants that assist in minimising water loss use available evidence to explain the relationship between the conservation of water and the production and excretion of concentrated nitrogenous wastes in a range of Australian insects and terrestrial mammals These organisms directly release ammonia into the Aquatic Animals and Fish: environment. This uses a lot of water, but they have no need to conserve it. Ammonia is very water soluble and is excreted through the gills. Releasing ammonia would be unfeasible due to lack of Terrestrial Animals: water. Instead, land-dwellers change ammonia into less toxic forms and release it periodically. Mammals change it into UREA and release it as urine. Birds change ammonia into URIC ACID, a whitish paste which uses Birds: hardly any water. This is lighter than using urea, and helps in flight. process and analyse information from secondary sources and use available evidence to discuss processes used by different plants for salt regulation in saline environments Maintaining Salt Concentrations in Plants Most plants cannot tolerate high salt concentrations in the root zone as it leads to water stress. The salt accumulates in its leaves and is toxic. Enzymes are inhibited by Na+ ions. are plants adapted to living in environments. They are able to Halophytes tolerate higher levels of salt than any other plants or they have special mechanisms to control their levels of salt. Three different mechanisms are salt exclusion, salt excretion and salt accumulation. Salt excluders prevent the entry of salt into their root systems by filtration. – This is a passive process that does not use energy and relies on the transpiration stream. It can be very successful. Example: The grey mangrove can exclude 95% of their salt via the filtration system in its Avicenna marina roots and lower stems. Other mangroves that rely on this system are the red mangrove Rhizophora and the orange mangrove stylosa Bruguiera gymnorrhiza. red mangrove Rhizophora stylosa
describe adaptations of a range of terrestrial Australian plants that assist in minimising water loss use available evidence to explain the relationship between the conservation of water and the production and excretion of concentrated nitrogenous wastes in a range of Australian insects and terrestrial mammals Aquatic Animals and Fish: These organisms directly release ammonia into the environment. This uses a lot of water, but they have no need to conserve it. Ammonia is very water soluble and is excreted through the gills. Terrestrial Animals: Releasing ammonia would be unfeasible due to lack of water. Instead, land-dwellers change ammonia into less toxic forms and release it periodically. Mammals change it into UREA and release it as urine. Birds: Birds change ammonia into URIC ACID, a whitish paste which uses hardly any water. This is lighter than using urea, and helps in flight. process and analyse information from secondary sources and use available evidence to discuss processes used by different plants for salt regulation in saline environments Maintaining Salt Concentrations in Plants Most plants cannot tolerate high salt concentrations in the root zone as it leads to water stress. The salt accumulates in its leaves and is toxic. Enzymes are inhibited by Na+ ions. Halophytes are plants adapted to living in environments. They are able to tolerate higher levels of salt than any other plants or they have special mechanisms to control their levels of salt. Three different mechanisms are salt exclusion, salt excretion and salt accumulation. Salt excluders – prevent the entry of salt into their root systems by filtration. This is a passive process that does not use energy and relies on the transpiration stream. It can be very successful. Example: The grey mangrove Avicenna marina can exclude 95% of their salt via the filtration system in its roots and lower stems. Other mangroves that rely on this system are the red mangrove Rhizophora stylosa and the orange mangrove Bruguiera gymnorrhiza. red mangrove Rhizophora stylosa
msb_part_3.docx