2.4 water & its functions Flashcards
what does combined hydrogen bonds causes water to do?
stick together
explain why, in terms of chemical properties why water has a large specific heat capacity.
combined hydrogen bonds causes H2O molecules to stick togethr & therefore harder to seperate
how does H2O having a high latent heat of vapourisation help?
used in sweating & transpiration
- body heat is used to evaporate sweat from skin surface
-> cools organism as H2O vapour takes heat energy away
how could water act as a temperature buffer?
lots ofheat need to be gained / lost before temperature changes -> temperature buffer
how are cohesion & adhesion in water useful to organisms?
allows H2O to be pulled up in a tube due to capillary action
how is water used in metabolism?
- hydrolysis & condensation reactions
- medium for chemical reactions
- raw material for photosynthesis
list 4 substances that water could be used as a solvent to.
- CO2 & O2
- wastes (eg. urea, NH3)
- amino acids, ATP, monosaccharides
- enzymes
how is the transparancy of water important to plants & animals?
- aquatic plants could get light for photosynthesis
- light passes from eyeball -> retina
why is water being a liquid at room temperature important to living organisms?
mass transport: xylem in plants & blood plasma in animals
how is water not being able to be compressed important?
acts as hydrostatic skeleton: keeps turgor pressure in plant cells & provide support
what are inorganic ions?
not carbon based
where is Fe2+ used?
haemoglobin, binds to O2
where is PO4 3- used?
DNA & RNA, ATP synthesis
where is H+ used?
pH & photosynthesis/respiration
where is Na+ used?
co-transport in the ileum & nerve transmission
