HO: 4-6 Flashcards
(28 cards)
xerophyte
species of plant that has adapted to survive in an environment with little water, such as desert or coastal sand dunes
3 main groups of xerophytes
succulents, sclerophylls, ephemerals
desiccation
drying out
physiological adaptations of xerophytes
ephemerals, hibernation, leaves that turn/curl to avoid heat, closed stomata
structural adaptations of xerophytes
succulents, long tap roots, arrangement of leaves/branches, clumping growth, silvery hairy surface of leaves, rolled leaves, sunken stomata, reduced leaves, low stomata density, thick waxy cuticle, ephemeral seeds
halophytes
salt-tolerant plants
halophyte adaptations
cellular sequestration, tissue partitioning, root level exclusion, salt excretion, altered flowering schedule
osmoregulation
the regulation of salt and water content in an organism
osmoregulation of a fish in salt water
hypertonic environment. Problem - lose water, gain salts. drinks salt water, produces small volume of concentrated urine and secretes salts from gills to combat this
osmoregulation of a fish in fresh water
hypotonic environment. Problem - gain water, lose salts. doesn’t drink water, produces large volume of dilute urine and takes up salt from gills to combat this
osmoregulation of an insect
hard body covering (exoskeleton), respiratory surface within the body and uric acid pellets containing little water are produced to prevent water loss
osmoregulation of a reptile
tough outer body covering of scales and excrete uric acid to prevent water loss, salt secreting glands
osmoregulation of a mammal
liver produces urea, sweating releases water and excess salts, behavioural adaptations to avoid water loss
osmoregulation of marine birds
drink salt water to gain water, secrete excess salts through salt glands near their eyes
protozoan contractile vacuole excretion
concentrated solutes inside cell (gain water), contractile vacuoles pump out excess water
insect malplghlan tubule excretion
system of tubules excrete waste products as uric acid and absorb the water from the wastes
ammonium waste
high toxicity, immediate excretion, requires a lot of water to dilute and wash away
urea waste
medium toxicity, must be excreted after a while, requires some water to excrete
uric acid waste
low toxicity, can be retained in body for a long time, requires very little water to excrete (paste)
an animal surrounded by water produces what waste?
ammonia
an animal surrounded by land produces what waste?
uric acid
an animal with medium access to water produces what waste?
urea
ammonia requires how much energy to produce?
very little
uric acid and urea require how much energy to produce?
a lot
