lec 3 (hyper-hypo)

Question 1

how do terrestrial invertabreates conserve water

Answer 1

they have a waxy epicuticle

live in moist environments (hygrophiles)

get water from food, drinking, soil or air

metabolic catabolism of sugar which releases water

Question 2

4 main types of regulatory organs in invertabrates

Answer 2

contractile vacuoles

nephridial glands

antennal or green glands

malphighian tubules

Question 3

contractile vacuoles (like in sponges)

Answer 3

water comes in…

pores open

vacuole contracts

contraction expels water out of the cell

racial canals take up water from surrounding cytoplasm

water moves from radial canals to the vacuole

Question 4

nephridia- proto (first) and meta, found in flatworms

Answer 4

they have an internal tube network that are closed at the end

the tube network is connected to the environment by nephridophores

ends of the tubules is a cap cell

tubules are nephridoducts

Question 5

what are the two types of nephridia

Answer 5

flame cells- cap cell has several flagella

solenocytes- cep cell has one flagellum

Question 6

what does the flagella do

Answer 6

beating flagella draws extracellular fluid through the perforations,

drivin along the tubule and ions quickly reabosrbed,

urine is collected in the ducts and released

Question 7

nephridia: metanephridia

Answer 7

internalised tubules which terminate with the exterior nephridiopore

ciliated funnel called nephrostome which opens into the coelomic cavity

coelomic fluid passed into the collecting tubule

Question 8

arthropopds

Answer 8

have an open circulatory system

extrate ammonium ions accors their gills

they have antennal or green glands (these things mean the same thing?)

mainly excrete uric acid, urea

Question 9

arthropods- antannal glands

Answer 9

the closed end sac leads to the labyrinth

nephridial canal leads to the bladder which connects to the environment by the nephropore

end sac contains sort of podocytes

ultrafiltration of the haemolymph occurs forcing smaller molecules into the end sac

urine is modified in the labrynth and the nephridial canal

Question 10

insects- malipiphian tubules

Answer 10

they have blind ending tubules extending from the mid-gut

k is activley secreted into the tubule, water follows passivley

primary urine flows into the hind gut

hind gut water reaborbed through active reabsorbtion of solutes

precipitation facilitates withdrawal of more water from the hind gut