circulation and ventilation

Question 1

challenges of taking up oxygen, and its solution

Answer 1

delivering o2 to the cells are too slow

cells are in direct contact with environment

evolve a circulatory system to deliver o2

Question 2

limitations of not having respiratory organs or a circulatory system

Answer 2

low metabolic rate, small (large sa:v)

Question 3

what are the functions of a circulatory system?

Answer 3

deliver o2 to cells/organs

remove co2

transport heat

enable movement

Question 4

what does a circulatory system need

Answer 4

circulatory fluid

interconnecting tubes

pump- contractile mechanism

Question 5

two main types of circulatory system

Answer 5

open, closed

Question 6

open circulatory systems

Answer 6

consosts of a heart with vessels which are open

movement assists with the flow

flow into spaces between sinuses and lacunae tissues

Question 7

what is circulatory fluid called

Answer 7

haemolymph

Question 8

what happens when the heart contracts

Answer 8

haemolymph is driven into the arteries and out into the sinnuses and lacunae

ostia (openings) close

during relaxation ligaments explans and the heart returns to original volume

ostia open bringing in haemolymph from the pericardial sinus

Question 9

advantages of open circulatory system

Answer 9

lower hydrostatic pressure, reduced energy costs

Question 10

closed circulatory systems

Answer 10

circulatory fluid is contained within a network of vessels

heart/s contract and blood is driven into large vessels then smaller vessels, passing throught tissues and organs

Question 11

advantages of closed circulatory systems

Answer 11

increase hydrostatic pressure

regulate distribution of blood

Question 12

octopus and squid

Answer 12

3 hears, systemic heart and two smaller branchial hearts

allows for re pressurisation of blood prior to entering the gills and allows for fast blood flow rates