L26 Animal Circulation and Gas Exchange Flashcards
who proposed the correct blood flow pattern 400 years ago?
William Harvey
what is a solution for volume to surface area ratios?
circulation
how does O2 and CO2 travel around body without circulation system?
diffusion
what simple animals do not have circulatory systems?
cnidaria, sponges and flatworms
What are the functions associated with Circulatory system?
1) Respiratory gas transport
2) nutrient and waste transport
3) communication via hormones
4) heat transfer
what is an open circulatory system?
fluid containing transport materials is open to the tissues, it is pumped into tubular heart and then to tissues and back again
what is the fluid called in open circulatory systems?
hemolymph
What is the hearts function?
1) transport fluid around body
2) generate flow and pressure
3) muscular contraction
4) regulation of stroke volume and rate
what organism has an open circulatory system?
fish
what is an advantage of close circulatory system?
creates higher flow of blood and blood pressure - better metabolism
what is the blood composed of?
45% red and white blood cells, 55% plasma
what is haemoglobin?
respiratory pigment found in erthrocytes
how do red blood cells get energy if they have no mitochondria?
they respire anaerobically
what is haemocyanin?
protein in invertebrates that transports O2
Why do fish have gills in relation to gas exchange?
increase surface area of exchange to get O2 in and CO2 out
what is non-directional ventilation?
gasesous exchange occurs in an unpredictible area example eel skin
what is tidal ventilation?
O2 and CO2 leave and enter through the same points
what is unidirectional ventilation?
one way flow of gaseous exchange example fish (most efficient)
water flows through mouth through gills and back out to oxygen
how do arthropods complete gaseous exchange?
pores with a system of tubes called trachea via diffusion
what is different about breathing under water?
1) 20 times less O2 per volume of water compared to air
2) water is more viscous than air ,ventilation requires more energy
3) rate of diffusion is much slower
how do lamprey fish breathe?
mouths closed, expand and contract head ‘branchobasket’ , water flows in and out of gills
what is ram ventilation?
animals constantly swim forward with mouth open trying to get oxygen
what is a counter-current exchange system?
blood flowing in one direction, oxygen flowing in another - more opportunity for gasses to exchange between
how does counter-current allow lots of diffusion?
it has a continuous gasesous exchange gradient