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Flashcards in bevan Deck (35)
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1
Q

why do animals lose heat more quickly in water than in air

A

water has a higher thermal conductivity

2
Q

what happens when water temperature increases

A

body temperature increases, oxygen demand increases BUT oxygen content decreases

3
Q

why does aquatic ventilation use passive through through systems and not tidal

discuss some examples of flow through systems

A

because too much energy would be required to accelerate and deaccelerate water into an organism (tidal)

polycheate worms have external tenticle fans or external gill tufts

sea stars have tubed feet with gill function

4
Q

discuss an aquatic animal which performs tidal ventilation

A

sea cucumber (Holothurian echinoderm) draws water in, oxygen diffuses across respiritory trees before water is pushed back out of the same whole

5
Q

discuss an aquatic animal that does active oxgen extraction using a through flow system

A

cephalopods.

squids are hard to work with so octopuses are used for experimentation

water in drawn in over gills through a slit before being forced out of a siphon

6
Q

what is the process by which fish do respiritory exchange

A

opercular pumping
water is gulped into mouth, which moves into the operculum cavity. when the cavity is compressed the water is forced out through gills.

7
Q

discuss the structure of fish gills

A

gills consist of many tube like structures called filaments, which have folds on their surface called lamellae. blood flows through the lamellae in a counter current direction to water

8
Q

what ventilaiton method is done by fish swimming at high speeds

how is this different to normal ventilation

A

ram ventilation

operculum cavity doesnt need to be compressed

this process is less metabolically demanding than normal ventilation

9
Q

which fish have a large SA;weight ratio

A

those who are very active, such as mackral

10
Q

how do terrestrial animals ensure their respiritory surfaces are always kept moist

A

stay in mosit humid areas or fully enclose their respiritory structures

11
Q

do terrestrial animals perform through flow or tidal ventilation

A

mostly tidal

12
Q

discuss different ventilation methods displayed by terrestrial animals

A

insects have tracheae and spiricles.

lungfish, amphibians and some reptiles use positive pressure systems. compressing a buccel cavity to force air through respiratory surface

crocodiles and mammals contract muscles which increases the volume of the lungs and create negative pressure which draws air in.

13
Q

what is a possibly explanation for the fact that birds are better at oxygen extraction compared to similar sized mammals

A

this system evolved perhaps due to the fact that birds fly at higher altitudes than mamals (over mountains etc)

14
Q

apart from birds, which is one other group of animals which also perform uni directional ventilation

A

crocodiles have areas of unidirectional flow

15
Q

what are the 4 types of circulatory system

A

systemic; to and from body tissues (high pressure)
pulmonary; to and from lungs (low pressure)
open; blood not contianed in blood vessels or only partially contained in blood vessels
closed; the blood is always contained in the heart or pumping systems

16
Q

what is an auricle

A

a cone shaped pouch is the atrium of vertebrates that increases blood holding capacity

17
Q

describe structural differences between the vessels in the arterial and venous sytems

A

arterial system vessels have a narrow lumen to maintain high pressure, and a thick layer of smooth muscle, elastin and collagen for stregth to withstand the pressure

the vessels in the venous systems have a wide lumen, and thin walls containing little smooth muscle etc because high pressure is not needed
the venous system has valves present to prevent backflow

18
Q

how is the flow of blood altered

A

changing pressure or resistance, for example changing the lumen diameter of the vessel by vasoconstriction or vasodialation

19
Q

how did the heart evolve

A

a muscular tube elongated and bent back against itself and certains regions evolved spatially

20
Q

name how vasodialation can be brought about

A

a tissue that is doing a lot of metabolic work will have high concentrations fo CO2 and therefore decreased pH, which signals for vasodialation and therefore increased blood flow which replensihes oxygen concentration and removes waste products

21
Q

why are respiritory pigments used

A

respiritory gasses need to be transported, and transport in solution is not efficient

22
Q

what is something all respiratory pigments have in common

A

they are metalloproteins (proteins with a metal element)

have more than one subunit and are allosteric
fe
they bind reversibly to oxygen
there is a positive correlation between pO2 and % saturation

23
Q

name some of the adaptions animals thts fly have

A

they ventilate quickly, but this doesnt cause hypocapnia (loss of co2 leafing to vasoconstriction and anoxia)

relatively large hearts comapred to similar sized mammals

small muscle fibres so oxygen diffuses quickly

many capillaries

very good at fat metabolism, which mammals arent

24
Q

unique features to high flyers

A

large lungs to increase surface area for diffusion

more effective breathing pattern

haemoglobin has a higher affinity for oxygen

mitochondria have been redistributed and are close to the capillaries so Atp can be used to increase rate of oxygen diffusion

25
Q

discuss isotonic, hypotonic and hypertonic environments

A

isotonic; ion concentration insode and outside of RBC’s is the same

hypertonic; ion concentration outside RBC’s is higher than inside them; water leaves RBC’s

hypotonic; ionic concentration outside a RBC is lower than inside the RBC; water moves into RBC’s and causes rupture

26
Q

what are 2 general methods of osmoregulating

A

changing the permeability of membranes

actively transporting ions

27
Q

why are rockpools are difficult environment

A

salinity changes as water evaporates and sea water hits etc

28
Q

where can soft and hard water be found

A

soft water; lakes

hard water; rivers

29
Q

what is the primary osmoregulation organ

A

kidney

30
Q

why can the waxy monkey frog and the chiromantis frog survive long periods of time in dry environment

A

they have impeareable skin with a waxy substance on it. it melts when its hot

31
Q

what part of a reptile is impeareable to water loss

A

scales

32
Q

which animal has 90% of its water gain from metabolic water (breakdown of sugars etc)

A

kangaroo rat

33
Q

how do animals have to modify air thats being breathed in order to extract oxygen from it

A

air must be heated up to 38 degrees and water must be added to increase the relative humidity to 100%

34
Q

air that is breathed out has water in it, how do kangaroo rats minimise this water loss

A

their nasal structures have swirled bones that increase the surface area for water extraction via the counter current blood system

35
Q

how do marine vertebrates osmoregulate differently to terrestrial vertebrates

A

reniculate kidney (many small lobes)