Transport in animals Flashcards
State 5 reasons why animals need specialised transport systems
high metabolism
small SA : V ratio –> large diffusion distances
products ( e.g. hormones, enzymes) made in one area but needed in another
food must be transported to every cell
waste products must be removed
describe how diffusion distance, SA, volume, SA:V ratio vary with increasing organism size
as organism size increases:
- SA:V ratio decreases
- diffusion distance increases
- SA increases but volume increases at a faster rate
how is the level of activity related to needs for oxygen and glucose
increased activity = higher needs for oxygen and glucose
define diffusion
net passive movement of substances from an area of high concentration to low concentration (down a concentration gradient)
define circulatory system
the transport system in an animal
define open circulatory system
a circulatory system with a heart but that doesn’t contain the transport medium (transport medium flows freely)
define closed circulatory system
where the blood is enclosed in blood vessels and doesn’t come into direct contact with cells
define haemolymph
insect blood. it doesn’t carry oxygen or carbon dioxide. it transports food, nitrogenous waste, cells involved in defense
define single circulatory system
the blood travels once through the heart for a complete circulation
eg
heart –> gills , oxygenated –> cells, deoxygenated –> heart
define double circulatory system
2 separate circulation systems:
1) deoxygenated blood is pumped from the body, through the heart and to the lungs
2) oxygenated blood is pumped from the lungs, through the heart and to the body
define pulmonary circulation
the part of the double circulatory system that takes deoxygenated blood to the lungs, oxygenates it and takes it back to the heart
define systematic circulation
the part of the double circulatory system that takes the oxygenated blood around the body, and the deoxygenated blood back to the heart
draw a diagram showing both a single closed circulatory system and a double closed circulatory system
do it now
an example of animals with:
open circulatory system
closed single circulatory system
closed double circulatory system
open circulatory:
insects
closed single:
fish
closed double:
mammals
similarities and differences between open and closed systems
similarities
- mass transport
differences
- haemolymph vs blood
- open vs closed
- in contact with cells vs not
- no o2 or co2 vs carries o2 and co2
advantages and disadvantages of open / closed systems
advantages disadvantages
open less vulnerable to pressure
amount of haemolymph can’t be varied
closed high pressure
amount of blood can be varied
more efficient
similarities and differences between single and double circulatory systems
similarities
closed
blood
differences
through heart once vs twice
low pressure returning to heart vs high pressure
advantages and disadvantages of single and double circulatory systems
advantages disadvantages
single low pressure limits efficiency
double more efficient
copes with higher demand
differences between pulmonary and systemic circulation
pulmonary
- heart to lungs
- oxygenated
- lungs to heart
systemic
- heart to body
- deoxygenated
- body to heart
list the sequence of blood vessel types from the heart
- artery
- arteriole
- capillary
- venule
- vein
state the anatomical layers in arteries veins and capillaries
- state the components of each layer
- state properties and function of each layer
tunica intima
epithelial cells
- smooth, thin lining
tunica media
smooth muscle tissue -
contracts and relaxes to change size of lumen
elastic fibres - elastin
stretch and recoil
tunica externa
collagen - protein
- structural support
- maintains shape
compare proportions of each layer in artery, capillary, vein and state function
width of wall muscle layer elastic layer inner surface valves size of lumen pressure
artery capillary vein
width of wall thick very thin thin
muscle layer thick none thin
elastic layer thick none thin
inner surface folded epithelium// endothelial cells // smooth endothelium
valves no no yes - semi lunar
size of lumen small tiny large
pressure high falling low
structure of capilliaries
function of capillaries and how they’re adapted
wall = single epithelial cell thick lumen = single RBC thick
link arterioles to venules
wide junctions between cells to allow fluid to pass out
explain how structure of veins adapts them to function
explain how valves work
blood pressure is low so semi lunar valves prevent back flow
wide lumen and smooth epithelial cells to allow blood to flow easily
valves open when blood flows towards heart, and close when blood starts to flow backwards
valves in arms and legs are between muscles, so when the contract they force the valves to open.
breathing forces blood in the chest to the heart
these act against gravity
