Gas exchange Flashcards
component 3
how is surface area affected by size?
increasing the size increases surface area
if size is increased what will happen to the volume?
it will increase
what effect does increasing size have on S.A. to volume ratio
SA to volume ratio would decrease
what are specialist exchange surfaces?
body parts that allow for the exchange of materials between the body and the environment.
e.g: lungs, gills, digestive system, and roots.
what are five common characteristics of specialist exchange surfaces?
- Large surface area relative to volume (This increases the rate of diffusion)
- Short diffusion distance (This allows for faster and more efficient exchange of substances)
- Moist surface (This allows gases to dissolve more easily)
- Steep concentration gradient (This is maintained through heavy blood flow)
- permeable
suggest what effect an increas in size might haveon the need for specialist exchange surface in larger organisms
the bigger than animal the smaller the SA to volume ratio, diffusion distances would be to great to rely on diffusio from the bodies surface. an internal gas exchange system would be required
give three example of unicellular or smalll multicellular organisms and their adaption to increase SA to volume ratio
- amoeba: pseudopodia (structures that function as a way of locomotion and to capture + engulf particles.)
- flatworm: very thin and flat
- earthworm: elongated (closed circulatory system)
what is a closed circlatory system
a system where blood is contained within a network of vessels and pumped through the body in a continuous loop
what do terristrial organisms need to survive on land?
to coserve water, therefore organs for gas exchange need to be retained in the body to prevent heat and water loss
give three examples of organisms and thier gas exchange surface
- reptiles:
> reptiles have lungs with an in-out bellow likw arrangement - birds:
> lungs with air sacs attached - amphibians:
>larvae live in water and have gills
>adults use their moist skin as a respiratory surface( exept when active some use lungs)
there are 14
name the components of the lungs
- toung
- epiglottis
- trachea
- oesopagus
- cartilage rings
- lungs (left&right)
- ribs
- intercostal muscles
- bronchi
- bronchioles
- plueural space (contains a small amount of fluid that lubricates the lungs as they move during breathing)
- pleural membranes (protects the lungs and helps them move smoothly when breathing)
- diaphram
- larynx
what are the constituents of a bronchiole
- smooth muscle
- cilited epithelium
- loose tissue with elastic fibre
- goblet cell
- blood vessel
trachea
- cartilage
- smooth muscle and elastic fibires
- ciliated epithilium with goblet cells
- small blood vessel
- mucus secreting gland
what is the function of a goblet cell
secrete mucus to trap mucus, dust & microbes
what is the function of ciliated epithelial cells
to waft mucus up the trachea/bronchi to be swallowed
what is the function of elastic fibres
elastic recoil of alvioli in expiration
what are two advantages of humans having internal exchange surfaces
it reduces water and heat loss
how do you calculate surface area to volume ratio?
divide the surface area by the volume
what is the respiratory system in insects called?
tracheal system
what is the tracheal system
a system of tubes in insects that transport oxygen from the outside environment to the insect’s body
what are the mechanisms of the insect tracheal system
- air sacs
- spiracle
- trachea
- tracheoles
- fluid sacs
during ventilation how does inspiration work in insects
- the thoracicand first two abdominal spiricals open
- the other 6 abdominal spiracles are closed
- the abdomen expands causing an increase in volume and a decrease in pressure
- air flows in
during ventilation in insects how does expiration work
- the thoraic spiricals and first 2 abdominal spiricals close
- the other abdominal spiricals open
- the abdomen contracts causing a decrease in volume and an increase in pressure
- air flows out
what are the advantages of insects closing the spiricales
to reduce water loss
