Efficient transport and exchange - SB8 Flashcards
What do all chemical reactions in the body produce - what must be done to it, why?
waste must be excreted to not cause problems
What do kidneys remove, why is it dangerous and how is it produced?
urea- poisonous - produced by break down of amino acids
What do the lungs get rid of? how is it produced?
carbon dioxide is produced in aerobic respiration
What are different substances the body brings in? why?
oxygen and glucose, food molecules / mineral ions - all produce new substances for the body
What type of transport do many substances of the body use to travel?
diffusion
How are surfaces in the body adapted for diffusion? explain why these adaptations help
thin - so particles dont have far to diffuse
large surface area - more room for partciles to diffuse
Why do multicelluar organisms have their own transport systems?
it would take too long for materials to diffuse from outside cells to inside
what do capilaries use to transport substances to and from cells, why?
blood - more efficient
what is true about a cell with a large surface area?
the more a substance can diffuse into /out in a certain time
what happens if the cells volume is too large?
the cell cannot fill up with the materials it needs quick enough
what is the equation for surface area to volume ratio?
surface area/ volume
in terms of surface area: volume ratios, what do larger cells produce? why?
smaller ratios - the smaller the ratio, the less surface area an object has per unit volume
what is true about organs regarding surface area - volume ratios?
they have large ratios
What is the first step to gas exchange in the alveoli?
Air moves into alveoli
What is the second step to gas exchange in the alveoli?
blood flows round the alveoli in capilaries flowing continuously to maintain the concentration gradient, full of CO2
