biology module 3 transport in plants

what is the need for transport systems

to take co2 and nutrients in and to release waste products

how are single celled organisms able to exchange substances directly with the environment

due to their large sa:v ratio. and the diffusion distance is small so essential nutrients can reach the necessary parts of the cell efficiently

why do smaller organisms have smaller metabolic demands

they have lower levels of activity

why do larger organisms require specialised mass transport systems

increasing transport distances, sa:v ratio, and increasing levels of activity

what does every cell in a plant require

water, glucose, and mineral ions

what happens to the sa:v of an organism as the size increases

the sa:v decreases because volume increases much more rapidly than surface area

how is having a high sa:v ratio help single celled organisms

it allows for the exchange of surfaces to occur via simple distillation

how does a large surface area benefit organisms

allows for max absorption of nutrients and gases and secretion of waste products

how does a small volume benefit organisms

the diffusion distance is shorter

what are some adaptations of plants to increase sa:v ratio

plants have a branching body shape, leaves are flat and thin, roots have root hairs

why do larger organisms have a higher level in metabolic activity

they contain more cells than smaller organisms

what is mass flow

the bulk movement of materials

is diffusion involved in mass transport systems

some diffusion involved but only at specific exchange sites

what do mass transport systems help do

bring substances quickly from the exchange site to another maintain diffusion gradients at exchange sites, ensure effective cell activity by keeping the immediate fluid environment of cells within a suitable metabolic range

what is the xylem

transport water and mineral ions

what is the phloem

transport sucrose

functions of the xylem

vascular tissue that carries dissolved minerals and water up the plant, structural support, food support

where is the vascular bundle found in the roots

the centre

where is the vascular bundle found in the stems

on the outside

where is the vascular bundle found in the leaves

form the midrib and veins and spread from the centre in a parallel line

function of the phloem

transports organic compounds from the leaves to the roots, tra