last lesson of plants allhumdullilah

monocots

one cotyledon, vascular tissue in ring, veins usually parallel to eachother, flowers are in multiples of three, no presence of wood, usually fibrous

dicots

two cotyledons, vascular tissue in star shape, veins are palmate/pinnate, flowers in multiples of 4/5, presence of wood, usually taproot

two transportation processes in plants

• carbs and sugars made in leaves by photosynthesis are carried to other living cells by dissolving in water and going up and down from cells in phloem

• water and dissolved nutrients are taken from roots and transported up to cells in leaves by cells in xylem

how do particles move

concentration gradients

diffusion

high pressure to low pressure

osmosis

diffusion of water thru membrane

diffusion and osmosis requirements

not energy

diffusion of larger molecules (sugar and minerals)

active transport

transport in xylem path

soil + osmosis → roots → root cells → xylem → stem → tissue

transpiration

loss of water when 90% of water that reaches leaf is lost in stomata

how water reaches leaves against gravity

root pressure and transpiration pull

root pressure

exerts positive pressure on water, pushing it upward

root pressure process

Active transport of minerals → Water enters by osmosis → Positive pressure forms → Water is pushed upward with help from adhesion

transpiration pull

negative pressure from top of plant due to cohesion of water

transpiration process

Transpiration creates a pull from the top, and cohesion and adhesion work together to keep the water column intact as it’s drawn up through the xylem

transport in phloem

translocation

translocation

transport of sucrose and others organic molecules thru phloem of plant

pressure flow model

hypothesis that uses osmosis and pressure dynamics to explain how materials are pushed from a source to a sink thru translocation

source

where sugar is made

sink

where sugar is used or stored