Transpiration, Translocation + Photosynthesis Flashcards
upper epidermis
thin and transparent to allow light through
palisade mesophyll
regular shaped cells packed with chloroplasts allows maximum absorption of light for photosynthesis
spongy mesophyll
irregular shaped cells to increase surface area for gas exchange . carbon dioxide exchanged with oxygen
guard cells
control opening and closing of stomata
stomata
allows gas exchange with environment
waxy cuticle
waxy layer prevents loss of water through evaporation
lower epidermis
cells swell to open stomata
xylem cells in leaf
carries water + minerals into cell
phloem cells in leaf
carries sugars out of leaf
petals
reproduction (1)
attracts pollinators
pollinated flowers produce fruit / seeds as the product of sexual reproduction
leaves
contain chlorophyll for photosynthesis
stem
provides plant support , transport of water and minerals through vessels
roots
anchorage of plants, storage of sugar, absorbs water and mineral ions from soil
meristem
area which undifferentiated cells are produced (stem cells)
shoot apical meristem
occurs at tip of shoot, produces new leaves + flowers
lateral meristem
occurs at cabium, produces girth and thickness in stem
root apical meristem
occurs at tip of root controls root growth and development
location of xylem + phloem in leaf
phloem found near lower surface, xylem above
location of xylem + phloem in stem
vascular bundles on edge of stem, phloem further out
location of xylem + phloem in roots
vascular bundles inside root
transpiration stream
the flow of water through a plant , from the roots to the leaves, via the xylem vessels (water will eventually be lost by evaporation through the stomata)
transpiration
the loss of water from leaves by evaporation through stomata
How do mineral ions enter root hair cell (and why does it effect transpiration)
Active transport, it lowers water potential in the root hair cell
what happens after the water has left the root hair cell (where does it reach)
it moves from cell to cell via osmosis until it reaches the xylem in the root center
what happens in the xylem (transpiration) to water
water moves via capillary action, driven by evaporation of water in leaf (water removed at top)
what happens to water once it leaves xylem
moves through leaf cells via osmosis
how does water exit the plant
through stomata if guard cells are open, or used by leaf in photosynthesis
why is transpiration stream useful for plants
-minimal energy requirement
-distributes mineral ions
-water needed in leaf for photosynthesis
-ensures turgidity around all of plant
why cant plants absorb water through their leaves
it clogs their stomata
how are rainforests plants adapted to overcome stomata clog
shaped differently to allow water to run onto ground(pointed tips)
translocation
transportation of sucrose (and amino acids ) up and down the plant
source + sink spring (growth period) of sucrose
source - storage organs (eg roots)
sink - growing areas (new shoots, stems)
summer source + sink
source - photosynthesizing leaves
sink - roots for storage of excess sucrose
winter source + sink
source - storage organs
sink - other parts of respiration
where + how are sugars made in a plant
made in the leaf cell by photosynthesis
how does sucrose move from source cell to companion cell
active transport
how does sucrose move from companion cell to phloem
diffusion
a high conc of sugar at the top of the phloem causes..
water to enter the phloem vessel by osmosis
how does the translocation of sugars occur
movement of water into phloem vessel sends sucrose to sink cell - the root
what happens to sucrose in the sink cell
it is stored as starch
photosynthesis
how plants convert light energy (from the sun) into chemical energy (food/glucose). this happens inside chloroplasts in the leaf
formula for photosynthesis chemical equation
6CO2 + 6H2O → C6H12O6 + 6O2
adaptations for photosynthesis of leaf
large surface area
stomata
thin
chlorophyll
network of veins
how does large surface area help photosynthesis
more area for photosynthesis to occur
how does stomata help for photosynthesis
controls movement of CO2 and O2
how does a leaf being thin help photosynthesis
short diffusion path for CO2 to diffuse into leaf cells
how does chlorophyll help photosynthesis
absorbs sunlight to transfer energy into chemicals
how does a network of vein help a leaf for photosynthesis
supports leaf and transports water and carbohydrates
limiting factors
something that prevents the rate of photosynthesis
name 4 limiting factors
light
CO2 conc
temperature
chlorophyll conc
investigation of light and its affect on photosynthesis RQP - IV DV AND CV
IV - distance of lamp
DV - rate of bubbles of gas
CV - temp of water
pattern of results in RQP rate of photosynthesis light
further the distance the less bubbles are produced
uses of glucose in a plant
energy during aerobic respiration
to make proteins for growth and repair
to make cellulose for a cell wall
storage of starch
storage of fats and oil
how can a greenhouse optimize photosynthesis
parafin heater (adds CO2)
light bulbs
optimal light
pros of greenhouse
-increases yield
-growth independent of season
-conditions easily altered
-monitoring can be done remotely
cons of greenhouse
-expensive to build
-expensive to run
-large area of land required
-less jobs provided
-lack of variation in dna of plants leads to crops easily being lost to disease
nitrate deficiency symptoms
poor growth, yellow leaves
phosphate deficiency symptons
poor root growth , discolored leaves
potassium deficiency symptons
poor growth of fruit and flowers , discolored leaves
magnesium deficiency symptons
yellow leaves
