Test 2 Flashcards
Arid (name)
Xerophytes
dry climate
Wet environment (name)
Hydrophytes
Aquatic leaves
submerged in water
deeply lobed- effeciently take in CO2 and H2O
less xylem- dont need to transport water
large air spaces in mesophyll
Xerophytes
Smaller leaves= surfaces area to volume ratio or reduced to spines or no leaves thicker leaves thicker cuticle fewer stomata lots of hairs-pubescent parallel to suns rays
all help to reduce water loss
Hydrophytes
deeply lobed larger leaves thin leaves thinner cuticle more stomata=even on upper surface air spaces (for flotation)
root function
anchor plants
absorb water and minerals
store water and food
other specialized funciton
four regions of the root
region of maturation
region of elongation
apical meristem (region of cell division)
root cap
types of roots
tap root
branch root
adventitious roots
Dicot Root
Steele is 1/8 size (small) primary xylem in cross or star shape endodermis pericycle passage cells no pith
Monocot root
Steele is 1/2 size (big) primary xylem in ring around steele epidermis= U shaped cells pith pericycle
soil composition
organic matter
minerals
living organisms
soil texture
sand to silt to clay
soil structure
clumps and pores
water in soils
hygroscopic
gravitational
capillary
hygroscopic
chemically bound to soil particles
unavailable to plants
gravitational
drains out of pore spaces
capillary water
held in by pore adhesion (against gravity)
available to plants
influenced by soil structure and organic content
pH in soil
alkalinity- Cu, Fe, Mg less available
acidity- inhibits growth of nitrogen fixing bacteria
high precipitation or over-irrigation can cause bases to leech from soil
soil organisms influence pH
aerial roots
corn, coleus
tap root
one primary root
with secondary roots develop off of
develops from radicle
usually dicots
Carnivorous plants (conditions)
low nitrogen environments
need nutrients through lure and catch prey
digest them to get amino acids and proteins
Carnivorous plants types
passive pitfall
active flypaper
active steel trap
active mouse trap
passive pitfall
PITCHER PLANTS insect lands on lip and falls into plant hair points down into plant and insect cannot get back out nectar rim and water attract insects waxy surface enzymes in water break down insects
Active flypaper
SUNDEW and BUTTERWORT hairs exude nectar and attract insects plant responds to touch of hairs leaf curls around insect can distinguish between protein and no protein-- insect and other plant
Active steel trap
VENUS FLYTRAP
two sides with hinge and forms a cage
snaps shut
hairs inside lips snap shut– very quick response
triggers in changes in leaves
decrease in day length
decrease in light intensity– hormonal changes
decrease in temperature
decrease in water
Specialized roots
food storage water storage propagative pneumatophores aerial contractile buttress parasitic Flying Walruses Pet Pandas And Carry Blue Paint
Food storage roots
enlarged to store starch and other carbohydrates
extra cambial cells in xylem of roots that produce lots of parenchyma cells and cause organ to swell
sweet potatoes, yams, carrots, radishes
water storage roots
some in pumpkin family and especially in plants that live in arid environments
water in roots used when supply in soil is inadequate
propagative roots
adventitious buds along roots near surface of ground
buds in aerial stems=suckers
suckers can be separtaed form plant and grown independently
reproduciton of plant and continuation of survival
cherries, apples, pears,
pneumatophores roots
specially spongy roots that extend above waters surface and enhance gas exchange between atmosphere and the subsurface roots
swamp plants
aerial roots
root formed above the ground prop roots of corn-support adventitious roots of ivies photosynthetic roots of orchids mangroves= collect debris to create more soil
contractile roots
roots that pull plant deeper into the soil
bulbs=lily, dandelion(leave coming out of the ground
buttress roots
roots in shallow soil that produce huge roots toward base of trunk
great stability
look like part of the trunk
parasitic roots
no cholorphyll and dependent on chlorophyll-bearing plants
parasitize their host plants vias peglike projections called haustoria
they develope along stem in contact with host
dodders, broomrapes, pinedrops
fibrous roots system
large numbers of fine roots of similar diameter
then develops from adventitious roots
monocots
adventitious roots
those that do not develop from another root but develop instead from a stem or leaf
root cap
parenchyma protection perception of gravity amyloplasts= gravity sensors in dicots- slimy substance/ lubricant= bacterial growth (nitrogen)
Region of cell division
apical meristem 1. protoderm 2.ground meristem-cortex 3. procambuim= primary xylem and phloem pith in stems but not dicot roots
Region of Elongation
large vacuoles
cells get longer and wider
add girth through secondary tissues via the cambium
last layer of cell growth/size/shape change
region of maturation
cell maturation/differentiation
root-hair zone
root hairs
develop from epidermal cells absorb water and minerals adhere to soil particles increase surface area hairlike/delicate
steele
vascular cylinder precambuim primary xylem primary phloem pith in monocots
casparian strips
suberin bands
perpendicular to roots suface
prevent water from passing through the otherwise permeable cell walls
forces water and dissolved substances going adn leaving the core to pass through the plasma membranes
regulates types of minerals absorbed and transported by root to stems and leaves
in endodermis
passage cells
thin-walled
retain casparian strips
mycorrhizae
fungus roots
essential to normal growth and development
help plant absorb phosphorus
form mantle of millions of threadlike strands that facilitate the absorption of water and nutrients
plant gives fungi sugars and amino acids
forms mycorrhizal sheath- hyphae
root nodules
legume family (fabacae) a small swelling associated with nitrogen-fixing bacteria that invade roots produce enzymes with which they can convert nitrogen into nitrates and other nitrogenous substances readily absorbed by roots
living organism on soil composition
add to content through wastes
alter soil through activity
compact soil-loose soil
produce carbon dioxide-> combined with water-> acid-> increase rate at which minerals dissolved
loams
best agricultural soil mix of sand silt and organic matter 40% silt 40% sand 20% clay light soil granular soils with pore spaces that are 40-60% of total volume of soil clay-spaces too small=not enough air sand-too large water drains out=too much air=lose of nitrogen
green
chlorophyll
red
anthocyanins
yellow
carotenoids
orange
red and yellow together
brown
chlorophyll and anthocyanins
aka tannins
Leaf color change process
stop chlorophyll production
once chlorophyll decreases- reveals underlying carotenoid pigments
anthocyanin production increases
once chlorophyll decreases- reveals underlying carotenoid pigments
carotenoid always there jsut not seen
yellow remains constant from year to year
Anthocyanins (and betacyanins) production increases in some species
red/purples
varies from year to year
weather dependent- warm sunny day, cool nights
lots of sun-lots of photosynthesis -> sugars into anthocyanins
Temp and weather= wet warm spring+pleasant summer=bright colors
late spring/severe summer drought= delayed colors
some trees cant produce anthocyanins
leaf abcission- hormonal changes
changing daylight/water
cell differentiation-two layers
protective layer
separation layer
protective layer
protects where leaves fall save water cells become coated and filled with suberin (waterproof) barrier against bacteria and fungi seals off leaf scar
separation layer
cell differentiation cells become large cells become gelatinous -weakened -less strong -pectin break down eventually only held on by xylem eventually breaks off in wind
monocot vascular bundles
scattered thorughout cell
contain:
phloem= companion cells, seive tube members,
xylem=air space
Dicot vascular bundles
ring around outside of cell
cortex tissue
collenchyma
parenchyma
vascular cambium tissue
meristemic tissue
divide and produce secondary tissues that add to girth
secondary xylem and phloem
pith tissue
parenchyma
pith rays
separate individual vascular bundles
extensions of the pith
primary growth
apical growth
tips/adds length
secondary growth
lateral growth
adds girth/width
bundle cap tissue
fibers
functions of stems
support= cortex, collenchyma, sclerenchyma
water/nutrient transportation and storage
protection=thorns
reproduction
anchoring
heartwood
center of tree trunk inner wood typically darker resins. gums, tanins, pigments in xylem dead and getting older
sapwood
outerwood
living
functional xylem
lighter in color
annual rings
alternating growth of summer and winter growth
spring and summer wood
seasonal changes
spring wood
grows rapidly
larger vessel elements
more spongy
often lighter in color
summer wood
water stress=grows slower
smaller vessel elements
dense appearance
darker color
secondary xylem in wood
lots of cellulose
lignin
tougher and rot resistant
pine tree age
count whorls
bark
everything outside of the vascular cambium
includes phloem (inner bark)
cark cambium == periderm/outer bark
cork
rhizome
stem
what tissue does the lateral root develop from
the pericycle== still has some meristemic tissues in it
cortex
mostly food storage
contains endodermis= prevents water from passing through via casparian strips
monocots vs dicots
mono=pith, xylem around pith(bundles), large steele, exodermis
dicot= no pith, no exodermis, xylem forms star.cross, endodermis=casparian strip, small stele
mesophyll
dicot parenchyma chlroenchyma-- chloroplasts palisade-top-greatest # of chloroplasts, protection and photosynthesis spongy-bottom, gas exchange-- air spaces
monocot leaf
corn
buliform cells-loose water=curling, in upper epidermis
mesophyll undifferentiated
bundle sheath and sheath extension
astrosclerid
in mesophyll
star shaped cells
in xerophytes
stomatal crypts
keep moisture from evaporating
humid antichmaber like SE
conserve h2o
rhizome
horizontal stems below ground scalelike leaves adventitious roots along the stem (mainly lower surface) irises grasses/ferns ginger
runners
horizontal stems above ground
long internodes
strawberries
adventitous buds
stolons
beneath surface like runners but grow in diff directions
tubers
potatoes
at tips of stolons
swell from accumulation of food
bulbs
large buds surrounded by numerous fleshy leaves
small stem at lower end
adeventitious roots grow from bottom
onions
corm
liek bulbs but almost entirely stem tissue
adventitious roots at base
gladiolus
cladophylls
flattened stems
prckly pear cactus
scalelike leaves with axillary buds in center
what makes conifers softwood
xylem=trachids
no fiber or vessel elements
veins
xylem and phloem surrounded by thicker-walled parenchyma cells called a bundle sheath
give leaf its skeleton
phloem function
transport sugars
active transport
xylem function
transport water through osmosis and diffusion
spines
modified leaves
cacti
prickles
outgrowths from epidermis or cortex
rose
raspberry
thorns
modified stems
grape
tendrils
modified leaves
help plant in climbing or support
curled around other objects
conifers
thick cuticle sunken stomata antifreeze in cell sap resin in resin ducts resin leaks out and protects wound traps bacteria and fungi
why water
dissolved minerals and nutrients chemical reactions photosynthesis mesuphyll moist to take in co2 turgor pressure=stiffness imbibition begins germination(process of absorbing H2O) high heat capacity-temp regulation
forces that move water
diffusion osmosis capillarity hydrostatic pressure gravity
cappilarity
water attracted to water
water hanging from finger
water attracted to other molecules
hydrostatic pressure
water pressure
water baloon= fill with water and press against sides
gravity
working against upward movement
working with sugar transport downwar
imbibition
swelling of tissues due to water absorption
turgor pressure
pressure with in cell resulting from water uptake
cells get stiff
opposite=flaccid
potatoes in salt water example
opening and closing of stomata in regards to water transpiration
linked to osmotic pressure
a. By opening or closing the stomata
i. All linked to osmotic pressure
ii. Depends on turgor pressure in the guard cells
b. Cells are full of water = high turgor pressure
i. Pressure against cell wall
1. Cells are stiff and elongated
2. Cell walls against stoma are thicker because outer guard cell can stretch and side against stoma cant stretch
a. Like putting tapa on a balloon
3. Stretchy side will stretch and bend and grow longer instead of wider
4. Inside walls dont stretch
5. Bowed cells that form an open stoma
water transpiration regulated by
light dark CO2 increase water loss gutation of water
light
- potassium and chloride ions enter guard cells
1. As hydrogen is pumped out
2. Higher K and Cl concentration inside cells == lower water concentration
a. Osmosis of water into cells
i. Stretches cells and open stoma
3. More light=more photosynthesis=more co2 and o2 out
dark
stomata close
Co2 increase
close stomata
- Because you lose water at same time
a. Close when you don’t need to have them open
loss of water
close stomata
- Transpiration rate (water loss) influenced by
a. Humidity
i. Evaporation happens rapidly on dry days
b. Temperature
i. Evap rapidly on hot day
c. Air currents
i. Evap rapid on windy day
Guttation water
- Leaking of water from tips of leaves during night
2. Doesn’t evaporate
sink
storage where sugar is located
roots, stem, other non-photosynthetic tissue
mineral requirements
a. Carbon, hydrogen, oxygen
b. Macronutrients = taken up by roots
i. Nitrogen= proteins, nucleic acids, chlorophyll
ii. Phosphorus= respiration, cell division, ATP
iii. potassium= activates enzymes,
iv. calcium= middle lamella, moves substances across plasma membranes
v. magnesium= part of chlorophyll
vi. sulfur= part of some amino acids
c. vitamins= produced by the plant
i. most act as co-enzymes
1. many are electron receptors
hormones
i. chemical signals
ii. bind to cellular receptors
1. series of reactions
2. results in
a. activation/inactivation of enzymes
b. change of function
c. gene transcription
i. protein synthesis
auxins
promote growth by increasing cell length
delay fruit and root abscission
delays fruit ripening
can apply to cut stems= lateral root development, adventitious roots, uniform flowering, kill dandilions
gibberellions
- stimulate growth of stems
2. cell division and increase cell length
cytokinins
- promotes cell division
- esp. when auxins are present
- prolong life of cut flowers and vegetables in storage
abscisic acid
- in fruits= prevents seeds from germinating while still on the plant
- inhibits other hormones
a. inhibit growth
ethylene gas
- promotes fruit ripening
- promotes leaf abscission
- production of ethylene influenced by
a. bruising or cutting of fruit
b. ethylene produces ethylene
i. positive feedback
c. auxins = increase ethylene
d. stop ethylene by taking away O2
applicaiton of ethylene gas
warehouses pump O2 into air to replace N2
wrap in tissue paper to hold gas close to fruit
spread bananas out to slow ripenimg
hormonal interactions
apical dominance
senescence
apical dominance
- growth at tips of plant (length) is dominant over growth of width of branch
- tip grows more rapidly that side branches
- suppression of growth of lateral buds by auxin like inhibitors produced in terminal bud
- at same time there tends to be a deficiency of cytokinins in lateral buds
- cut off apical meristems to stimuli increased development of lateral braches
senescence
- breakdown of cell components in cell membranes
- cell death
- abscisic acid and ethylene
a. promote senescence - nitrogen deficiency or drought speeds up process
- auxins and gibberellins and cytokinins
a. delay senescence
patterns of growth
determinate growth
interdeterinate growth
determinate growth
i. defined limits
ii. predictable pattern=then stops growing
iii. usually stops after fruiting
indeterminate growth
i. no defined limits
ii. keeps growing until something in environment stops it
graminoids
grasses, sages, and rushes
tropisms
perminant movements toward or away from a stimulus
phototropism
gravitropism
thigmotropism= hitting a solid object
turgor movements
changes in internal water pressures and usually iniatiated by contact with objects outside of the plant
sensitive plant
bladderwort
redwood sorrel
taxis
type of movement that involves either the entire plants or its reproductive cell
not amoung flowering plants
cell propeled by flagella or cilia moves towards or away from a source of stimulus
requires mobility
photoperiodism
the initiation of flowering in response to relative lengths of day and night
dormancy
a period of growth inactivity even when the temperature, water, or day length would typically cause plant growth
preparing for winter– cherries, peaches= stone fruits
quiescence
state in which a seed cannot germinate unless environmental conditions nrmally required for growth are present
