Ch 10 Plants Flashcards
Bryophytes
primitive plants that lack vascular tissue. live in moist environments because no roots or xylem, tiny. EX: moss
traecheophytes
have transport vessels, xylem and phloem, separated into ancient seedless (ferns, spore reproducing) and modern seed plants (can be further divided into gymnosperms and angiosperms)
gymnosperms
conifers, cone bearing plants. needle shaped leaves, thick cuticle, and stomates in stomatal crypts enable minimal water loss. EX: cedar, sequoia, redwoods, pines, yew
angiosperms
flowering plants. most diverse. further separated into monocotyledons and dicotyledons
Characteristics of monocots
one cotyledon, scattered vascular bundles, parallel leaf veins, flowers in 3’s, fibrous roots
characteristics of dicots
two cotyledons, vascular bundles in ring, netlike leaf veins, flowers in 4’s or 5’s, taproots
examples of monocots
grasses, wheat, palm trees, corn, oat, rice. provide most of the food for world
examples of dicots
daisies, roses, carrots, and most flowery plants.
modifications so plants can live on land?
cell walls made of cellulose, roots and hairs, stomata, cutin
stomata
open to exchange photosynthetic gases and close to minimize water loss
cutin
waxy coating on leaves, prevents water loss
meristem tissue
continually dividing into new cells until plant dies, unlike animals
primary growth of plants
vertical, elongation down into soil and up into air, new cells come from dividing growth layer called APICAL MERISTEM.
apical meristem
zone of cell division, located at buds of shoots and tips of roots.
three zones of plants cells at different stages of primary growth
zone of cell division, zone of elongation, and zone of differentiation. at the very end is root cap
zone of cell division
contains meristem cells actively dividing,
zone of elongation
cells elongate and push the root cap downward deeper into soil
zone of differentiation
cells undergo specialization into three meristems
Secondary growth
lateral growth, increase in girth. New cells provided by lateral meristem. responsible in enlargement of trunks.
function of roots
anchor plant, absorb nutrients from soil, and store food.
difference between structure of monocot and dicot roots
dicots have plus sign in middle, monocots have empty pith in middle
epidermis of root
covers entire surface and is modified for absorption.
root hairs
slender cytoplasmic projections fom epidermal cells, increase roots absorption surface area
cortex of plants
function is storage, consists of parenchyma cells that have plastids that store starch
stele
vascular cylinder, xylem and phloem, surrounded by pericycle
endoderm of plants
each endoderm is wrapped with Casparian Strip, function is to select which minerals enter vascular cylinder and body of plant
casparian strip
continuous band of waxy material that is impervious to water and dissolved materials. wraps endoderm.
symplast
continuous system of cytoplasm of cells interconnected by plasmodesmata
apoplast
network of cell walls and intercellular spaces within plant body that permits extensive extracellular movement of water in plant
mychorrhizae
in regions where roots lack root hairs, these supply plant with water and mineals. symbiotic structures
rhizobium
symbiotic bacteria that lives on legume roots. they fix nitrogen from air into usable for by root.
taproots
single large root that gives rise to lateral branch roots. in many dicots. some tap into deep soil water, others are for storage.
adventitious roots, and EX
roots that rise above ground; aerial roots like mangroves or other trees in swamps. prop roots like corn that support plant
difference between stem of monocot and dicot
dicot has vascular bundles in ring. monocot has bundles scattered
pith
parenchymal tissue cells midified for storage
function of epidermis
protection
function of waxy cuticle
minimize water loss
function of guard cells
control opening of stomates
function of palisade mesophyll thats tightly packed
photosynthesis
function of palisade mesophyll thats loosely packed
photosynthesis and diffusion and exchange of gases
function of veins in plants
carry water and nutrients from soil to leaves and carry sugar.
stomates
enable gas exhange between spongy mesophyll and air when opened.
why dont plants always keep stomata open for gas exchange
they would lose a lot of water through transpiration. so at day when photosynthesis is running top speed, stomata are open, at night they clse
when guard cells become turgid…
they curve and open the stomata.
three types of plant tissue
dermal, vascular, and ground
dermal tissue
outer protective covering of plants. protected by cuticle. no chloroplasts, cant photosynthesize EXCEPT for guard cells.
vascular tissue
transports water and nutrients up and down. xylem and phloem.
xylem consists of
tracheids and vessel elements
phloem consists of
sieve tube elements and companion cells
ground tissue
makes up rest of plant tissue besides vascular and dermal. consists of parenchyma, collenchyma, and sclerenchyma
parenchyma cells
in ground tissue, they are the typical looking plant cell. have only primary cell wall. suppport the plant when turgid. contain mesophyll cells
collenchyma cells
have unevenly thickened primary cells walls, still no secondary cell waslls. strings of celery
scelerenchyma cells
thick primary and secondary cells walls, fortified with lignin. pure support
tracheids
elongated cell in xylem that have secondary walls hardedned with lignin.
Xylem is what makes up stuff we call ____
wood
how much energy does xylem use to pull up water against gravity
none
what phenomenon help xylem pull up water against gravity
transpirational pull and cohesion tension
transpirational pull-cohesion theory
for each molecule of water that evaporates from leaf by transpiration, another molecule of water is drawn in at the root to replace it
factors that affect rate of transpiration
high humidity slows it down, wind reduces humidity which increases rate, higher light intensity increases rate of transp, closing stomata stops transp
phloem
carry sugar from photosynthetic leaves to rest of plant via transloccation.
like the xylem, transportation in the phloem requires no energy
false
sugar in plants is stored in the ____
roots
vegetative propagation
asexual plant reproduction. piece of vegetative part of plant produces identical plant to parent
petals
brightly colored modified leaves. foundin circle of sepals, attract animals that will pollinate
sepals
outermost circle of leaves, green, enclose bud before it opens and protects flower before it opens
pistils/carpels
female part of flower, each consist of ovary, stigma, and style
ovary
swollen part of pistil, contains ovule
ovule
in ovary, the ova (female gametophytes) are produced by meiosis
style
long, thin stalk of pistil
stigma
sticky top of style, where pollen lands and germinates
stamen
male part of flower; anther and filament
anther
where sperm (pollen) is produced by meiosis
filament
threadlike structure that supports anther
whats inside a pollen grain
three haploid nuclei: one tube nucleus, two sperm nuclei.
what happens to the two sperm in a pollen grain when inside ovary
one fertilizes the egg and becomes an embryo (2n), the other fertilizes two polar bodies and becomes the endosperm (3n) - provides food for embryo
seed
the ovule becomes a seed after fertilization
what happens to ovary after fertilization
becomes ripened and turns to fruit.
seed consists of ____, _____, and _____
seed coat, embryo, and cotyledon/endosperm
the plant embryo consists of ____, _____, and ______
hypocotyl, epicotyl, and radicle
hypocotyl
becomes lower part of stem and roots
epicotyl
becomes upper part of stem
radicle
embryonic root, first organ to emerge
alternation of generations
sexual life cycle where n and 2n generations alternate. gametophyte (n) produces gametes, which fertilize and develop into sporophytes (2n) that produces haploid spores by meiosis which forms gametophyte.
antheridium
structure that produces sperm, develops on gametophyte
archegonium
structure that produces eggs, develops on gametophyte
gametophyte (plant)
haploid adult plant
megaspores
produced by large female cones and will develop into female gametophytes
microspores
produced by small male cones and will develop into male gametophytes (pollen grains)
protonema
branching filaments produced by germination moss spores, becomes gametophyte in moss
sporangia
located on tip on mature sporophyte, where meiosis occurs, produces haploid spores
sporophyte
diploid adult plant
sori
raised spots in underside of sporophyte ferns, clusters of sporangia
the _____ generation dominates the life cycle of a moss
gametophyte; moss spends most of time as gametophyte and sporophytes depends on it for nutrients
In ferns, the _____ generation is larger, and is independent from the ________.
sporophyte; gametophyte
In angiosperm seed plants, the _____ generation is totally dependent on the _____ generation.
gametophyte; sporophyte
auxins
plant hormones that cause tropisms. enhance apical dominance (upwards)
cytokininss
plant hormones that stimulate cytokinesis and cell division. . delay aging by inhibiting protein breakdown.
gibberellins
promote stem and leaf elongation
abscisic acid
plant hormone that inhibits growth and promotes seed dormancy to withstand drought.
ethylene
plant hormone thats a gas. promotes ripening. “one bad apple spoils the whole barrel”
