Unit 2 Flashcards
Nucleus
the structure that stores DNA in a eukaryotic cell
Nucleolus
the region in a prokaryotic cell that consists of DNA
Ribosome
protein making structure
Rough endoplasmic reticulum
assists ribosomes in making proteins
Smooth endoplasmic reticulum
structure that produces lipids, phospholipids, and steroids
Golgi apparatus
transports molecules throughout the cell
chloroplast
performs photosynthesis in a plant cell
thylakoids
turns light energy into ATP and NADH
grana
the coin-looking things in a thylakoid
mitochondria
produces ATP in a cell
central vacuole
stores water and vitamins in a plant cell
primary cell wall
outermost cell wall in a vascular plant
secondary cell wall
innermost cell wall in a vascular plant
middle lamella
separates primary walls of adjacent cells
plasmodesmata
holes between cells in the cell wall; tunnels allowing movement between cells
meristem
region of cells capable of division and growth in plants
parenchyma
-most common differentiated cell type
-thin primary walls, usually no secondary cells
-changes shape to fill in gaps
-roots made of parenchyma
-performs photosynthesis, storage, secretion
collenchyma
-provides flexible support
-allows plants to bend but not snap
-young structures
-as plants get older, they deposit lignin into these cells
-thick primary walls, usually no secondary wall
sclerenchyma
-thick secondary walls
-lignified
-dead at maturity
-vascular tissue still runs through lignified tissue
-fibers & sclerids
lignin
chemical that makes wood
fibers
sclerenchyma
sclerids
sclerenchyma
simple tissues
-made from only one cell type
-ground tissue
complex tissues
-made from more than one cell type
-dermal tissue, vascular tissue
ground tissue
storage & support (most of cell made up of this)
dermal tissue
outermost protective parts
-epidermis
vascular tissues
conduction (water and sugars)
xylem
-transports water & minerals
-roots –> leaves
-vessel element, tracheid
tracheids
long, thin, and tapered (xylem)
vessel elements
short and wide, have pits, move water faster (xylem)
pits
allow flow of water and nutrients from one vessel element to the next
conduction
transmission of water and minerals
phloem
transports nutrients/sugars/food
sieve-tubes
food conducting members connected by sieve plate
companion cells
control sieve tubes
stele
primary vascular system of the plant axis and its associated ground tissues
microphylls
leaves w a single trace of vascular tissue
megaphylls
leaves with multiple traces of vascular tissue
homospory
1 bisexual spore
heterospory
1 male spore, 1 female spore
megaspore
female spore
microspore
male spore
sporocyte
a diploid cell that divides by meiosis to produce four haploid spores
microsporangium
produces microspores
microgametophyte
produces sperm
megasporangium
produces megaspores
megagametophyte
produces eggs
sori
cluster of sporangium
annulus
spring loads sporangium; springs open when it’s time to release spores quickly
indusium
covers sori; falls off when it’s time to release the spores
rhizome
anchors gametophyte
frond
fern leaf
pinnae
leaflet (fern)
rachis
main stem (fern)
fiddlehead
fern thing that unfolds into frond
prothallus
fern gametophyte
synangium
a 3-lobed sorus made up of sporangia variously united or cohered into a compound structure
tepetum
a layer of nutritive cells that invests the sporogenous tissue in the sporangium of vascular plants
strobili
reproductive structure which contains homosporous sporangia
microstrobili
simple; microsporophylls (scales) are attached to a central axis and have two microsporangia on their lower surface
megastrobili
female strobili; complex; have a seed-scale complex attached to the central axis attached to the central axis
microsporophyll
a leaf on which the microspores are formed
seed-scale complex
made up of only the two prophylls of the axillary shoot of the bract; has two ovules and a sterile bract consisting of fused megasporophylls
bract
Modified, usually small, leaflike structure often positioned beneath a flower or inflorescence
megasporophyll
a leaf on which the megaspores are formed
nucellus
megasporangium surrounded by integuments
integuments
skin-like protective structure around seeds
pollination
the act of getting the pollen to the female
-female produces fluid to allow the pollen to stick
-pollen is brought through the micropyle to the megasporangium
micropyle
a small opening in the surface of an ovule, through which the pollen tube penetrates, often visible as a small pore in the ripe seed
prothallial cells
cells with no function in a pollen grain that differentiate
microsporocyte
initiate meiosis to create 4 microspores
microspore mother cell
microsporocyte
tube cell
single cell in pollen grain that makes pollen tube
generative cell
single cell in pollen grain that makes two sperm
pollen
microgametophyte with 4 cells
megasporocyte
divides by meiosis to create 4 haploid megaspores
megaspore mother cell
megasporocyte
pollen tube
delivers sperm cells to the female gametophyte for double fertilization
polyembryony
multiple embryos are produced, but only one is supported by the plant
seed coat
protective layer that comes from the integuments
monoecious
having both the male and female reproductive organs in the same individual
dioecious
having the male and female reproductive organs in separate individuals
Phylum Lycopoiophyta
-homosporous example: Lycopodina sp.
-heterosporous example: Selaginella sp.
-microphylls
-has sporophylls
Class Psilotopsida
-Phylum Monilophyta
-Psilotum sp. = whisk ferns
-enation: supports sporangia (called synangium)
-has synangium
-homosporous
Class Equisetopsida
-Phylum Monilophyta
-Equisetum sp. = horsetails
-sends stalks underground and pops up new plants all over a garden
-have silica in their cell walls
-homosporous
Class Polypodiposida
-Phylum Monilophyta
-true ferns
-corkscrew thing grows off fferns
-can be edible, poisonous, or halucinogenic
-fiddlehead & frond; cercinate vernation = unrolling of fiddlehead into frond
Phylum Cycadophyta
-cycads
-one of the most ancient phyla of gymnosperms
-has cercinate vernation
-has strobili
-dioecious
-only gymnosperm to have flagellated sperm
Phylum Ginkgophyta
-ginkgos (maidenhair tree)
-only 1 species
-may only be domesticated now
-dioecious
-deciduous
Genus Ephedra
-Phylum Gnetophyta
-used to speed up heartbeet for diet & workout pills and is used to make meth
-most angiosperm-like
-Mormon tea
-Asian
Genus Welwitschia
-phylum Gnetophyta
-Southwest African
Genus Gnetum
-phylum Gnetophyta
-tropics
-looks similar to flowering plants
Phylum Coniferphyta
-pines, cypress, juniper, redwood
evolution of seed plants
-the megasporangium no longer release spores, they are retained (protects spores from drying out)
-reduction in the number of megasporocytes in the megasporangium to one
-survival of only 1 of the 4 megaspores to one
-endosporic development of the gametophyte
-spores growing into gametophytes, fertilization, and initial development of the new sporophyte all takes place in the parent sporophyte
-all are heterosporous
Gymnosperm life cycle step one
strobili
Gymnosperm life cycle step two
microgametogenesis: pollen production
Gymnosperm life cycle step three
pollination - the act of getting pollen to the female
Gymnosperm life cycle step four
megagametogenesis - egg production
Gymnosperm life cycle step five
fertilization - two sperm take 15 months to race through the pollen tube; the first sperm that gets there fertilizes the egg and the second die
Gymnosperm life cycle step six
seed production (1. embryo: product of fertilization, 2. food reserve: comes from megagametophyte tissue, 3. seed coat: protective layer that comes from integuments)
fasicles
a bundle of vascular tissue
peduncle
stem of flower
pedicle
stem of an inflorescence
inflorescence
collection of flowers on one stalk
receptacle
base of the flower, where all parts attach
sepal
protect flower when closed
calyx
collection of sepals
petal
“showy” parts, used for attraction
corolla
collection of petals
parianth
petals and sepals (corolla and calyx, more generally)
androecium
male parts
stamen
include anthers and filaments
-number of stamens varies per plant
anther
produces pollen
filament
supports anthers
gynoecium
female parts of a flower
pistil
ovary that is not chambered
carpel
ovary that is chambered
ovary
produces eggs
ovule
organ that forms the seeds of flowering plants
stigma
sticky tip where pollen is recieved
style
the hollow tube connecting stigma to ovaries
complete flower
flowers that consist of all of the available sterile parts
perfect flower
bisexual flower
bisexual flower
flowers that have both male and female parts
incomplete flower
flowers that are missing some sterile parts
unisexual flower
flower that only has male or female parts
imperfect flower
unisexual flower
superior ovary
ovary that attaches above receptacle
inferior ovary
ovary that attaches inside receptacle
actinomorphic
radially symmetrical
zygomorphic
bilaterally symmetrical
pollen sac
microsporangia
intine
inner mostly cellulose wall of pollen grains
extine
outer wall of pollen grain made of a protein called sporopollenin, which gives each pollen (by species) a unique shape
sporopollenin
a protein that makes up the extine, which gives each type of pollen a unique shape
antipodal end
end of ovary farthest from micropyle
mycropylar end
end of ovary closest to micropyle
polar nuclei
Two nuclei that migrate to the center of the embryo sac and fuse with a male nucleus (sperm) to form the primary endosperm nucleus which divides and sometimes forms the endosperm
synergid
two specialized cells that lie adjacent to the egg cell in the female gametophyte of angiosperms and play an essential role in pollen tube guidance and function
triploid endosperm
a tissue produced inside the seeds of most of the flowering plants following double fertilization
self-pollination
a flower pollinates itself
cross-pollination
a flower pollinates another flower of the same species
seed coat
develops from integuments
monocot
a flowering plant with an embryo that bears a single cotyledon (seed leaf). Monocotyledons constitute the smaller of the two great divisions of flowering plants, and typically have elongated stalkless leaves with parallel veins
eudicot
An angiosperm having two cotyledons in the seed, leaves with a network of veins radiating from a central main vein, flower parts in multiples of four or five
imbibition
the absorption of one substance by another, in particular the uptake of water by a plant or seed
radicle
the part of a plant embryo that develops into the primary root
plumule
the rudimentary shoot or stem of an embryo plant
cotyledon
an embryonic leaf in seed-bearing plants, one or more of which are the first leaves to appear from a germinating seed.
scutellum
a modified cotyledon in the embryo of a grass seed
pericarp
3-layered structure of plant ovaries
exocarp
outer layer of pericarp
mesocarp
middle layer of pericarp
endocarp
inner layer of pericarp
simple fruit
develops from a pistil or a fusion of carpels
aggregate fruit
type of complex fruit; develops from a single flower with nay carpels
multiple fruit
develops from a carpel of many flowers in an inflorescence
dehiscent
splits along a suture(s) at maturity
indehiscent
does not split along a suture(s) at maturity
suture
A line of fusion (e.g., the valves of the carpels of an ovary) or a line of dehiscence (e.g., the lines along which anthers or fruits open)
dry fruit
has a hard pericarp
fleshy fruit
has a soft pericarp
