Flashcards in Lecture 4 Deck (66):
something that should, or does contain one seed
reproductive structure of conifers?
reproductive structure of flowering plants?
microgametophyte in conifers?
nourishing embryo in conifers?
microgametophyte in flowering plants?
nourishing embryo in flowering plants?
how many cells are the conifers megagametophyte?
how many cells are flowering plants megagametophyte?
8 nuclei, 7 cells
what is special about conifers seeds?
they are naked
Parts of the shoot system?
nodes, branch, auxiliary bud, leaf, internode region
Place on shoot where leaves emerge, sometimes branches
originally bud, that can remain dormant until it wants to grow
contains blade and petiole
space on shoot between nodes
what does the root system consist of?
adjacent, parallel cellulose molecules (polysaccharide), rope-like
thin, in all cells; all plants have (except sperm and sea plants)
primary plant cell wall
thicker, only in some cells; some plants (helps with strength)
secondary plant cell wall
what are plant cell walls mostly composed of?
some functions of plant cell walls?
Determines and maintains cell shape as plant cell (and membrane with it) within cell wall can expand and contract
Provides support, mechanical strength: allowing plants to get tall, compete for light, hold out thin leaves
Prevent membrane from bursting, because cells will continue swelling w/o cell wall
Control rate and direction of cell grow
Form shape of plant, determines how plant can grow
Physical barrier to threats like:
water in suberized (waxy) cells, some cell walls aren't waxy
**Remember wall is porous and allows passage of small molecules***
Carb storage, which the cell can take back and use
What are the three types of polyssacharide in cell walls?
cross-linking glycans (hemicellulose)
What does hemicellulose/ cross linking glycans do?
bond with cellulose
what is the function of pectin in the cell wall?
holding everything together like glue
: material of pectic substances which holds adjacent cells together by acting like a glue
Was the secondary or primary cell wall made second?
the secondary cell wall was made second
How was the secondary cell wall made?
the membrane inside the cell makes the cell walls
primary pushed outwards
why are there two cell walls
the connections between the cells. Extensions between cells where membrane is continuous
Outermost coating of all land plants (single sheet/layer)
function of epidermal cells
protection from bacteria
wax and epidermal cells make the ____
function of the cuticle
cell type: Functions, usually performed as a unit of these cells (accomplish things in groups), general cell
function of parenchymal cells
do parenchymal cells have a secondary cell wall?
When do parenchymal cells divide?
Support, especially of young and growing organs
- uneven primary cell wall
do collenchymal cells have a secondary cell wall?
are collenchymal cells alive at maturity? what do they do at maturity?
yes; they elongate at maturity
Support, protection of tissues no longer elongating/ getting longer because they are hard cells with thick secondary wall that has polymer lignin in it.
- has 2 forms
are sclerechyma cells alive at maturity? can they elongate at maturity?
probably dead at maturity; cannot elongate at maturity
do sclerenchyma cells have a secondary wall?
yes, a thick secondary wall
what are the two types of sclerenchyma cells?
water conducting cells of xylem?
tracheids and vessel elements
_____ have tracheids?
all vascular plants
____ have vessel elements
are xylem cells alive at maturity?
What is special about xylem cells second wall?
it is lignified; woody
how does water flow through xylem cells
tracheids: through the pits
vessel elements: through tops and bottoms
openings in cell walls between cells
order of programmed cell death/apotosis
1) Cytoplasmic streaming
2) Secondary cell wall formed
3) Vacuole implodes
sugar conducting cells of the phloem?
are sieve elements alive at maturity?
what are special about sieve elements?
they have companion cells
Ultimate source of all parts of mature sporophyte (organs, ect)
Retain "forever" the ability to divide (similar to stem cells)
Roots AM and shoot AM
Primary growth of plant tissue systems
Vascular cambium and cork cambium
what do lateral meristems enable the plant to become?
What are the three intermediate meristems?
what does the procambium make?
what does the protoderm make?
what does the ground meristem make?