Ch. 35 Plant Structure & Growth Flashcards
big idea: plant tissues, cells, organs, as well as how they form. know the difference between monocots and eudicots in terms of structure (& finding good microscope pics of each can help)
what are the three basic organs of vascular plants? [reproductive organs not included]
roots, stems, and leaves
what tissue types are roots composed of?
dermal tissue only
what tissue types are stems and leaves composed of?
ground tissue
what are the five main plant cells and what tissues do they form?
- parenchyma = dermal / ground
- collenchyma = ground
- sclerenchyma = ground
- xylem = vascular
- phloem = vascular
what is the function of roots?
-plant anchorage
-water / nutrient absorption & storage
what are root hairs & what are their function?
-small tips on the end of roots
-function in extending surface area for absorption
what is the structure of plant stems? what are apical & axillary buds?
-alternating system of nodes & internodes
-apical buds = lengthen the plant
axillary buds = widen the plant [branches]
what is the function of a plant stem?
-support
-transporting water/minerals up and photosynthetic product around plant
what is the structure of leaves?
leaves = flattened BLADE + PETIOLE [leaf stalk]
what are the functions of plant leaves?
- photosynthesis
- attracting pollinators
- support/storage/asexual reproduction
how do monocot and eudicot leaves differ?
monocot = parallel veins, few petioles
eudicot = branching veins
what are the 2 main types of plant reproductive structures & what is their function?
- flowers = attract pollinators
- fruits = protect & disperse seeds
what are the three types of plant tissue?
dermal, ground, and vascular
where is dermal tissue found?
-on the outermost layer of all parts of a plant
what is the function of dermal tissue?
-protection & water conservation
what is the structure of dermal tissue? [name the four main components]
- epidermis = outermost, single layer of parenchyma cells
- waxy cuticle = prevents water loss
- periderm = epidermis in woody plants
- trichomes = epidermal variations, lots of functions
where is vascular tissue located?
-roots & shoots
what is the function of vascular tissue? [what do xylem and phloem do?]
xylem = carries water/minerals from roots to shoots
phloem = carries sugary sap from source to sink
what is the structure of vascular tissue?
stele = xylem + phloem = vascular cylinder/bundle
how is the stele arranged in roots, shoots, and stems?
roots = stele is arranged in a cylinder
shoots = stele is arranged in many veins
stems = stele is arranged in bundles
where is ground tissue located?
at the cortex = external to vascular tissue
at the pith = internal to vascular tissue
what is the function of ground tissue?
photosynthesis / storage / support
what is the structure of ground tissue? [what cells make it up?]
consists of parenchyma, sclerenchyma, and collenchyma cells
what is the function of parenchyma cells?
-does most metabolic functions: photosynthesis and storage. can divide into specialized cells if needed
what is the structure of collenchyma cells?
unevenly thick primary wall, think a large oval with a smaller oval in the corner
what is the structure of parenchyma cells?
-these cells have a thin, flexible cell wall with a large central vacuole [think a thin box with a circle in the middle]
what is the function of collenchyma cells?
provides flexible support for growing structures - shoots and leaves
what is the structure of sclerenchyma cells?
-thick cell walls, dead at maturity. think a giant circle that is entirely cell wall
what is the function of sclerenchyma cells?
-support
-provides hardness of nuts [sclereids] and fibers [hemp/flax]
what is the structure of xylem?
-elongated tube, dead cell
-has narrow tubes called tracheids
-has wider, short tubes called vessel elements
what is the structure of phloem?
-hollow tube cells [alive] with sieve plates inbetween cells
-companion cells connected by plasmodesmata
what is determinate and indeterminate growth in plants?
determinate = has a fixed height, will not go past it
indeterminate = keeps growing throughout its life
what are meristematic cells?
-the “stem cell” of plants, can continuously divide and create “derivative cells” that can differentiate into specialized cells
what is the function of apical meristems? where is the meristem located?
apical meristem = primary growth, lengthening [taller] of shoots and roots
-located at apical buds, axillary buds, root tips
what is the function of lateral meristems? where is the meristem located?
lateral meristems = secondary growth, widening in diameter
-meristem located in roots/shoots/branches
what type of growth is vascular cambium responsible for?
secondary xylem / pholem
what type of growth is cork cambium responsible for?
-dermal tissue / periderm
-primary and secondary growth occur simultaneously
how do roots grow? [where does it occur?]
-root growth occurs at the root tip
-root contains apical meristem = stem cell divides, making a derivative
what is the zone of elongation?
zone where cells grow larger, pushing the root down and making the plant longer
what is the zone of differentiation?
zone where cells develop into specialized roles, contains root hairs
what occurs in primary growth of shoots?
-leaf primordia are crowded together, become separated as internode cells elongate
-growth occurs due to elongation after cell division
-lateral branches arise from axillary buds
what is the function of stomata? where are they located on a leaf?
-located most abundantly on the bottom of leaves
-function in controlling the movement of water/O2 out of the leaf and CO2 into it
-opening is regulated by guard cells
what is the secondary plant body composed of?
tissues made by vascular cambium and cork cambium
what are the two layers of cambium in the lateral meristem?
-cork cambium & vascular cambium
what is vascular cambium?
-single layer of meristematic cells
-develops from the primary vascular bundle
-cells divide to form secondary xylem [wood] on the inside and secondary phloem on the outside
what is early wood?
xylem produced in the spring. has larger cell diameter with thinner walls
what is late wood?
xylem produced in the fall. has smaller cell diameter with thicker walls & darker wood
what is heartwood?
secondary xylem no longer used for transport
what is sapwood?
wood formed between heartwood and the bark, containing functioning vascular tissue
what is cork and what is its function?
cork = outermost periderm
-functions in protection
what is bark and what is bark composed of?
bark = all tissues outside vascular cambium
-bark = cork + cork cambium + secondary phloem
