Chapter 35 Flashcards
tissue
a group of cells consisting of one or more cell types that together perform a specialized function
organ
consists of several types of tissues that together carry out particular functions
True or false:
Plants have tissues composed of different organs which in turn are composed of different cell types
FALSE:
Plants have ORGANS composed of different TISSUES which in turn are composed of different cell types
what are the three basic organs in a plant?
roots, stems, and leaves
plants take up water and minerals from _____ ______
below ground
plants take up CO2 and light from _____ ______
above ground
a. roots rely on photosynthesis in the shoot system for what?
b. shoots rely on root system for what?
water and minerals
what are the two types of angiosperms?
monocots and eudicots (dicots)
what is the root’s three important functions
- anchoring the plant
- absorbing minerals and water
- storing carbohydrates
what is a gymnosperm?
a plant that has seeds unprotected by an ovary or fruit.
what is an angiosperm?
a plant that has flowers and produces seeds enclosed within a carpel.
most eudicots and gymnosperms have what type of system?
taproot system
what does a taproot system consist of (with definitions)
taproot- the main vertical root
lateral roots- or branch roots, that arise from the taproot
most monocots have what types of root system?
fibrous root system
what does the fibrous root system consist of? (with definitions)
Adventitious roots- arise from stems or leaves
lateral roots - arise from the adventitious roots
what does the stem consist of?
alternating system of nodes
nodes
the points at which leaves are attached
internodes
the stem segments between nodes
axillary bud
a structure that has the potential to form a lateral shoot or branch
apical bud (or terminal bud)
located near the shoot tip and causes elongation of a young shoot
apical dominance
helps to maintain dormancy in most axillary buds
what is the leaves main job (usually)
Photosynthesis
what do leaves consist of?
- a flattened blade
2. a stalk called the petiole, which joins the leaf to a node of the stem
veins
the vascular tissue of leaves
what type of veins do monocots have?
what type of veins do eudicots have?
a. parallel veins
b. branching veins
True or False:
In classifying angiosperms , taxonomists may use leaf morphology as a criterion
True
each plant organ has what three tissues?
dermal, vascular, and ground tissues
cuticle
a waxy coating that helps prevent water loss from the epidermis
periderm
protective tissues replace the epidermis in older regions of stems and roots
(the corky outer layer of a plant stem formed in secondary thickening or as a response to injury or infection.)
trichomes
outgrowths of the shoot epidermis and can help with insect defense
the dermal tissue system consist of
the epidermis - the outer layer of cells covering the plant for protection
vascular tissue system
carries out long distance transport of materials between roots and shoots (where your xylem and phloem are)
what are the two vascular tissues?
xylem and phloem
xylem
conveys water and dissolved minerals upward from roots into the shoots
Phloem
transports organic nutrients from where they are made to where they are needed
stele
the vascular tissue of a stem or root is collectively called the stele
in angiosperms what does the stele look like?
it is a solid central vascular cylinder
the stele of stems and leaves is divided into what three things?
- Vascular bundles
- strand of xylem
- phloem
ground tissue system
where photosynthesis occurs
-have a lot of cells with chloroplasts
pith
ground tissue internal to the vascular tissue
cortex
ground issue external to the vascular tissue
the cells in ground tissue is specialized for what three things?
- storage
- photosynthesis
- support
what are the 5 major types of plant cells
- parenchyma
- collenchyma
- sclerenchyma
- water-conducting cells of the xylem
- sugar-conducting cells of the phloem
Mature parenchyma cells have what 5 characterisitics?
- have thing and flexible primary walls
- lack secondary walls
- are the least specialized
- perform the most metabolic functions
- retain the ability to divide and differentiate
collenchyma cells
grouped in strands and help support young parts of the plant shoot (living cells which elongate as the stem and leaves)
what are the 4 characteristics of collenchyma cells
- They have thicker and uneven cell walls
- they lack secondary walls
- these cells provide flexible support without restraining growth
- can stretch and support any part of plant that is growing
sclerenchyma cells
function as support (ex: coat of a seed)
what are the 2 things to know about sclerenchyma cells?
- are rigid because of thick secondary walls strengthened with lignin
- they are dead at functional maturity
what are the 2 types of sclerenchyma cells?
- Sclereids- short and irregular in shape and have thick lignified secondary walls
- fibers- long and slender and arranged in threads
what are the two types of water conducting cells?
- tracheids - (dead at maturity) found in the xylem of all vascular plants
- vessel elements- (dead at maturity) align end to end to form long micropipes vessel elements are common to most angiosperms and a few gymnosperms
sieve tube elements
alive at functional maturity, though they lack organelles
sugar conducting cells
sieve plates
the porous end walls that allow fluid to flow between cells along the sieve tube
* these are on the side of the phloem*
true or false:
each sieve-tube element has a companion cell
true
indeterminate growth
a plant growing throughout its life
determinate growth
when plant organs cease to grow at a certain size
meristems
perpetually embryonic tissue and allow for indeterminate growth
apical meristems
located at the tips of roots and shoots and at the axillary buds of shoots
primary growth
when apical meristems elongate shoots and roots
lateral meristems
is arranged parallel to the sides of an organ and that is responsible for increase in diameter of the organ
secondary growth
the process in which thickness is added to woody plants
vascular cambium
adds layers of vascular tissue called secondary xylem (wood) and secondary phloem
cork cambium
replaces the epidermis with periderm which is thicker and tougher
what are the two types of later meristems
- vascular cambium
2. cork cambium
meristems give rise to what two things
- initials (also called stem cells) which remain in the meristem
- derivatives - which become specialized in mature tissues
true or false:
in woody plants, primary growth and secondary growth occur simultaneously but in different locations
true
annuals complete their life cycles in what time period?
one year or less
biennials complete their life cycle in what time period?
require two growing seasons
perennials complete their life cycle in what time period?
live for many years
primary growth produces what parts?
the root and the shoot systems produced by apical meristems
the root tip is covered by a root cap which does what?
protects the apical meristem as the root pushes through soil
growth occurs just behind the root tip in three zones of cells which are
- zone of cell division
- zone of elongation
- zone of differentiation, or maturation
the primary growth of roots produces what three things
- epidermis
- ground tissue
- vascular tissue
what is the stele like in angiosperm roots?
it is a vascular cylinder
what does the stele (vascular cylinder) look like in most eudicots
it is starlike in appearance with phloem between the “arms”
what does the stele (vascular cylinder) look like in most monocots?
a core of parenchyma cells is surrounded by rings of xylem then phloem
cortex
region between the vascular cylinder and epidermis
what fills the cortex?
the ground tissues (which is mostly parenchyma cells)
endodermis
- innermost layer of the cortex
- regulates passage of substances from the soil into the vascular cylinder
what do lateral shoots develop from?
axillary buds on the stem’s surface
what does the inside of stems look like in eudicots?
the vascular tissue consists of bundles arranged in a ring
what does the inside of stems look like in monocots?
the vascular bundles are scattered throughout the ground tissue, rather than forming a ring
stomata
allow CO2 and O2 to exchange between the air and the photosynthetic cells in a leaf
guard cells
- two guard cells flank each stomatal pore
- regulate its opening and closing
mesophyll
- the ground tissue in a leaf
- sandwiched between the upper and lower epidermis
what are the two layers of mesophyll?
- the palisade mesophyll- in upper part of leaf
2. spongy mesophyl- in the lower part of the leaf; loos arrangement allows for gas exchange
Things to know:
- vascular tissue of each leaf is continuous with the vascular tissue of the stem
- veins are the leaf’s vascular bundles and function as the leaf’s skeleton
- each vein in a leaf is enclosed by a protective bundle sheath
where does secondary growth occur and rarely occur?
- occurs in stems and roots
2. rarely occurs in leaves
secondary growth is characteristics of _____ and many _____
gymnosperms and many eudicots
**but not monocots
the secondary plant body consists of the tissues produced by the ______ and ______
- vascular cambium
2. cork cambium
vascular cambium
add secondary xylem to the inside and secondary phloem to the outside of the cylinder of meristematic cells (cells are perenchyma cells)
what does the xylem and phloem do in a tree to make the tree wider?
- the older xylem is more towards the center of the tree while the new xylem is towards the edge so the old ones accumulate to make a wider tree trunk
- the older phloem sloughs off (or goes away) and does not accumulate
lenticels
in the periderm allow for gas exchange between living stem or root cells and the outside air
bark
consists of all the tissues external to the vascular cambium, including secondary phloem and periderm
