plant structure Flashcards
What is the name of cellular structure?
Cytology
what does the plasmodesmata do?
Connections between cells, allow the exchange of hormones
What is the tissue structure called?
Histology
organ
collection of tissues that together carry out a particular function
eg. Root, stem and leaf
what’s the structure of the whole plant called?
anatomy
anatomy
organisation tissues and organs inside organism
what is the structure of the whole plant?
morphology
morphology
outward appearance (shape, structure)
What is the vegetation structure called?
ecology
Homology
when traits in different species exist as a result of an inherited genetic feature
If plants are exposed to the same selective pressures will they share morphological features?
yes
analogous trait
similarities between organisms not present in a common ancestor
Examples of analogous trait ?
spikes to protect from herbivores .
no leaf surface area to reduce water loss, stem for photosynthesis
plasticity
the ability of an individual plant to adjust structure to local environment.
eg. effect wind (mechanical stress), exposed , control
Heterophylly
All cells are genetically identical
are plants mobile?
no they are sessile
Are animals sessile?
no they are mobile
Tissue
group of cells with common structure and function
what the dermal tissue comprised of?
single layer, epidermis
what is the vascular tissue comprised of?
Xylem, phloem
what is the ground tissue comprised of?
parenchyma
what is the meristematic tissue comprised of?
ambryonic cells
totipotent
all cells can de-differentiate, divide and develop into complete new organism
Are animals or plants totipotent ?
plants
Unipotent cell
can develop in just one type of tissue
pluripotent cell
can develop into different tissues but not a whole organism
example of a modified leaf?
onion, spine and tendril
what makes up the epidermis ?
waxy cuticle, stomata, trichomes
what are trichomes?
hairs
what is the mesophyll ?
the middle of the leaf
What is the vascular system made up of?
phloem, xylem, the bundle sheath
What does the phloem do?
transports sugars from the leaves to roots
what does xylem do?
transports water from roots to leaves
what is the bundle sheath?
a protective circle of cells
What do stems do?
carry leaves and position them in the light, control stem length-strategy, connection root to the leaf
Examples of modified stems?
Phylloclade- photosynthetic stem
rhizome- horizontal underground stem
stem tuber- swollen stem
What is the stem made up of?
Apex- bud with meristem, node and internode, and axillary buds
What are axillary buds ?
Side buds. dormant ,ready to grow but dont grow.
why are axillary buds dormant?
The apex releases a hormone that stops the axillary buds from growing. this is so plants do not waste energy and can grow as tall as possible
what are the different fibres in a stem ?
collenchyma and sclerenchyma
collenchyma
in young tissue - living and flexible
sclerenchyma
in mature tissue- dead and rigid
function of roots
Anchor, uptake water and minerals, storage, photosynthesis
Lateral roots
from main root
adventitious roots
roots from stem
root hair
extensions of epidermal cell- increased uptake surface
lateral root
multicellular root
where is vascular tissue located in the roots ?
the centre of root
phloem outside , xylem inside
endodermis
inner layer cortex, controls nutrient uptake
pericycle
can become meristematic, forms lateral root
