Plant tissues and cells Flashcards
What is cytoplasmic streaming?
flow of contents within a cell caused by currents in the cytoplasm
What types of cells can a proplastid become?
- chromoplast (contains water-insoluble pigments)
- chloroplast (photosynthesis)
- leucoplast (storage)
- etioplast (precursor to chloroplast)
What is the name and colour of the pigments found in chromoplasts?
carotenoids (i.e carotene, xanthophyll) = red/orange/yellow colours
What are three types of leucoplasts?
amyloplasts = starch storage
elaioplasts = lipids
proteinoplasts = proteins
What is the name of the amyloplasts that help plants detect gravity?
statoliths
What functions do vacuoles have?
- maintain turgor pressure
- cell support
- storage (water, toxins, nutrients, water-soluble pigments)
- metabolizes waste
- regulates enzymes, pH and ion activity
What is the name and colour of the pigments found in vacuoles?
anthocyanins (type of flavonoid) = red, purple colours
Name the 4 components of the cell wall and their analogies
cellulose = rope (provides strength and restricts expansion)
hemicellulose = chains (provides extra strength by lining cellulose molecules, can allow for cell expansion when desired)
pectin = jelly (fills in gaps, forms the middle lamella, determines pore size for transport, resists cell compression)
lignin = concrete (adds extra strength and is more permanent)
What non carbohydrate based components are also found in the cell wall?
- lignin (amino acid based, found in SCW, adds strength and rigidity)
- suberin (fatty acid based, found in cork, waterproofs the cell wall)
- cutin (fatty acid based, found in cuticle, prevents internal water loss)
- waxes (fatty acid based, found on exterior surface, prevents water loss, deters insects from climbing onto surfaces, deflects UV light)
Name the 3 types of cell tissues in plants and their components
ground tissue (parenchyma, collenchyma, sclerenchyma)
vascular tissue (xylem, phloem)
dermal tissue (epidermis, periderm)
List the characteristics of parenchyma
- living cells
- thin and even cell walls
- have a primary cell wall (pectin)
- are considered generalized tissue cells
- aid in storage, metabolism and photosynthesis
List the characteristics of collenchyma
- living cells
- thick uneven cell walls
- have a primary cell wall (pectin)
- provides flexible support
List the characteristics of sclerenchyma
- dead cells
- thick even cell walls
- have a secondary cell wall (lignin)
- provides rigid support
What type of sclerenchyma cell causes pears and other fruits to be grainy?
stone cells (have very thick SCWs)
What can the xylem do?
- long distance signalling
- water + dissolved nutrient transport
- physical support
What can the phloem do?
- long distance signalling
- sugar transport
What can the epidermis do?
- mediates gas exchange (guard cells)
- can be pigmented for reproduction
- protection + first line of immune defense
- helps in organ development
- minimize water loss
Name the different components found in xylem tissue
- tracheary elements (tracheids and vessels)
- xylem parenchyma
- xylem fibres (sclerenchyma)
What functions do the different components in xylem have?
tracheary elements [dead] = water transport + physical support
xylem parenchyma [living] = metabolism
xylem fibres [dead] = structural support using lignin (SCW)
Which patterns of secondary cell walls are found in protoxylem and metaxylem?
proto = annular (ring) and spiral
meta = scales, rungs
Do angiosperms and gymnosperms have the same types of tracheary elements?
gymnosperms only have tracheids, angiosperms have both tracheids and various vessels
Name the different components found in phloem
- sieve elements (sieve cells, sieve tube elements)
- phloem parenchyma (albuminous/companion cells)
- storage parenchyma *
- fibres
- sclereids
What is callose?
glucose based temporary component of cell walls surrounding sieve plates
What function do the different components of phloem have?
sieve elements [living] = sugar transport
phloem parenchyma [living] = metabolism
fibres/sclereids [dead] = structural support
