4A Flashcards
1
Q
cell wall
A
- provide support
- prevent water loss
- made of cellulose > made from b glucose
- cellulose is straight / long
2
Q
middle lamella
A
- outermost layer of cell
- made of pectin
- calcium pectate > bonding of calcium ions w pectin
- sticks adjacent plant cells together
- gives plant stability
3
Q
plasmodesmata
A
- channels in cell wall that link adjacent cells together
- allow transport of substances + communication between cells
4
Q
Pits
A
- regions of cell wall where wall is very thin
- Arranged in pairs > pit of one cell lined up w pit in adjacent cell
- Allow transport of substances between cells
- Allow water to pass thru xylem vessels
- pit membrane consit of middle lamella + primary wall
5
Q
Permenant vacoule
A
- contains cell sap (water, mineral ions, enzymes) to maintain osmosis
- keep the cell turgid
- tonoplast is the membrane of the vacoule > controls what enters / leaves
6
Q
Chloroplast
A
- surrounded by double membrane > called thylakoid membranes
- stack parts of chloroplast called grana
- grana linked together by lamallae (thin, flat pieces of thylakoid membrane)
- site where photosynthesis takes place
- green pigment (chlorophyll)
7
Q
stroma
A
- thick fluid in chloroplasts
8
Q
Amyloplast
A
- contain starch granules
- storage of starch grains
- conveert starch into glucose for release when required
9
Q
function of stem
A
- Support
- Transport
10
Q
Schlernchyma
A
- provide support > not involved in transport
- made of bundles of dead cells vertically in stem
- hollow lumen + have cell walls
- cells walls thickened w lignin (not pits)
- lots of cellulose
11
Q
xylem
A
- transport water + mineral ions up plant
- provide support
- Transpiration
- hollow lumen (no cytoplasm)
- no end walls
- walls thickened / strengthened w lumen
- substances move in / out of vessels thru pits (no lignin)
12
Q
phloem
A
- translocation
- transport organic solutes (sucrose) > where made to needed
- has sieve tube elements + companian cells
- STE> living cells + joined end to end to form sieve tubes
- sieve has holes which allow solute to pass thru
- CC provide energy for active transport
13
Q
nitrate ions
A
- produce amino acids > proteins
- plant growth
- leaves turn yellow
- plant growth is stunted
14
Q
calcium ions
A
- calcium ions in middle lamella of plant cell wall combine w pectin to make calcium pectate which holds plant together
- permeability of membrane
- growing points die back
- leaves become yellow
15
Q
magnesium ions
A
- needed to produce green pigment ‘chlorophyll’
- activation of plant enzymes + synthesis of nucleic acid
- leaves turn yellow
- growth slows down
