Lecture 1-Plant Parts

Question 1

what is plant cell box made of

Answer 1

cellulose and hemicellulose

Question 2

How are plant cells glued together?

Answer 2

Pectin

Question 3

Plasmodesmata

Answer 3

connects plant cells, allows materials to move between living cells

Question 4

Symplast

Answer 4

interconnected network of living cells

Question 5

Apoplast

Answer 5

interconnected network of dead cells

Question 6

Acetabularia

Answer 6

algae made of just one cell

Question 7

Advantage of multicellularity

Answer 7

Great complexity in form

Question 8

3 Types of Simple Tissue

Answer 8

parenchyma, collenchyma, sclerenchyma

Question 9

Parenchyma Tissue

Answer 9

very common in plants, isodiametric shape

Functions: storage, photo, secretion, reserve for wounds

Question 10

Aerenchyma

Answer 10

specialized parenchyma, aeration of roots in water

Question 11

Collenchyma Tissue

Answer 11

not generally common

Question 12

Sclerenchyma Tissue

Answer 12

common, various shapes. Fibres and Sclereids

Question 13

Fibres

Answer 13

cell length 1-10cm (ramie, Boehmeria 1/2m)
in all organs.
linen, rope, clothing, bioplastics

Question 14

Sclereids

Answer 14

defense. stone cells. asterosclereids (water lily stem)

abrasives, walnut shell grit

Question 15

2 Types of Complex tissues

Answer 15

xylem, phloem

Question 16

Xylem

Answer 16

dead cells: water roots to leaves
Living: hormones top to bottom
parenchyma, sclerenchyma and tracheary elements (dead)

Question 17

2 Tracheary Elements

Answer 17

tracheids and vessel elements

Question 18

Tracheids

Answer 18

water-conducting, secondary cell walls, more common than v.e, bordered pits for strength, cells interdigitate

Question 19

Vessel elements

Answer 19

only in angiosperms, water conduction, convergent evo. open-ended cells connected by performation plate

Question 20

Parenchyma cells in xylem

Answer 20

transports hormone indole-3-acetic acid (auxin), which controls development (inhibits branching)
resin ducts (defence)

Question 21

Sclerenchyma in xylem

Answer 21

structural. fibres, sclereids

Question 22

Phloem

Answer 22

mostly alive
dead cells: support/defense
living: transport of organic cmpds, hormone transport bottom to top (cytokinins that regulate cell division)
sieve elements, parenchyma, sclerenchyma

Question 23

Sieve elements

Answer 23

sieve tube members-missing a nucleus but alive

paired w/ protein-rich cell (companion cell) that transfers materials in/out of phloem

Question 24

Parenchyma cells in phloem

Answer 24

loads/unloads organic compounds and minerals
specialize parenchyma-transfer cells
resin ducts (defense)

Question 25

Sclerenchyma cells in phloem

Answer 25

fibres, sclereids

Question 26

Functions of Phloem tissue

Answer 26

transport of organic cmpds (passive)
offloading cmpnds to storage cells (active)
transport of plant hormone (cytokinin)
defense (phloem parenchyma prevents microbes)

Question 27

Three tissue systems

Answer 27

dermal tissue, ground tissue, vascular tissue

Question 28

Dermal tissue

Answer 28

epidermis, always on outside

Question 29

Ground tissue

Answer 29

parenchyma, sclerenchyma, collenchyma (simple tissues)
stem: cortex and pith
root: cortex and pith (not always pith)
Leaf: mesophyll and palisade tissue

Question 30

Vascular tissue

Answer 30

xylem and phloem (complex tissues)

root: in middle, no need for mech. support
shoot: towards edges-better mech. support
leaf: netowrk of veins in middle of leaf

Question 31

Shoot apical meristem

Answer 31

gives rise to tissue systems

Question 32

Root zones

Answer 32

zone of division, zone of elongation, zone of differentiation

Question 33

X-section order of tissues from outside in

Answer 33

epidermis-cortex (mostly parenchyma tissue, innermost layer is endodermis)-vascular tissue (xylem in middle, phloem between arms of xylem, endodermis in circle around bundle)

Question 34

endodermis

Answer 34

living cylinder of cells that acts as barrier to apoplastic fluids