Lecture 4 -- Plants

Question 1

what is the cell wall made from

Answer 1

the cell membrane

Question 2

what are the main polysaccharides holding the fibrils together

Answer 2

pectin, hemicellulose, and microfibril

Question 3

when is the secondary cell wall made

Answer 3

after the primary cell wall

Question 4

what is the outermost wall

Answer 4

the primary cell wall

Question 5

dermal

Answer 5

outermost layer - single layer

Question 6

vascular

Answer 6

moves fluid around

Question 7

ground

Answer 7

all of the other stuff

Question 8

epidermal cells

Answer 8

form single layer on outside of plants – always outermost unless woody.
waterproofs cell – cuticle waxy covering involved in waterproofing

Question 9

most general type of ground tissue is

Answer 9

parenchyma cells.

Question 10

parenchyma cells

Answer 10

type of ground tissue, takes care of metabolic processes (photosynthesis, storage), lacks secondary cell wall - mostly. and differentiates at maturity.

Question 11

examples of parenchyma cells

Answer 11

fruit flesh, endosperm, pith + cortex

Question 12

collenchyma cells

Answer 12

provide support / stiff, supports especially young and growing organs, unevenly thick primary cell wall, NO secondary wall, ALWAYS JUST BELOW EPIDERMIS, type of ground tissue

Question 13

examples of collenchyma cells

Answer 13

rib of celery.

Question 14

Sclerenchyma cells

Answer 14

‘scelere’ means hard. has thick secondary cell wall with lignin, does not continue to divide once mature, supports, protection of tissues no longer elongating, cannot elongate at maturity, 2 forms fibres, and scliereids.

Question 15

fibres examples

Answer 15

hemp, burap,

Question 16

scliereids examples

Answer 16

pear – what makes it gritty.

Question 17

water-conducting cells of XYLEM

Answer 17

tracheids and vessel elements, make up vascular tissue, move water upward from soil to plant, support and supply of water and minerals, dead at maturity (when doing their thing they are dead) secondary wall is lignified, often spiral, and tracheas and vessels differ in shape

Question 18

tracheids shape

Answer 18

narrow, tapered, pits allow water flow

Question 19

vessels shape

Answer 19

wider, like soup cans stacked on top of each other.

Question 20

programmed cell death 3 steps

Answer 20

becomes trashed :
1. cytoplasm moving,
2. secondary cell wall formed,
3. death (vacuole implodes)

Question 21

lignin

Answer 21

2nd most abundant natural polymer NOT polysaccharide, fills spaces and bonds cellulose, hemicellulose, and pectin, occurs in anything that SEEMS woody, (palm trees, bamboo)

Question 22

sugar conducing cells of phloem:

Answer 22

sleeve tube elements. type of vascular tissue, transports sugars, hormones, and some minerals, alive at maturity, with companion cell (parenchyma)

Question 23

plants grow from WHAT

Answer 23

meristems

Question 24

what are meristems

Answer 24

they remain, and can divide forever, ultimate source of all parts of mature sporophyte, undifferentiated.

Question 25

locations and types of meristems

Answer 25

Apical meristems (AM) - root and shoot, primary growth. Lateral meristems -- occurs in truly woody plants, vascular cambium, and cork cambium , secondary growth.

Question 26

what does secondary growth mean for woody plants

Answer 26

growth in diameter and production of the wood.

Question 27

shoot apical meristem (SAM)

Answer 27

all other cells come from the SAM : lead primordial, young leaf, ...

Question 28

the 3 tissue systems and where they come from

Answer 28

dermal, vascular, ground all come from the same apical meristem

Question 29

Apical meristem

Answer 29

source of primary growth of both shoot and root. makes three other meristems

Question 30

what three other meristems are made from apical meristem

Answer 30

protoderm -- turns into epidermis (dermal tissue) procambium -- turns into vascular tissue ground meristem -- turns into ground tissue

Question 31

view of the shoot draw and label

Answer 31

should have a peak where SAM is, next to it a leaf, outer part is labeled protoderm, then from leaf to other "shoot" little dashed lines which are the pro cambium, the a little axillary bud between other "shoot" and SAM, and everything else inside is the ground meristem.

Question 32

shoot structure and development, draw cross sections of young shoots for eudicot and monocot.

Answer 32

circle for each, vascular bundles in ring in eudicot, and bundles scattered for monocot. epidermis outer layer for both, inside material is ground tissue for both, xylem on inside, phloem on outside of vascular bundle,

Question 33

root apical meristems make three meristems as well, draw and label root,

Answer 33

upside-down U with cap, cap is called cap, right under cap, little collection of cells, that is the root apical meristem (RAM), then a tube like figure called the vascular cylinder/stele, the outer layer of that is the pro cambium, the very outer layer of whole thing is protoderm, everything else inside is ground meristem, near cap is zone of cell division, in middle is zone of elongation, and at bottom is zone of maturation.

Question 34

what occurs in zone of maturation

Answer 34

root hairs form

Question 35

what is the cap

Answer 35

a collection of dead cells

Question 36

root hairs

Answer 36

single epidermal cells, increase the surface area, they emerge from the part of plant that has stopped moving.`

Question 37

young root, eudicot and monocot draw and label

Answer 37

EUDICOT: circle -- outer layer is the epidermis,, another small circle within-- outer layer of that is the endodermis, area between large and small circle -- cortex (ground tissue), stuff inside small circle -- phloem, right after small circle -- pericycle, x shape within small circle is -- xylem MONOCOT: circle -- outermost layer is epidermis, small circle outermost layer -- endodermis, area between both circles is -- cortex (ground tissue), area within small circle is -- pith (ground tissue), scattered vascular bundles within small circle, -- pointing inside is xylem and pointing outside is phloem.

Question 38

what is everything is the endodermis called in the roots

Answer 38

called stele

Question 39

young roots characteristics

Answer 39

endodermis is innermost layer of cortex, stele or vascular cylinder is. all cells inside endodermis; arise from pro cambium

Question 40

lateral root

Answer 40

originates in pericycle (outermost layer of vascular cylinder), grows out through context and epidermis

Question 41

SUMMARY of structure of primary non-woody roots | root cap, root hairs, endodermis, vascular cylinfer

Answer 41

root cap -- protects root hairs -- epidermal cells, increase absorption area endodermis -- innermost layer of cortex, surrounds vascular cylinder vascular cylinder -- centre of root; contains vascular tissues xylem and phloem, and some ground issue