exam 2 (lect 12,13)

Question 1

body plan of dicot seedling

Answer 1

shoot apical meristem (hypocotyl, root)

2 cotyledon

Question 2

meristem

Answer 2

region of undifferentiated tissue where concentration of cell div occur

Question 3

primary growth

Answer 3

extension of plant body (root or shoot) and form of primary issues (dermal, vasc, ground tissues)
arise from apical meristems
linear growth

Question 4

secondary growth

Answer 4

thickening of root and stem
lateral growth
arise from lateral (secondary) meristerms

Question 5

func of roots

Answer 5

anchorage, water absorption, nutrient absorption (limiting to growth), interactions with soil microorganisms, nutrient. storage

Question 6

root apex, root cap

Answer 6

root apical meristem is subapical and covered by root cap
func to protect apical meristem, prod mucigel and border cells (sloughed root cap cells)

Question 7

border cells

Answer 7

sloughed root cap cells
metabolically active, can divide, ALIVE
secrete carb-rich mucilage (released by root cap)
protect from biotic/abiotic challenges

Question 8

func of root hairs

Answer 8

root epidermis
single celled-extension produced by epidermal cells
inc SA of root
nutrient uptake

Question 9

secondary growth adaptation

Answer 9

lateral growth (trunk of tree)
strength and thickening allows for more extensive root systems
deep taproots access ground water during drought

Question 10

minnesota prairie

Answer 10

biomass greaater below ground than above

extensive root system allow to survive where drought is prevalent

Question 11

shoot complexity

Answer 11

nodes and internodes with leaves at each node (lateral organ)
axillary buds devel into lateral shoots (branches)
root apex does not prod lateral organs like leaves (just lateral roots)

Question 12

primary growth of stem

Answer 12

3 primary meristems
protoderm
ground meristem
procambium (vasc tissue)
no lateral woody growth

Question 13

parenchym

Answer 13

ground tissue
most abundant, thin walled cell
basic housekeeping (respiration, storage, photosyn)

Question 14

collenchym

Answer 14

ground tissue
unevenly thickend cell walls
rubbery/stretchy material
flexible support
more specialized

Question 15

sclerenchym

Answer 15

may or may not be living at maturity
thickened cell wall
can be short (sclerids/star like) or long and narrow (fibers)
structural support (sclerids make pear grit)

Question 16

xylem

Answer 16

conduction of water and nutrients, support

tracheids, vessel elements

Question 17

tracheids

Answer 17

xylem
have pits/pores thorugh which water travels between (no perforations)
conservative, diffuse water

Question 18

vessel elements

Answer 18

xylem
elongated cells with perforation
primarily in angiosperms
efficient flow of water between vessel elements

Question 19

problem with vessel elements

Answer 19

air bubbles, pull H2O too hard, bubble pass thru and block flow of water (embolism)

Question 20

phloem

Answer 20

living vcells, transport food materials and signaling molecules
superinformation highway

Question 21

mature sieve-tube element

Answer 21

phloem, living
angiosperms, no organelles like nucleus or ribosomes
rely on organelles from companion cells (carries out all metabolic functions)

Question 22

secondary growth from secondary meristems

Answer 22

first in lycophytes (separately)
lateral growth
formation of secondary xlyem (wood) and secondary phloem

Question 23

vascular cambium

Answer 23

prod secondary xylem and secondary phloem (between)

X,VC,P(cont generated)

Question 24

cork cambium

Answer 24

produces periderm

specialized dermal tissue

Question 25

bark

Answer 25

living phloem, periderm (cork cambium, cork!)
cork is most of bark
cracks and flakes as tree grows laterally

Question 26

common infection location in plants

Answer 26

stomata, epidermal cells covered with cuticle to min water loss

Question 27

calvin cycle

Answer 27

C is fixed in process of synthesizing simple sugars
CO2 enters thru stomata
C fixed by RuBisCo prod 3C compounds

Question 28

C3 pathway

Answer 28

ancestral
wheat, rice, most of plants
employ Callvin cycle (C3) in fixation

Question 29

rubisco problem

Answer 29

catalyzes initial rxn of calvin cycle (fix of CO2)

can also bind to O2 –> photorespiration (waste, yeild no E or fixed C)

Question 30

C4 pathway

Answer 30

drought, heat
close stomata to conserve water
spacial separation
C4 pathway in mesophyll cells
calvin cycle in bundle-sheath cell
PEP carboxylase has higher affinity for CO2 and makes 4C compounds
E expensive b/c movement steps

Question 31

CAM plants

Answer 31

temporal separation
crassulacean acid metab
Night: fix CO2 into 4C acids
Day: release CO2 to calvin cycle
Mesophyll cells
dry conditions
succulent leaves

Question 32

fungal endophytes members of what fungi phyla

Answer 32

ascomycota

Question 33

latitudinal gradient of fungal endophyte

Answer 33

more in tropical than boreal. same with diversity

Question 34

effect of fungal endophytes on plants

Answer 34

tradeoffs between cost and benefit

depends on quantity of endophyte (greater - greater cost and use of C)

Question 35

benefits of fungal endophyte

Answer 35

resistance to pathogens, resistance to herbivores, resistance to abiotic stress

Question 36

bad to have fungal endophytes

Answer 36

absense of stressors

nutrient poor enviro

Question 37

ex of protection from biotic challenges fungal endophytes

Answer 37

Dollar spot disease protectino from epcichloe typhina and neotyphodium typhinum (ascomycetes)

Question 38

fungal endophyte abiotic protection

Answer 38

hot springs, vents high heat
dichanthelium lanuginosum grass near heat
survive, more tolerant with endophyte

Question 39

agriculture and climate change fungal endophytes

Answer 39

rice
yield dec with temp
fungal endophyte could help by inc tolerance to heat, cold stress and drought tolerance

Question 40

fungal endophyte med

Answer 40

taxol and cancer
terpenoid from bark of pacific yew (taxus)
actually from the endophtye fungus

Question 41

fungal endophyte community struct

Answer 41

tall fescue (invasive) and neotyphodium coenophialum endophyte
helps invade better, better competitor

Question 42

transmission of fungal endophytes

Answer 42

horizontal - most, not related

vertical - mother to offspring, grasses (neotyphodium coenophialum)