exam 1

Question 1

autotroph

Answer 1

Plants are autotrophs –> organisms that can convert abiotic sources of energy into energy stored in organic compounds, which can be used by other organisms

Question 2

sessile

Answer 2

plants are sessile –> fixed in one place
substitute for mobility with indeterminate growth –> they will continue adding new organs (leaves, stems, roots) as long as they have access to the necessary resources

Question 3

plant support

Answer 3

plants are supported against gravity by structural reinforcement –> cell walls and lignin

Question 4

plant characteristics

Answer 4

autotrophs, sessile but indeterminant growth, have structural reinforcement, have mechanisms to reduce and control evaporative water loss and to move water, nutrients, and photosynthates throughout the plant

Question 5

QUIZ 1 Q: name the growth habit in plants that substitutes for motility

Answer 5

indeterminant growth

Question 6

innovations in plants

Answer 6

green algal ancestor at base –> add waxy cuticle and gametangia (mosses, liver worts, hornworts) –> add vascular tissue (whisk ferns, club mosses, horsetails, ferns) –> add seeds (gymnosperms) –> add fruit (angiosperms)

vascular tissue: comprised of the xylem and the phloem: main transport systems of plants. traversing roots, stems, and leaves

Question 7

QUIZ 1 Q: what is the defining anatomical innovation for angiosperms?

Answer 7

fruit

Question 8

angiosperms have two categories

Answer 8

monocots
- one cotyledon
- pollen grains have one pore or furrow
- flowers have 3 floral parts (or multiples thereof)
- leaves are narrow, with parallel veins
- vascular bundles small and spread throughout stem
- fibrous roots

eudicots
- two cotyledons
- pollen grains have 3 pores or furrows
- flowers have four or five floral parts (or multiples thereof)
- leaves are oval or palmate with net like veins
- vascular bundles arranged in a ring around stem
- tap roots

Question 9

cotyledon

Answer 9

seed leaf within the embryo of a seed, helps supply nutrients a plant embryo needs to germinate

Question 10

monocots

Answer 10

• one cotyledon
• pollen grains have one pore or furrow
• flowers have 3 floral parts (or multiples thereof)
• leaves are narrow, with parallel veins
• vascular bundles small and spread throughout stem
• fibrous roots

Question 11

eudicots

Answer 11

two cotyledons
- pollen grains have 3 pores or furrows
- flowers have four or five floral parts (or multiples thereof)
- leaves are oval or palmate with net like veins
- vascular bundles arranged in a ring around stem
- tap roots

Question 12

plant organs

Answer 12

3; roots, stems, leaves

Question 13

meristem

Answer 13

meristems are centers of cell division and growth. plants contain embryonic tissue throughout their lives (indeterminant growth)

Question 14

QUIZ 1 Q: which meristem is responsible for the formation of axillary buds?

Answer 14

shoot apical meristem

Question 15

primary plant meristems

Answer 15

root + shoot
- meristems that are initiated at opposite poles of the plant embryo
- contain stem cells, which remain undifferentiated and supply new cells for growth and the formation of tissues
- they produce 3 types of primary meristems
1. protoderm –> epidermis; surrounds plant
2. ground meristem –> ground tissue; generalized functions: photosynthesis, storage, support
3. procambium –> vascular tissue, functions in transport

Question 16

secondary plant meristems

Answer 16

increases plant girth
1. vascular cambium –> arises from the procambium and pericycle in roots. in stems, from procambium cells of the vascular bundles and parenchyma cells –> gives rise to secondary phloem and secondary xylem
2. cork cambium –> arise from the pericycle in roots and parenchyma cells in stem –> produces periderm, secondary dermal tissue and a component of bark

Question 17

dermal tissue – overview

Answer 17

dermal tissue refers to the plant epidermis, the outer layer of tissue that surrounds the primary body of vascular plants. Includes the roots, stems, leaves, flowers, fruits, and seeds. the dermal layer does not contain chloroplasts and is typically composed of a single layer of tightly packed cells. Helps deter excess water loss and invasion by insects and microorganisms + works in transpiration and gas exchange

Question 18

dermal tissue – cells

Answer 18

parenchyma cells, stomatal guard cells, trichomes (glandular/non glandular), bulliform (hinge) cells, root hairs

Question 19

ground tissue – overview

Answer 19

not dermal or vascular, these cells store molecules (commonly starch), photosynthesize, or support the plant

Question 20

ground tissue – cells

Answer 20

parenchyma cells, collenchyma cells, sclerenchyma cells

Question 21

parenchyma cells

Answer 21

spherical, elongates cells with a thin primary wall. main component of young plant organs. main functions = photosynthesis + storage. totipotent so important in regeneration. can dedifferentiate and redifferentiate

Question 22

collenchyma cells

Answer 22

living supportive tissue that has elongated cells and unevenly thickened cell wall. main function is the mechanical support of young stems and leaves via turgor (allows for cellular expansion)

Question 23

sclerenchyma cells

Answer 23

dead supportive tissue that consists of long sclerenchyma fibers or sclereids. fibers occur in groups (bundles). secondary wall is rich in lignin. main function is support of older plant organs (make fruit inedible b4 ripeness). w/o sclerenchyma (+ if not watered), leaves will droop bc vacuoles will decrease in size. cell expansion not possible (lignin ?)

Question 24

plant v animal cells

Answer 24

eukaryotic and similar to animal cells but with important differences in genome, plastids, micro bodies, vacuoles, and cell wall

Question 25

plant cell genome

Answer 25

large, variable (polyploidy -- 2n, 3n, 4n, etc), nucleus appearance differs --> large central vacuole makes nucleus "squished"/ may not be right in the center of the cell

Question 26

plant cell plastids

Answer 26

-"plastikos" means molded, interconvertible (can change into others unless too far down specialization, double membrane bound - to figure out function look @ pigments, storage and internal membrane ---> look at figure in notes

Question 27

plastid -- pro plastid

Answer 27

no internal membrane, pigment, storage minute cytoplasmic body from which a plastid is formed !!

Question 28

plastid -- etioplast

Answer 28

prolamellar body as internal membrane, no pigment, no storage intermediate type of plastid that develop from proplastids and have no even exposed to light yet. can covert to chloroplasts

Question 29

plastid -- chloroplast

Answer 29

thylakoids (grana) as internal membrane, pigment is chlorophyll, storage is pigment

Question 30

plastid -- chromoplast

Answer 30

internal membrane, pigment is carotenoids (act in leaves in fall when chlorophyll breaks down), storage is pigment

Question 31

plastid -- leucoplasts

Answer 31

subtypes 1. amyplasts store starch 2. proteinoplasts store protein 3. elaioplasts store lipids

Question 32

amyplasts

Answer 32

store starch

Question 33

proteinoplasts

Answer 33

store protein

Question 34

elaioplasts

Answer 34

one of the forms of leucoplasts specialize in oil synthesis + store lipids

Question 35

plant cell microbodies

Answer 35

single membrane bound -- original off the ER, different metabolic functions (enzymes) subtypes: peroxisome, glyoxysome, oleosome

Question 36

microbody - peroxisome

Answer 36

oxidation of organic substrates, catalase - crystal, photorespiration (btwn 3 different organelles - chloroplast, mitochondrion, peroxisome)

Question 37

microbody - glyoxysome

Answer 37

oxidation of fatty acids, metabolism of glycolate

Question 38

microbody - oloesome

Answer 38

stores fatty acids, oil bodies are bounded by a half unit membrane ( a single phospholipid layer), derived from smooth endoplasmic reticulum, NOT truly a microbody -- storage by not many enzymes

Question 39

plant cell vacuoles

Answer 39

large, single membrane (tonoplast) bound filled with water and solutes (enzymes, nitrogen compounds, sugars, anthocyanines (subgroup of phenolics, red coloration), tannins (anti-herbivory), potassium) - lytic comportment (like a lysome in animal cells)

Question 40

QUIZ 1 Q: explain statement -- "plastids in nectaries can be responsible for floral scents"

Answer 40

synthesize essential oils

Question 41

QUIZ 1 Q: the bark of trees consists of all tissue outside of the...

Answer 41

vascular cambium

Question 42

QUIZ 1 Q: all xylem elements in angiosperms are perforate

Answer 42

false

Question 43

QUIZ 1 Q: the evolutionary innovation suggested to have coincided with plants becoming terrestrial (and thus an important adaptation to terrestrial environment is...

Answer 43

lignification

Question 44

QUIZ 1 Q: name the micro body closely associated with chloroplast metabolism + found near chloroplasts in plant cells

Answer 44

peroxisome

Question 45

QUIZ 1 Q: in plants that have leaves floating on the surface of water, most stomata would be expected to occur on the upper surface which is also referred to as the ... surface

Answer 45

adaxial

Question 46

QUIZ 1 Q: collenchyma is typically found in which of the following tissue types?

Answer 46

ground tissue

Question 47

cell wall functions

Answer 47

1. structure/shape/turgor 2. strength/protection 3. metabolic function -- some proteins may be enzymes "in muro" 4. (CH2O)n storage 5. recognition/signaling 6. permeability control

Question 48

cell wall layers

Answer 48

outside --> inside 1. middle lamella 2. primary wall 3. secondary wall 4. plasma membrane walls consist of (cellulose) microfibrils in a matrix (hemicellulose, pectin, proteins, starch)

Question 49

cell wall - middle lamella

Answer 49

furthest from cytoplasm; functions as a cementing layer/acts like glue btwn primary walls of adjacent cells - rich in pectin (functions in cell adhesion)

Question 50

cell wall - primary wall

Answer 50

2nd furthest from cytoplasm, cellulose containing layer, allows for expansion and is first line of defense/ shape

Question 51

cell wall - secondary wall

Answer 51

2nd closest to cytoplasm,, not in every plant cell, added for extra rigidifying layer and mechanical support - sublamelli (i think name is wrong lol) + lignin important for strength

Question 52

cell wall - plasma membrane

Answer 52

closest to the cytoplasm, important for transport and sensing

Question 53

cell wall - microfibrils

Answer 53

made of cellulose --> polymer of glucose ( beta 1,4 glucose ) - intermolecular H bonding hold many parallel strands together to create microfibrils - provided strength to the cell wall and adds rigidity; maintain shape through turgor pressure, resists infection

Question 54

cell wall - cellulose v starch

Answer 54

molecular structure looks similar --> starch have OH groups in identical orientation while cellulose has rotating - starch: alpha 1,4 glycosidic bonds with INTRAmolecular H bonding, allows starch to fold up on itself - insoluble; functions as an energy store

Question 55

cell wall - polysaccharides + proteins

Answer 55

in the matrix: hemicellulose, pectin, extensin

Question 56

cell wall - hemicellulose

Answer 56

contains sugar branches that act as an interface with the microfibrils and aids in holding everything in the matrix together (with the branches)

Question 57

cell wall - pectin

Answer 57

polygalacturonic acid - 4 different types of branching: sticks together 'gel', acid helps iron bind --> calcium bridges

Question 58

cell wall - extensin

Answer 58

a wall protein - hydroxyproline rich (amino acid) , structural support

Question 59

cell wall chemical modification -- lignin

Answer 59

for strengthening--> strong, tough, decreases permeability, infiltrates spaces in sites, polymerization of aromatic alcohols found in and between the cell walls of plants, hydrophobic properties, and promotes mineral transport through vascular bundles in plants

Question 60

cell wall chemical modification -- cutin + suberin

Answer 60

"water proofing" - cutin works on outer epidermal wall and suberin works on inner wall cutin: seal cuticle of the epidermis , prevents against uncontrolled water loss suberin: in periderm of barks and underground organs - casparian strips found in the roots of all higher plants. hydrophobic cell wall. occur in the endodermis- surrounds the central vascular strand of roots. EXODERMIS --> alters what can enter steele, apoplastic barrier,

Question 61

cell wall - primary v secondary

Answer 61

primary characteristics secondary less cellulose more smaller microfibrils larger more pectin less less extensin more (sclenchyma) no lignification yes

Question 62

cell wall formation -- cytokinesis

Answer 62

cell plate formation (middle lamella) - golgi vesicles containing pectin substances fuse - final stage of cell division - contractile ring composed of actin filaments forms inside plasma membrane --> pull to create cleavage until in two (almost). new cell wall must develop. golgi vesicles (full of pectin) line at dividing cell equator and fuse + coalesce to create the cell plate. elongates until it fuses with the cell walls at the periphery of the cell. ER trapped between the fusions

Question 63

cell wall formation -- addition of matrix material

Answer 63

matrix materials come from the golgi body - vesicle from rough ER --> golgi body --> collects matrix polysaccharides --> plasma membrane and cell wall add more

Question 64

cell wall formation -- formation of microfibrils

Answer 64

cellulose chains assemble spontaneously into microfibrils that form on the extracellular surface of the plasma membrane - cellulose microfibrils formed at plasmalemma in cellulose synthase (CesA) complexes - rosettes add more

Question 65

organization of microfibrils

Answer 65

- cellulose synthase moves relative to wall - microtubules influence movement of cellulose synthase and hence the orientation of microfibrils add more

Question 66

plasmadesmata

Answer 66

surrounding of plasma membrane with desmotubule, spikes + connections all the way through -- filamentous protein from tubules to edges - what can go through? dyes used to see if there's open passage --> dyes of diff molecular weight to show size exclusion limit of 700 to 2000 daltons (can change - suggestion that actin and myosin can facilitate a change) -ions can go through, electrical impulses, small proteins, small molecules, viruses (AT size exclusion limit -- needs to be pulled through) - closed by allows

Question 67

water molecule

Answer 67

polar molecule with a net negative charge on the oxygen side and net positive charge on the hydrogen side - attraction of bonding electrons to the O creates local partial charges

Question 68

properties of water

Answer 68

liquid @ room temp, constant volume, high specific heat, high heat of vaporization, high cohesive/ high adhesion force, colorless, strong solvent

Question 69

liquid @ room temp

Answer 69

not usual for molecule this size -- usually gas

Question 70

constant volume

Answer 70

NOT compressible --> important for cell turgor (cytoplasm pushing against wall)

Question 71

high specific heat

Answer 71

water buffers temp changes --> due to H bonding which absorbs some of the heat - important in aquatic environments/ coastal. day-night temps - succulence (high H2O content), why cacti can survive in deserts

Question 72

high heat of vaporization

Answer 72

water resists evaporation due to H bonding - evaporation cools, for plants: transpiration which is loss of water vapor to cool leaves down

Question 73

high cohesive force/ high adhesion force

Answer 73

both due to the H bonding - cohesive is between water molecules (surface tension -- "skin") and adhesive is between water and a surface (capillarity: movement of water within narrow capillary tube or within the cell wall) - tensile strength: ability to resist a pulling force

Question 74

colorless

Answer 74

allows light to penetrate through leaves an in aquatic environments

Question 75

strong solvent

Answer 75

forms "cage" around solutes

Question 76

water movement -- bulk (or mass) flow

Answer 76

pressure difference (high to low) -- mechanism to generate pressure gradient - h2o crossing a plant cell membrane

Question 77

water movement -- diffusion

Answer 77

h2o crossing a plant cell membrane - movement of molecules due to random thermal agitation from an area of high free energy (concentration) to an area of low free energy (lower concentration) - movement stops when dynamic equilibrium is achieved osmosis: diffusion of a solvent across a membrane dialysis: diffusion of a solute across a membrane

Question 78

predicting flow: water potential

Answer 78

- water moves down a water potential gradient, from higher to lower potential - quantify description of the free energy status of water - derived from 1st and 2nd laws of thermodynamics (2nd: the total entropy of an isolated thermodynamic system tends to increase over time, approaching a max value or equilibrium) - approximately the chemical potential of water - chemical potential of water in a system, expressed in unit of pressure and compared to the chemical potential of pure water under atmospheric pressure and at the same temperature; the chemical potential of pure water is arbitrarily set at zero

Question 79

gibbs free energy

Answer 79

also derived from 1st and 2nd laws of thermodynamics - combines the enthalpy and entropy of a system G=H-TS G= gibbs free energy H= enthalpy T= temp in kelvin S= entropy - free energy change is a measure of the spontaneity of a process and of the useful energy available from it - G < 0 = spontaneous process - G = 0 = process at equilibrium - G > 0 = non spontaneous

Question 80

chemical potential

Answer 80

- free energy per unit quantity of substance - a large volume of water has more free energy than a smaller one under otherwise identical conditions - thus it is convenient to consider the free energy of a substance in relation to some unit quantity of the substance

Question 81

components of water potential

Answer 81

Yw = Ys + Yp + Yg s= solute p=pressure g= gravity -- will be ignoring, only important in very very tall trees

Question 82

solute potential

Answer 82

colligative property: dependent on #, NOT type of particles though dissociation of salts produce more particles Ys of 0.1 M sucrose = -0.26 MPa Ys of 0.1 M NaCl = -0.52 MPa more interaction of h2o molecules w solutes decreases freedom to move, takes up space against membrane and decreases water potential

Question 83

pressure potential

Answer 83

apply positive pressure to plunger increase the freedom of h2o to move, think of syringe full of water and it shooting out when pressure is applied --> Y increases and is positive apply -VE pressure, decrease the freedom of water movement, Y decreases and is negative --> think of suction Yl > 0 Yr=0 -----> movement to the right Yl < 0 Yr=0 <----- movement to the left

Question 84

turgor potential

Answer 84

special case of Yp - increased Yt = increased likelihood of water to move out - increase in Y of a cell due to the inward +VE pressure of the plant cell wall is Yt - always positive or 0 plasma membrane pressing hard against the cell wall (outward expansion pressure) and inward counter pressure from cell wall

Question 85

isotonic

Answer 85

solution has the same Y as the cell. no net movement in/out of the cell

Question 86

hypotonic

Answer 86

solution has a higher potential than the cell so there is net movement in to the cell - as water enter the cell, Ycell increases due to dilution of solute - cell has water requirement, cell swells, turgor potential increases - increases until Ycell = Ysolution to reach equilibrium, no more net movement

Question 87

hypertonic

Answer 87

Ysolution is less than Ycell, net movement out of the cell - cell shrinks and plasma membrane moves from cell wall (less interaction) and turgor decreases - as water moves out, Ys decreases, Y turgor decreases until theoretical equilibrium (not always since solution doesn't have finite volume to make water go back into cell) --> if no equilibrium = plasmalyzed plasmalyzed= cytoplasm no longer pushing against cell wall; incipient plasmolysis --> no more turgor. full plasmolysis is not common in nature