Exam 1 - BIOL 1106

etiolation

pale yellow color, thin, weak -caused by lack of red light

symplast route

strict transport through plasmodesmata

phloem translocation: loading

sucrose enters phloem via active transport, sucrose and water removed at sink via osmosis -continues through phloem to sinks via passive transport

phytoaccumulation

the plants takes in contaminant and stores it in shoots plant is removed and typically destroyed

phototropin II associated with

Golgi Apparatus

Vascular tissue

Xylem & Phloem moves water and nutrients against gravity

Are cations or anions more readily available to plants?

anions

____ in solution create a graident causing protons to exit root (using active transport)

anions

meristems that aid in root and shoot extensions

apical -located at tips of stems and roots -give rise to primary tissue -root cap - protects root apical meristem -leaf primoridia- protects shoot apical meristem

waters intermembrane channels

aquaporins -enhances osmosis across membrane (moves water fast) -doesnt change direction

"sun-shy hormone"

auxin - produced in shoot tip apical meristem

what hormone is a gas?

ethylene

"ripening hormone"

ethylene -gaseous -surppresses stem elongation

In shoot gravitropism _____ have increased auxin concentration on the lower side which causes that area to grow more than the cells on the upper side resulting in bending.

horizontal stems

Abscission

protective and seperation layer

Advantages of the seed?

protects embryo from desiccation -acts as food supply increased dispersal range -pollen grain

water and mineral absorption

root hairs -rot pressure moves water up the xylem

Even in the absence of transcription, some water can move into the roots and partially up the xylem columns. This phenomenon is due to

root pressure

two groups of seed plants?

angiosperms gymnosperm

P(r)

absorbs red light -found in cytoplasm -sunlight chnges Pr - Pfr

transpiration

"the pulling force" movement of water through a plant and its evaporation from leaves

roots

"the pushing force" caused by water entering roots but water moves against gravity via xylem

Soil characteristics

-highly weathered outer layer -composed of sand, rocks, silt, clay, humus, minerals -full of microorgansims that are important in soil breakdown

soil micronutrients

Cl, Fe, Mn, Zn, B, Cu, Mo

gravitropism

directional growth based on gravitation field of earth

What cells lack living protoplasts at maturity?

sclerenchyma

main component of wood

secondary xylem

allelopahtic plants secrete chemicals to block ______ or inhibit ___ of nearby plants

seed germination; growth

defensins

small, cyteine-rich peptides w/ antimicrobial properties some can limit protein synthesis

pressure flow hypothesis

source -> sink phloem translocation: loading

source to sink

source = photosynthetic levels sink = growing stems, root tips, and fruits

phytodegredation

the plant breaks down the contaminant into other components

phytovolatilzation

the plant take in the pollutant and releases it through stoma

Bryophytes

-nonvascular (not tracheophyte), seedless, flowerless plant -lack a true root system (rhizoids absorb the small amount of water) -repro aided by water -gametetophyte dominant -closest living decendants of first land plants

dormany induced by increases in ____

ABA

soil macronutrients

C, H, O, N, K, Ca, Mg, P, S

Phytochrome-red enters the plant cell nucleus and regulates gene expression.

False

Tracheophytes

First vascular plants -true roots, waxy cuticle, stomata

"Alterations of Generations"

Haplodiplontic cycle Diploid = sporophyte Haploid = gametophyte

mineral and organic soil particles tend to have ____ charges, so they attract ____ charged molecules and ions. The charge gradient produced in the soil solution causes ___ charges to tend to move out of the root hairs.

Negative; positive; positive

The ____ hypthesis explains the translocation of carbohydrates in the phloem tissue.

Pressure-flow

You can determine the age of an oak tree by counting the annual rings of ____ formed by the _____.

Secondary xylem; vascular cambium

P(fr)

absorbs far red light (active -binds to proteins that form transcription complex -expression via protein kinase-signaling pathways

Water molecules can "stick" to other surfaces by

adhesion

gravity sensing mechanism called

amyloplasts

Long day plants require ____ to trigger a flowering response

an uninterrupted dark period that is less than the critical length for that species

Enclosed seeds

angiosperms

rhizobia (not to get confused with rhizoids)

bacteria that fix atmospheric N2 into nitrate for plants

"steroid wannabe"

brassinosteroids -effects most everything in growth

Which plant group has a dominant gametophye generation?

bryophytes

positive potential

caused by water entering roots

pulvini

cell clusters at leaf base that change turgor pressure

zone of maturation

cells specialize into xylem, phloem, etc.

turgor is most directly related to the plant cells'

central vacuoles and cell walls *

phototropin I has two light sensing regions that ________ b/c blue light. stimulates ____ --> signal transduction

change conformation; autophosporylation

"sister group" to all land plants?

charophytes

Which of the following would not be considered a macronutrient for plants?

chlorine

meristems

clumps of cells with dense cytoplasm and large nuclei that undergo mitosis -indefinite mitotic divisions --cells begin to differntiate *think stem cells*

produces outer bark

cork cambium

Which of the following chemical defenses is common to plants and animal and provides antimicrobial activity?

defensins

phototropism

directional growth based on light (blue light photoreceptors) -auxin present on particular side of plant causes growth

thigmotropism

directional growth in response to physical contact

if plant lacks R gene or an avr gene, then

disease occurs

cytokinin stimulates cell ____ and _____. Produced in the____ and promotes growth of ______ on branches.

division; differentiation; root tip; lateral buds (inhibits lateral root formation)

seed germination is inhibited by _____ and stimulated by ____. germinates when in direct ____sunlight

far red light; red light; direct

Which innovation likely contributed to the tremendous success of angiosperms?

fruits that enhance dispersal

Guard cells/ stomata (dermal tissue)

gas exchange and water diffusion

"growing buddy hormone"

gibberellins -promotes germinations w/ auxin -enhances stem elongation

The leaf mesophyll is composed of parenchyma cells and makes up the ____ tissue of the leaf.

ground

primary meristem that forms ground tissue

ground meristem

Parenchyma, collenchyma, and sclerenchyma are all types of cells in the...

ground tissue

storage, photosynthesis, and secretion layer of tissue

ground tissue

____ regulate the opening and closing of the stomata

guard cells

Which term means "nakes seed?"

gymnosperm

"naked seed"

gymnosperms -ovule (unfertilized seed) exposed -lacks fruits&flowers to cover ovule

root hairs (dermal tissue)

increase surface area for water and mineral absorption

meristems that increase girth of systems

lateral -found in plant exhibiting secondary growth -woody plants have two types

flower development pathways

light, temperature, gibberellin-dependent, and autonomous

zone of cell division

location of apical meristem, cells grown prior to specialization

Reproductive strategies of angiosperms

male gametophyte -pollen grains contain 2 sperm Female gametophyte -egg & polar nuclei Double fertilization

pollen

male gametophyte containing sperm

which process produces haploid spores during alternation of generations?

meisosis

transmembrane route

membrane transport between cells and across membranes of vacuoles within cells -permits greatest control

What provides nutrients, protects against invasion of foreign pathogens for the plant?

microrrhizae (fungi) symbiotic relationship

ground tissue- parenchyma

most abundant -thin walls, large vacuoles, many chloroplasts -alive at maturity

although symbiotic relations between nitrogen-fixing bacteria and plants are rare, many plants have symbiotic relationships with

mycorrhizal fungi in the soil

soil particles that are ______ attract cations in solution that are _____

negative; positive

if plant has R gene that recognizes the avr gene, then

no disease

photomorphogenesis

nondirectional, light-triggered development -seed germination, flower development, stem elongation

immunity initiator

oligiosaccharins

double fertilization

one sperm fuses with egg to form zygote (diploid) one sperm fuses with polar nuclei to form endosperm (triploid)

Dermal tissue

outer, protective layer of tissue (forms epidermis) -covered in fatty cutin layer -contains special cells

the wounded leaf produce small ___ called ___. systemin moves through the plant ____ into ____. Once it reaches an appropriate membrane-bound receptor, it initiates the production of _____. JA in turn elicits ____ for the transcription of a proteinase inhibitor

peptide, systemin; apoplastically, phloem; jasmonic acid (JA); gene expression

What is not a plant characteristic that is an adaption for a terrestrial environment?

photosynthesis

2 components of water potential

physical forces- turgor pressure solute concentration

plants can remove harmful chemicals from the soil by the process of:

phytoremediation

phytochrome

pigment molecule

gene-for-gene hypothesis

plants have a resistance gene (R) pathogens have avirulence gene (avr)

auxin increases the _____ of cell walls and is involved in _____

plasticity; stem elongation

water potential

predicts movement of water -moves from high to low -megapascals

primary meristem that produces primary vascular tissue

procambrium

Root cap

protect apical meristem, cell continually replace, secrete slime

primary meristem that forms epidermis

protoderm

____ in the solution cause soil to release cations. cations are then taken in by _____

protons; root hairs

shoot elongation has normal growth and color in _____ light

red

Trichomes (dermal tissue)

reduce evaporation, protect from harsh light, can secrete toxins

zone of elongation

root elongates as vacuoles enlarge

Most of the water that evaporates from leaves passes out through the

stomata

apoplast route

strict transport through cell walls and space between cells -can be blocked by casparian strip

Desiccation

tendency to lose water to the air Overcome this by covering its cuticle

Cation Exchange Capacity (CEC)

the capacity of a soil to attract/hold positively charged ions

ground tissue- collenchyma

thick walls, provide flexibility and support -alive at maturity

ground tissue- sclernchyma

thick walls, secondary walls contain lignin -dead at matruity

cuticle

thick, protective coating that limits gas exhange

which plant growth response does not involve phytochrome?

thigmotropism

____ transportation routes

three

negative potential

top of plant; due to transpiration or water loss

the hypersensitive response (local)

triggered by invasion of pathogen and appropriate R gene -plant begins to cause local cell death around site -sudden apoptic signals are generated (NO and H2O2) -seals off pathogen to that site

the wound response

triggered by mechanical wounds from chewing or injury

systemic acquired resistance (broad-range)

triggered by second invasion of pathogen -signaling molecule initiaes SAR -enables the plant to respnd quicker -uses salicylic acid and JA

Vascular tissue: Phloem

two types: sieve cells- seedless, vascular, gymnosperms sieve tube members -angiosperms

phytoremdiation

use of plants to concentrate or breakdown pollutants (3 processes)

produces secondary vascular tissue

vascular cambium

conduct fluids, nutrients, and hormones

vascular tissue

Vascular tissue: Xylem

vessels- large diameter hollow tube w/ perforation plate tracheids- small diameter hollow tubes w/ pits

total water potential

water moves from high concentration to low concentration