exam 3 study guide

What three tissue types make up a plant?

dermal tissue, vascular tissue, and ground tissue

What tissues make up ground tissue?

parenchyma, collenchyma, sclerenchyma

Are the following plant tissues alive; parenchyma, collenchyma, and sclerenchyma?

parenchyma and collenchyma are both alive in mature tissue. sclerenchyma is dead at maturity.

What does the parenchyma tissue do?

repairs plant wounds (cellular division). contains mesophyll cells (photosynthesis).

what does collenchyma tissue do

supports rapidly growing parts (flexible). young stems, leaf stalks, petioles.

what does the sclerenchyma tissue do?

provides support and strength to non-growing parts of a plant.

What type of cells does the vascular tissue contain?

xylem and phloem

What does the xylem do?

conducts water and mineral ions

Is energy needed to transport water within the xylem?

no

What model is used to describe the transport of water within the xylem?

transpiration pull model; evaporation of water from plants. soil- root xylem- stem xylem- stem tracheids/ vessels- leaf tracheids/ vessels- mesophyll cells- atmosphere

What theory is used to describe transport of water within xylem?

cohesion- tension theory; 1) water tension; water molecules hang onto each other, as one molecule exists it pulls the following up, plant dries which increases tension due to less water. 2) water potential/ concentration; moves from area with high water potential to an are with low water potential.

What does the phloem do?

conducts sugars and other nutrients

What cells are found within the phloem?

companion cells, sieve tubes, phloem parenchyma, supportive cells like fibers and sclereids

Is energy needed to transport sugars within the phloem?

yes. uses energy -> active transport

What theory and model is used to describe how sugars are transported?

theory; pressure flow theory. model; source to sink model

How does the pressure flow theory work?

1) companion cells transports sugars against their concentration gradient into sieve tubes 2) inside sieve tubes: increase in solute concentration (causes lower water conc. inside, water moves out by osmosis) 3) increases water volume 4) increase in pressure causes sugar fluid to flow toward sink areas 5) sugar unloaded into sinks (high water conc. inside tubes)

how does the source sink model work?

source (high sugar conc.) (photosynthesis produces sugars companion cells load sugars into sieve cells) -> sink (low sugar conc.) (where sugar is needed or stored, roots and fruits). solutes moving down their conc. gradient, from high to low conc.

What does dermal tissue contain?

epidermis, cuticle, stomata, trichomes, guard cells, root hairs

What does stomata do?

found on underside of leaf, and balances CO2 intake and water loss.

What is the difference between monocots and dicots? How can you identify each?

Monocots have one cotyledon, while dicots have two. to identify dicots have flower parts in fours or fives, while monocots have flower parts in threes (multiple of 3)

What areas show growth in a plant? What are meristems?

growth; top of shoots, and root tip. meristems; localized regions of growth, cells continually divide rapidly.

What is primary growth? Do all plants show this?

The increase in length of a plant's roots and shoots, driven by cell division at the apical meristems located at the tips of these structures. All plants exhibit primary growth.

taproot root system

taproot: primary root, some branching, strong support, reaches water in deeper soil, dicots.

fibrous root system

fibrous: high amount of branching, complete well for water, shallow, reach across a large area, not a lot of suppert, monocots,

how does root hair adaptation help plants

root hairs: increase surface area.

how does mycorrhizae adaptation help plants

mycorrhizae "fungus roots": mutualistic relationship between plant roots and fungus, hyphae have large surface area, root cells get scarce materials that fungus absorbs better.

how does nitrogen fixation adaptation help plants

nitrogen fixations and root nodules: bacteria infect roots, plants lack enzymes to break N2, bacteria have enzyme, plants get nitrogen fixed, bacteria get an O2 free environment and sugars.

What is secondary growth?

roots and shots show woody growth

how does secondary growth differ from primary growth?

secondary has lateral meristems which thickens growth. vascular cambium; gives rise to secondary xylem and phloem. wood (inside) secondary xylem and bark (outside) secondary phloem

Do all plants show secondary growth?

no mainly found in trees and shrubs

What is the difference between heartwood and sapwood?

heartwood: old xylem sapwood: new xylem

What is the composition of the inner tree rings?

rings made of vascular cambium

What is the closest relative to land plants? What characteristics show that they are related?

closest relative is green algae called charophytes.

What challenges did plants need to overcome in order to become terrestrial - adapted to land"

support themselves against the pull of gravity, reduce evaporation/ water loss

Unique traits Bryophytes (mosses, liverworts, and hornworts)?

a waxy cuticle prevent dehydration. retention of developing embryos within female plant.

Unique traits Pterophyta/Tracheophyta (ferns and horsetails)?

evolution of vascular tissue and roots

Unique traits Gymnosperms (pines, spruces, firs, redwoods)

seeds, and pollen carries sperm

Unique traits Angiosperms

production of flowers and fruits.

moss reproduction

adult: gametophyte (haploid) water allows sperm to swim to the egg, fertilization occurs in female structure

embryo: sporophyte (diploid) develops in female structure, inside are haploid spores, released in moist soil, grow into new haploid male or female moss plants

ferm reproduction

prothallus (gametophyte): spore lands in moist soil, free living haploid stage, produces haploid gametes, sperm released into water to fertilize egg

adult fern (sporohptye): developed zygote diploid stage

gymnopserm reproduction

reproductive structure: cones

female: larger, ovules beneath scales of cones

male: smaller, release pollen (contain sperm)

gametophyte: haploid stage, cones

sporophyte: diploid stage, embryo, adult tree

angiosperm reproductive structure

male: stamen- anther (pollen grain= sperm) (haploid), filament

female: carpel/pistil- stigma, style, ovary (ovule cell= egg) (haploid)

How dependent are Bryophytes, Pterophyta/Tracheophyta, Gymnosperms, and Angiosperms on being in or near water?

bryophytes: very dependent

pterophyta: very dependent, but adapted to lane

gymnosperm: not dependent

angiosperm: not dependent

What is the difference between a gametophyte and sporophyte?

a gametophyte is the haploid (n) generation that produces gametes (sperm and eggs) through mitosis, while a sporophyte is the diploid (2n) generation that produces spores through meiosis

What is the advantage to producing seeds?

protects embryo, provides water and nutrients, not reliant on water for reproduction

How do the seeds of a gymnosperm differ from the seeds produced by angiosperms?

Gymnosperm seeds develop on the surface of scales or leaves, often in cones, and are not enclosed within a fruit. Angiosperm seeds are enclosed within a fruit, which develops from the ovary of a flower after fertilization.

What is the advantage to producing flowers?

pollen containing sperm separated by pollinators, no longer using wind or water for reproduction.

What is the difference between a perfect and imperfect flower?

perfect flowers: contains both male and female structures

imperfect flowers: contains either the male or the female structures not both

What is the difference between a monoecious and dioecious flower?

Monoecious plants have both male and female flowers on the same individual plant, while dioecious plants have male and female flowers on separate plants.

Know the structures of a flower.

Why is using a specific pollinator advantageous to just relying on wind or water?

bribery: plant offers something to pollinator, pollinator carriers pollen from one plant to another, safe place to deposit egg

trickery: plant deceives pollinator into carrying pollen from one plant to another, no payoff for pollinator

higher reproductive success, and high plant fitness

Why are flowers and insects considered to be co-evolved?

flower morphology defined by pollinator

What are some methods plants use to bring in pollinators?

sticky pollen, bright coloration or scent, and nectar

What is double fertilization?

two separate fusions of male nuclei from pollen grain with female nuclei in the ovule. embryo and endosperm (food source for embryo)

how does double fertilization work

pollen lands on the stigma

pollen tube grows down the style

delivers 2 haploid cells

(fertilizes the egg (n)= zygote (2n))

(fertilizes 2n larger cell= 3n endosperm)

What is a fruit? What is its purpose?

a fruit is a mature ovary. to attract animals into eating the seeds and dispersing them far away from parent plant

How are seeds dispersed?

wind, water, animals, gas explosion, spring landed dispersal

Why is dispersal away from the parent plant so important?

limits competition between parent and offspring

Why does a plant develop defenses?

to protect themselves from various threats in their environment,

What are some anatomical defenses?

spines, thorns, sticky, pitch, amber

What are some chemical defenses?

toxins and hallucinogens

How do we use plant defenses to our advantage?

we can use them to create medicines

How do fungus species obtain nutrients?

absorptive heterotrophy: secrete digestive enzymes, break down large molecules found in their environment, absorb them thru cell membranes

What is the basic evolutionary history of fungus?

evolved from unicellular protist with flagellum

What are the opisthokonts? Synapomorphies?

opisthokonts: fungi, animals, choanoflagellates

opisthokont synapomorphy: posterior flagellum, flagella of other eukaryotes anterior

fungus synapomorphies: absorptive heterotrophy, chitin in cell walls (nitrogen containing polysaccharide)

What are the characteristics unique to fungi?

Their cell walls contain chitin, unlike plants which have cellulose. absorptive heterotrophy. reproduce through spores

What is the difference between unicellular and multicellular fungi?

unicellular: yeast, free living, absorb nutrients across cell membrane, reproduce by budding, can reproduce sexually

multicellular: mycelium composed by hyphae (absorb nutrients), septate- pores allow organelles, nuclei controlled movement between compartments

What is the body structure of a fungus?

mycelium: body of fungus which is composed of hyphae

hyphae: individual filaments, absorbs nutrients, penetrate small spaces

What type of growth do fungus species show?

rapid growth: widely dispersed, clumped, fruiting body you see mushroom clumps, spores

How do fungi interact with their environment?

large surface area to volume ratio of filaments hyphae.

benefit: absorbing a lot of nutrients.

cost: loses water easily in dry environments

What purpose do fungus spp. serve?

principle decomposers, recycle materials and nutrients needed by living organisms, main component of earths carbon cycle (releases large quantity of carbon atoms into atmosphere)

Facultative fungus?

can grow on living organisms, can grow independently

Obligate fungus?

grow only on a specific living host, plants and insects, specialized nutritional requirements, hyphae invade plants

How do parasitic fungi obtain nutrients?

branching projects push thru cell walls into living cells, absorb nutrients, form fruiting structures

What are pathogenic fungi?

ringworm, athletes foot, ergots (fungal heads infecting seed heads of crop plants), valley fever (breathe in fungal spores, spreads from lungs to other parts of body), chytridmycosis (responsible for amphibian decline)

What are predatory fungi? What different ways do they obtain nutrients?

function as active predators, trap nearby protists or animals. secrete sticky substances from hyphae (spread thru body and absorb nutrients). form constricting ring (nematode crawling thru rings stimulates fungus rings, hyphae invade and digest)

What is lichen? What organism are they composed of?

symbiotic or mutualistic relationship.

Fungus: base for growth water retention

algae: nutrients via photosynthesis

yeast: antimicrobial compounds, protection of lichen

What are the three body types of lichen? How do you tell the difference between them?

crustose: spray paint

foliose: leaf life and lays parallel to substrate surface

fruticose: looks like small shrubs or trees

What is mycorrhizae?

mutualistic associations of fungi and roots

What type of relationship does mycorrhizae have with plants?

mutualistic

fungus: receives organic compounds from plants

plants receive: greater amount of water and minerals

Ectomycorrhizae

fungus wraps around plant roots, hyphae wrap around individual cells, increase surface area of roots

Arbuscular

penetrate cell walls of root cells, form treelike structures inside cell wall, form vast webs of hyphae leading from root surface into soil

Endophytic

fungi that live within above ground parts of plants

What traits are characteristic of all animals?

acquire energy by consuming others, ability to move, multicellular

What are the four key distinctions that are used to separate animals into the differentphyla?

1) specialized cells forming defined tissues

2) symmetry

3) gut development

4) organisms growth

What makes porifera different from the other phyla (groups)?

lacking true tissues and organs, and having a unique cellular organization

what makes cnidaria different from the other phyla?

1. Two body forms (Medusa & Polyp)
2. Stinging cells (cnidocytes)
3. Diploblastic
4. Radial symmetry
5. Tentacles armed with stinging cells (cnidocytes with nematocysts) - Coiled thread with barbs (inside) & trigger outside

what makes nematoda different from other phylum?

grow by molting, pseudocoelmate, soil dwelling, parasitic

what makes platyhelminthes different from other phyla?

bilateral, grow by adding body mass, no body cavity (acoelomate), hermaphroditic (sexual and asexual reproduction)

what makes annelida different from other phylum

1. Round Body
2. Segmented
3. Grow by adding body mass
4. Grooves around body mark segments
5. Bilateral symmetry
6. Coelomate

what makes mollusca different from other phylum

bilateral, shell, mantle, muscular foot

what makes anthropoda different from other phylum

tagmata, jointed legs, exoskeleton

what makes echinodermata different from other phylum

endoskeleton, water vascular system, outer covering of hard spiny skin,

Phylum Porifera (Sponges)

Classes & Examples:

Calcarea – Leucosolenia, Sycon (calcium carbonate spicules)

Hexactinellida – Glass sponges like Euplectella

Demospongiae – Most sponges, including bath sponges (Spongilla)

Phylum Cnidaria (Cnidarians)

Classes : Hydrozoa

• ex: Hydra, Obelia, Portuguese man o’ war

Classes: Scyphozoa

• ex: True jellyfish like Aurelia

Classes: Anthozoa

• ex: Corals, sea anemones

Phylum Platyhelminthes (Flatworms)

Classes & Examples:

Turbellaria – Free-living flatworms like Planaria

Trematoda – Flukes like Schistosoma

Cestoda – Tapeworms

Phylum Annelida (Segmented Worms)

Class: Polychaeta

• Organisms: Bristleworms (Clam worm)

Class: Clitellata

• Organsims: Earthworm

Class: Hirundinea

• Organisms: Leeches

Phylum Mollusca (Mollusks)

Classes & Examples:

Gastropoda – Snails, slugs, sea slugs

Bivalvia – Clams, mussels, oysters, scallops

Cephalopoda – Octopus, squid, cuttlefish,

Polyplacophora – Chitons

Phylum Nematoda (Roundworms)

Representative Examples (no formal classes used in basic taxonomy): Ascaris lumbricoides (intestinal roundworm)

Phylum Arthropoda (Arthropods)

Subphylum: Chelicerata
Class: Arachnida

• Organisms: spiders & scorpions

Subphylum: Myriapoda

Class: Diplopoda

• Organisms: millipedes

Subphylum: Myriapoda

Class: Chilopoda

• Organisms: Centipedes

Subphylum: Crustacea

• Organisms:  Crabs, Lobsters, Crayfish, Barnacles, Shrimp, Mantis shrimp, Woodlice/pill bugs/ roly polies, Prawns, Krill

Class: Insecta

• Organisms: Beetles, Butterflies