PLANTSPLANTS PartsParts ClasificationClasification ReproductionReproduction

Parts of a Vascular PlantParts of a Vascular Plant

vertical axisvertical axis Underground: Underground: root root to to

absorb water and ions absorb water and ions and anchorand anchor

above ground: above ground: shoot:shoot: stem serves as a stem serves as a

framework for framework for positioning the leavespositioning the leaves

Leaves: photosynthesis Leaves: photosynthesis takes placetakes place

growth zones: growth zones: unspecialized cells unspecialized cells called called meristemsmeristems

Tissue TypesTissue Types

1.1. DermalDermal: : outer protective coveringouter protective covering covered by a waxy layer called the covered by a waxy layer called the cuticle, cuticle, effective effective

barrier against water lossbarrier against water loss

2.2. VascularVascular: 2: 2 types types XylemXylem

water and minerals pass from the roots to the shoots, when water and minerals pass from the roots to the shoots, when water reaches the leaves, most exits through the stomatawater reaches the leaves, most exits through the stomata

PhloemPhloem principal food-conducting tissueprincipal food-conducting tissue

1. Roots1. Roots

Main Roots have:Main Roots have: central column of central column of xylemxylem alternating are strands of alternating are strands of phloemphloem surrounding the central column, a cylinder of cells surrounding the central column, a cylinder of cells

called called pericycle: pericycle: branch or lateral roots form frombranch or lateral roots form from

A root cross sectionA root cross section

2. Stems2. Stems Growth:Growth:

Primary: leaves appear whilePrimary: leaves appear while the the apical meristem elongatesapical meristem elongates

Secondary: differentiation of the Secondary: differentiation of the vascular tissuevascular tissue

vascular tissue types:vascular tissue types: dicotsdicots, vascular bundles (xylem , vascular bundles (xylem

and phloem) are around the and phloem) are around the outside of the stemoutside of the stem

monocotsmonocots, vascular bundles are , vascular bundles are scattered throughoutscattered throughout

places of the stem where places of the stem where leaves form are called leaves form are called nodesnodes

portions of the stem portions of the stem between these leaf between these leaf attachment points are attachment points are called called internodesinternodes

source of economically source of economically important product: important product: woodwood is accumulated xylemis accumulated xylem displays rings based on the displays rings based on the

growth rate differences: growth rate differences: cambiumcambium divides more divides more actively in the spring and actively in the spring and summer summer

bark bark (periderm): (periderm): all of the all of the tissues of a mature stem tissues of a mature stem outside of the vascular outside of the vascular cambium including the cambium including the corkcork

3. Leaves3. Leaves

Growth:Growth: marginal marginal meristems meristems which grow which grow outward and ultimately form outward and ultimately form the the bladeblade (the flattened (the flattened portion) of the leafportion) of the leaf

leaf leaf veinsveins, comprised of , comprised of xylem and phloem, run xylem and phloem, run through the leafthrough the leaf

dicotsdicots, the veins have a net , the veins have a net or or reticulatereticulate venation venation

monocotsmonocots, the veins are , the veins are parallelparallel

Water MovementWater Movement factors:factors:

1.1. initial movement of water into the roots: initial movement of water into the roots: osmosisosmosis1.1. fluid in the xylem contains more solutes than the surroundingsfluid in the xylem contains more solutes than the surroundings

2.2. capillary actioncapillary action adds “pull” to the movement of water up adds “pull” to the movement of water up

3.3. A final “pull” is A final “pull” is transpiration, transpiration, water evaporating from the top (leaf) water evaporating from the top (leaf) of the tube pulls the column of water upof the tube pulls the column of water up

4.4. the column of water does not collapse because water molecules are the column of water does not collapse because water molecules are attracted to each other attracted to each other

5.5. the narrower the diameter of the tube, the more the narrower the diameter of the tube, the more tensile strengthtensile strength, or , or resistance to separation, of the water columnresistance to separation, of the water column

Plant ClassificationPlant Classification

complex multicellular organismscomplex multicellular organisms Autotrophs, feed themselves by photosynthesisAutotrophs, feed themselves by photosynthesis almost exclusively on landalmost exclusively on land dominant organisms on the surface of the earthdominant organisms on the surface of the earth

Plant EvolutionPlant Evolution

ancestor probably: green algae ancestor probably: green algae Four key evolutionary advances:Four key evolutionary advances:

1.1. alternation of generationsalternation of generations, ,

2.2. vascular tissuevascular tissue, transports water and nutrients and , transports water and nutrients and provides supportprovides support

3.3. SeedsSeeds, provide nutrients and protection for the plant , provide nutrients and protection for the plant embryo until it encounters favorable growing embryo until it encounters favorable growing conditionsconditions

4.4. flowersflowers and and fruitsfruits, facilitated fertilization and , facilitated fertilization and dispersal of their seedsdispersal of their seeds

1. Nonvascular Plants1. Nonvascular Plants

size limited size limited materials transported by materials transported by

osmosis and diffusionosmosis and diffusion mossesmosses

2. Seedless Vascular Plants2. Seedless Vascular Plants

fernsferns sporophyte generation is sporophyte generation is

much larger and complexmuch larger and complex

Vascular TissueVascular Tissue

specialized cylindrical specialized cylindrical or elongated cells that or elongated cells that form a network form a network throughout a plantthroughout a plant

3. Vascular, Seed Plants3. Vascular, Seed Plants Seed: crucial adaptation to land to Seed: crucial adaptation to land to protectprotect the the

embryonic plant embryonic plant

produce produce two kinds of gametophytes:two kinds of gametophytes: develop within the sporophytedevelop within the sporophyte

male: male: pollen grainspollen grains female: egg within an female: egg within an ovuleovule

gymnospermsgymnosperms ovules are not completely enclosed ovules are not completely enclosed

angiospermsangiosperms ovules are completely enclosed ovules are completely enclosed

GymnospermsGymnosperms

Conifers, Conifers, seeds in cones seeds in cones most needle-like leavesmost needle-like leaves

Cycads, Cycads, palmlike leavespalmlike leaves

Ginkgo, Ginkgo, fan-shaped leavesfan-shaped leaves

Angiosperms: flowersAngiosperms: flowers

90% all living plants90% all living plants Embryos store food Embryos store food

reserves in seed leaves reserves in seed leaves or or cotyledonscotyledons

monocotsmonocots have one have one cotyledoncotyledon

dicotsdicots have two have two cotyledonscotyledons

Angiosperm ReproductionAngiosperm Reproduction

1.1. sexualsexual

2.2. AsexualAsexual

Asexual, Asexual, vegetative vegetative reproductionreproduction

new individuals are cloned new individuals are cloned from parts of the parentfrom parts of the parent

Samples: Samples: RunnersRunners, , stems growing stems growing

along the soil along the soil RhizomesRhizomes, , underground underground

horizontal stems horizontal stems

Sexual reproduction: alternation of generationsSexual reproduction: alternation of generations male gametophytes: male gametophytes: pollen grainspollen grains female gametophyte: female gametophyte: embryo sacembryo sac

FlowersFlowers

Base: Base: receptaclereceptacle four concentric circlesfour concentric circles::

1. 1. Sepals, Sepals, protect protect

2. Petals2. Petals, , attract pollinatorsattract pollinators

3.3. male parts:male parts: stamens stamens, , anther anther with the with the pollen grainspollen grains

4.4. female parts:female parts: ovulesovules in the in the bulging base called bulging base called ovary, ovary, a a stalk stalk style, style, sticky tip sticky tip stigmastigma to to receive the pollenreceive the pollen

different kinds of flowers: because insects and different kinds of flowers: because insects and plants plants coevolved coevolved

insects specialize in visiting particular kinds of flowersinsects specialize in visiting particular kinds of flowers Birds also pollinate some flowers, especially red onesBirds also pollinate some flowers, especially red ones

Eggs Eggs develop in the develop in the ovulesovules each ovule contains a each ovule contains a megaspore mother cellmegaspore mother cell

that undergoes meiosis to produce four haploid that undergoes meiosis to produce four haploid megaspores, only one survives to undergo megaspores, only one survives to undergo repeated mitotic divisions that produce eight repeated mitotic divisions that produce eight haploid nucleihaploid nuclei

Formation of pollen and eggFormation of pollen and egg

PollinationPollination process by which pollen is transferred from the process by which pollen is transferred from the

anther to the stigmaanther to the stigma gymnospermsgymnosperms, pollen is dispersed by , pollen is dispersed by wind; wind; species species

must grow close, flowers are small, green, and must grow close, flowers are small, green, and odorlessodorless

angiospermsangiosperms use use animalsanimals to carry pollen from flower to carry pollen from flower to flower and are rewarded with food; e.g.,to flower and are rewarded with food; e.g., nectarnectar

Pollen grainsPollen grains adhere to the surface of the adhere to the surface of the stigma and begin to grow a stigma and begin to grow a pollen tubepollen tube until it until it reaches the ovule in the ovary, entry to the reaches the ovule in the ovary, entry to the embryo sacembryo sac

it releases twoit releases two sperm cells sperm cells: : double double fertilizationfertilization

one sperm one sperm fertilizesfertilizes the egg the egg the other sperm goes on to form the other sperm goes on to form endospermendosperm

SeedSeed

three partsthree parts1.1. embryoembryo

2.2. endospermendosperm, a source , a source for food for the for food for the developing embryo developing embryo (cotyledons)(cotyledons)

3.3. a drought-resistant a drought-resistant protective protective covercover

Seeds improved the adaptation of plants to Seeds improved the adaptation of plants to living in land:living in land:

1.1. Dispersal Dispersal into new habitatsinto new habitats

2.2. Dormancy and Germination, Dormancy and Germination, plants postpone plants postpone development until conditions are favorabledevelopment until conditions are favorable

3.3. Nourishment; Nourishment; provisions the seed during the provisions the seed during the critical period just after germinationcritical period just after germination

FruitsFruits

Is a Is a mature ripened ovarymature ripened ovary containing fertilized seeds containing fertilized seeds angiosperms use fruits to have animals aid in the dispersal of angiosperms use fruits to have animals aid in the dispersal of

seeds; although eaten the seeds are resistant to chewing and seeds; although eaten the seeds are resistant to chewing and digestion passing out with the feces and ready to germinatedigestion passing out with the feces and ready to germinate

Types of fruits and common modes Types of fruits and common modes of dispersionof dispersion

Practice questionsPractice questions1. 1. Growth in vascular plants is regulated and coordinated by:Growth in vascular plants is regulated and coordinated by:A)A) photosynthetic tissuephotosynthetic tissueB)B) root tissueroot tissueC)C) meristematic tissuemeristematic tissue

2. 2. In vascular plants, phloem tissue transports _______In vascular plants, phloem tissue transports _______

3. 3. In stems, the tissue responsible for secondary growth is the:In stems, the tissue responsible for secondary growth is the:A)A) CollenchymaCollenchymaB)B) PithPithC)C) CambiumCambiumD)D) cortexcortex

4. 4. One difference between monocot/dicot plant stems is the:One difference between monocot/dicot plant stems is the:A)A) absence of buds in monocotsabsence of buds in monocotsB)B) organization of vascular tissueorganization of vascular tissueC)C) presence of guard cellspresence of guard cells

5. 5. Which of the following is not a process that directly assists Which of the following is not a process that directly assists in water movement from the roots to the leaves?in water movement from the roots to the leaves?

A)A) photosynthesis photosynthesis B)B) root osmotic pressure root osmotic pressure C)C) capillary action capillary action D)D) transpirationtranspiration

6. 6. Sexual reproduction in angiosperms requires male _______Sexual reproduction in angiosperms requires male _______

7. The flower shape, scent, color, nectar in the flowers of some 7. The flower shape, scent, color, nectar in the flowers of some angiosperms are related to the plant's __angiosperms are related to the plant's __

9. 9. Fruit forms from a flower's: Fruit forms from a flower's: A)A) OvaryOvary B) B) sepalssepals C) C) carpelscarpels D) D) stigmastigma

10. 10. Which of the following structures does not give the plants an Which of the following structures does not give the plants an evolutionary advantage?evolutionary advantage?

A)A)chloroplasts chloroplasts B)B)vascular tissue vascular tissue C)C)seeds seeds D)D)flowersflowers

11. 11. Mosses do not reach a large size because ------------Mosses do not reach a large size because ------------

12. 12. One characteristic that separates ferns from more complex vascular One characteristic that separates ferns from more complex vascular plants is that ferns do not have ---------plants is that ferns do not have ---------

13. 13. What separates the gymnosperms from the rest of the vascular plants is:What separates the gymnosperms from the rest of the vascular plants is:A)A) a vascular systema vascular systemB)B) ovules completely covered ovules completely covered C)C) ovules not completely covered ovules not completely covered D)D) fruits and flowersfruits and flowers

14. 14. What separates the angiosperms from the rest of the vascular plants is:What separates the angiosperms from the rest of the vascular plants is:A)A) a vascular systema vascular systemB)B) ovules completely covered ovules completely covered C)C) ovules not completely covered by the sporophyteovules not completely covered by the sporophyteD)D) fruits and flowersfruits and flowers

15. 15. Flower shape and color can be linked to the process of -------------Flower shape and color can be linked to the process of -------------

16. 16. If the seeds of a plant are encased in a fleshy fruit, then the most likely form of If the seeds of a plant are encased in a fleshy fruit, then the most likely form of dispersal is:dispersal is:

A)A) to attach to an animal's fur or skinto attach to an animal's fur or skinB)B) WindWindC)C) an animal's digestive system and processesan animal's digestive system and processesD)D) waterwater