Plants Structure, Growth, & Development - PowerPoint Presentation

Slide1

Plants Structure, Growth, & DevelopmentSlide2

https://www.youtube.com/watch?v=DGpPHrLF-5M

Plant Structure IntroductionSlide3

Parts of a SeedSlide4

SeedEach seed contains a plant embryo

Each seed also contains food for the embryo

A tough outer case protects the embryo, known as a seed coatSlide5

Parts of a SeedExternal seed coat Developing plant embryo

Stored food called endospermSlide6

Seed Dispersal

The main function of the

fruit

is to disperse the

seeds

Four

T

ypes:

Self dispersal

Wind

dispersal

Water

dispersal

Animal

dispersalSlide7

Seed DormancyEnsures that

the seed will germinate only when there are optimal

conditions

Plants stay dormant until the

right environmental conditionsSlide8

Seed GerminationSeeds do not always germinate right away; can

wait for

long periods of

time to

grow

Seed need

water, nutrients and the right temperature to

growSlide9

Order of Growth

embryonic

root, embryonic shoot,

leavesSlide10

Seed LabelingYou have 5 minutes to complete the diagramSlide11
Slide12

https://www.youtube.com/watch?v=pQYJ2PSDu3A

Lima Bean DissectionSlide13

Plant Growth & TissueSlide14

MeristemsPlant cells that contain stem cells

Apical

meristems

Elongate

shoots and roots through primary growth

L

ocated

at the tips of roots and in the buds of

shoots

Lateral meristems

Add

thickness

of stems and roots

through secondary growthSlide15

Tissue SystemsDermal tissue system

Consists of the

epidermis

Ground tissue

V

arious

cells specialized

for:

Storage

Photosynthesis

S

upportSlide16

Three Tissue Systems: Dermal

, Vascular,

&

Ground

Each plant

organ has…

Dermal

, vascular, and ground tissues

Dermal

tissue

Ground

tissue

Vascular

tissueSlide17

Vascular TissueVascular

tissue system

Transport

of materials between roots and shoots

Xylem

Transports

water

upward

from roots into the

shoots

Phloem

Transports

nutrients

from where they are made to where they are neededSlide18

Vascular TissueSlide19

RootsSlide20

RootsRoot Structure

Apical meristem

N

ew cells along roots & stem; differentiate into other tissue

Root Cap

P

rotects root as it grows

Key role in water & mineral transportSlide21

RootsA

nchor

plants firmly in the

ground

A

bsorb

water and minerals

from

the

soil

Some roots

can

be

used

to grow a new plantSlide22

Types RootsFibrous roots

Multiple smaller roots

Tap roots

L

arge main central

rootSlide23

RootsAbsorption of water &

minerals near root tips

Large numbers of tiny root hairs increase the surface area of the root

Minerals use active

transportSlide24

Roots LabelingYou have 5 minutes to complete your roots diagramSlide25
Slide26

StemsSlide27

StemsStructure

Produce leaves, branches, and flowers

Hold leaves up

Transport substance between roots and leaves

Transport systemSlide28

StemsXylem and phloem

M

ajor tubule systems

Transport water

&

nutrients

Nodes

Attachment for leaves

Internodes = stem between nodes

Petiole

“Stem” of the leafSlide29

Types of Stems

Woody

Thick cell walls

Trees, shrubs, and vines

Herbaceous

Supported by hydrostatic pressure (turgor)

Dandelions, zinnias, petunias

Slide30

Underground StemsTuborsUsed to store food for the plantBulbsAllows the plant to be dormant

with cold temperature

Rhizome

H

orizontal

underground

stem = produces shoot and 

root systems

of a new

plantSlide31

StemsLenticles

Pore in the stem

providing

direct

gas exchange

Buds

U

ndeveloped

shoot from which embryonic leaves or flower parts ariseSlide32

Transport in PlantsCapillary action

Tendency

of water to rise in a thin

tube

Adhesion & cohesionSlide33

LeavesSlide34

LeavesSight of photosynthesis

Anatomy

Cuticle – covers and protects leaf

Blade

– thin flattened section

Petiole – stalk that attaches stem to blade

Covered by epidermis and cuticle

Create water proof barrierSlide35

Mesophyll & Stomata

Mesophyll

– site of photosynthesis

Palisade mesophyll – absorb light

Spongy mesophyll

– air space for gas diffusion

Stomata – pores on the underside of the leaf

CO2 enters

 O2 + H2O

exit

Most active during the day

Guard Cells –

open and close stomataSlide36

Leaf AdaptationsExcess of

Sunlight

Thick cuticle

Small/narrow leaves

Limited Sunlight

Thin cuticle

Large/broad leavesSlide37

Transport & TropismsSlide38

Transport in PlantsTranspiration

Osmotic pressure moves water out of vascular tissue

This pulls water up from the stem to the leaves

Affected by heat, humidity, windSlide39

GravityResponse to gravity is

gravitropism

Roots show positive

gravitropism

Stems show negative

gravitropismSlide40

HydrotropismRoots grow toward water (positive)Slide41

Thigmotropism

Growth in response to touch

Plant

grows toward

(+) or

away from (-) pressure

Vines

and other climbing

plantsSlide42

Thermotropism

Plant response to temperature

‘

HEAT’Slide43

Phototropism

Plants grow toward a

source

of light

Tropisms

https://www.youtube.com/watch?v=pCFstSMvAMISlide44

Plant HormonesSlide45

Plant Hormones & Tropisms

Hormones

Chemical

signals that coordinate growth, development, and responses to

stimuli

Tropisms

are often caused by hormonesSlide46

Auxin

Any

chemical substance that promotes cell elongation

(growth) in

different target

tissues

Formation & branching

of

rootsSlide47

GibberellinsStem

elongation (growth)

Fruit growth

Seed germinationSlide48

CytokininsStimulate

cell division

Found in actively

growing tissues Slide49

Ethylene“Aging” hormone

Causes fruits to ripen