ROOTS 26.2. Function Anchor Absorb – H 2 O and minerals are “pulled” up through transpiration...

ROOTS26.2

FunctionAnchor

Absorb – H2O and minerals are “pulled” up through transpiration (H20 evaporates from leaves and pulls water from roots in the process)

GENERAL TYPES

Fibrous

Tap

ADAPTATIONSAdventitious

Aerial

prop

Air

Storage

REGIONS OF DEVELOPMENT

Region of Cell Division – “Apical Meristem”

Region of cell division

Root Cap

REGIONS OF DEVELOPMENT…

Region of Elongation – gives length to root

Region of Cell Division

Region of Elongation

REGIONS OF DEVELOPMENT…

Region of Cell Maturation – differentiate into specialized tissues – “Primary Root Stucture)

Region of Cell Division

Region of Elongation

Region of Maturation

Primary Root Structure1st tissue to develop from Region of MaturationEpidermis- outermost, absorbs, protects, root hairs derived from hereCortex – storage, controls flow of water

Primary Root Structure…

Vascular Cylinder

Pericycle – 2ndary growth from here

Xylem – carries water

Phloem – carries sugar

Epidermis

Cortex

Pericycle

Xylem

Phloem

Secondary Growth

Root hairs

Lateral roots

Types of Root Growth

Primary – growth in length

Secondary – growth in diameter

Arrangement of Vascular tissue

Flowering plants are divided into two groups based on structural differences

Monocots

Dicots

Monocot Root Tissue Arrangement

Dicot Root Arrangement

STEMS23.3

FUNCTION

Support

Conduct water and food

Storage

photosynthesishttp://www.youtube.com/watch?v=w6f2BiFiXiM&feature=related

STRUCTUREEpidermisCambium – mitotic; makes new xylem and phloemPith, Cortex – storageBark – dead cells,protects from water lossVascular tissue – xylem and phloem

Epidermis

Cortex

Cambium

Phloem

Xylem

Pith

Arrangement of Vascular Tissue

Monocot – Vascular tissue is scattered bundles

Dicots – Vascular tissue is arranged in a ring patterm

monocot

dicot

Stem Growth

Meristem - located on tips (growth in height - primary) and on sides (growth of branches - secondary)

Cambium – growth in diameter – secondary; forms tree rings.

Types of StemsWoody

Dead xylem cells form wood; adds strengthGrow in width each yearVascular tissue arranged in ringsBark protectsPerennial – grow more than one season

Type of Stem…Herbaceous

Soft, fleshyUsually green; no barkNot much secondary growth (width)Vascular tissue is scattered.Annuals – only grow one season

Stem Adaptations

Stolons/rhizomes – runners; cause vegetative propagation

Tubers – underground stems; storage; potato

Bulbs/corms – underground stems with fleshy leaves; onions, tulips, garlic

LEAVES23.4

Function

Photosynthesis

Transpiration – pulling water up from the roots and out the leaves

Structure

Epidermis

Upper – covered by cuticle

Lower – contains stoma with guard cells

Cont.

Palisade layer – many chloroplasts

Mesophyll – many air spaces

Vascular bundle – “veins”

VEIN

PalisadeLayer

MesophyllStomata

Epidermis with cuticle

External StructuresPetiole – structure that attached leaf to stemBlade – thin, flat area of leaf; different sizes, shapes & arrangementMid rib – main vein Leaf margin – edge of leaf

Venation in Monocots and Dicots

Monocots – parallel leaf venation

Dicots – netted venation

Pop Quiz

Adaptations in leaves

http://www.youtube.com/watch?v=ktIGVtKdgwo&feature=fvsr

Flowers, Fruits & SeedsCh. 24

Angiosperms

reproduce using flowers.

Flowering Plants have:Monocot Dicot

FlowersMultiples of 3 Multiples of 4 or 5

1

23

4

5

6

23 4

5

6

7

18

6

Flowers

Composed of modified leaves

Sepals – usually green; enclose bud

Petals – brightly colored; just inside sepals

Stamen – male reproductive organ• Filament - stalk• Anther – produces pollen (male gamete)

Carpel (pistil) – female reproductive organ • Stigma- sticky; pollen attaches here• Style – narrow stalk• Ovary – contains ovules

Anther

filament

Parts of a Typical Flower

StamenMale partof flower

AntherFilament

Parts of a Typical Flower

PistilFemale part

of flower(Sounds like “Pigtail”)

Stigma

Style

Ovary

Plant ReproductionPlants can reproduce asexually by

vegetative propagation.

Stems

PlantletsRoots

Stems, plantlets and roots can become a new plant.

Plant ReproductionPlants can reproduce asexually by

plant propagation.

CuttingsGrafting & Budding

A “cut” from a plant cangrow roots when put in soil. Two plants are attached

to form one plant.

Angiosperm Life CyclePollination – transfer of pollen from anther to stigma of carpel

Often dependent on pollinators

Pollen grows a tube through which sperm nuclei travel

Fertilization –

sperm nuclei fuse with ovule inside

produce a seed

Ovary ripens into a fruit

Fruits – ripened ovary ; type determined by structure of ovary and ovules

DryNuts

FleshyDrupes - applePomes - peachBerriesHesperidium - orangePepo - cucumberAggregate - raspberry

Seed Dispersal

Animal

Wind

Water

Seed Germination

Timing controlled by climate (moisture, temperature, etc.)

Endosperm (food source) swells with moisture and cracks open seed coat

Root emerges first

Cotyledons emerge secondMonocot – one seed leaf

Dicot – two seed leaves

Plant Growth

Controlled by hormones (auxins)

Cause “tropisms”

Gravitropism

Thigmotropism

phototropism