Plant Biology - Tissues

DermalVascularGround

Plant Biology Part 2 - Tissues

Plant Tissue

Dermal Tissue

Vascular Tissue

Ground Tissue

Dermal Tissue

Outermost layer of a plantEpidermis: thin layer of cells that

covers the surface of leaf, stem and root

Periderm tissue: bark on stem and large roots of woody plants (replaces the epidermis)

Dermal Tissue

Some dermal tissues have unique functions

Root cells: root hairs (long extensions)

Leaf cells: produce cuticle

Vascular Tissue

Plant circulatory systemVessels that connect roots to leavesTransports water, dissolved

minerals, and sugars throughout plant, providing cells with materials to carry out life functions

Two types: Xylem Phloem

Vascular Tissue: Xylem made up of long hollow tubes

formed by non-living cell walls (left over from plant cells that have died)

transports water and dissolved minerals upwards from roots

Vascular Tissue: Phloem Made up of elongated cells that are

living Transports:

solutions of sugars (food) Dissolved nutrients Hormones

Bi-directional movement of materials downward to roots upward to leaves

Vascular Bundle

Plant Sugars

Starch is NOT soluble in water Starch can be broken down into

sucrose Sucrose IS soluble in water Sucrose is transported through the

phloem to the plant parts that require it Sucrose can be broken down into

glucose Glucose is used in cellular respiration to

make cellular energy

Starch sucrose glucose

Early Spring Trees need energy to

grow leaves Energy comes from

cellular respiration of glucose:Glucose + oxygen carbon dioxide + water + energy

Glucose can be obtained by: Photosynthesis - but

spring trees don’t have any leaves to do photosynthesis

Converting it from starch

Early Spring Starch

Stored in the roots Insoluble in water so it cannot be transported

through phloem Convert to sucrose

Sucrose Soluble in water Transport from root to tree bud through phloem Convert to glucose in tree bud

Glucose Use in cellular respiration Converted to cellular energy needed to grow leaves

Tree Sap

Starch Sucrose GlucoseRoots Stem LeavesStorage Transport Photosynthesi

s

Plant Sugars

SugarSolubilityin water

Location Function

Starch No Root Storage

Sucrose Yes Stem Transport

Glucose Yes Leaf Photosynthesis

Summer

Once leaves have grown, they can perform photosynthesis to produce their own glucose

Glucose is converted to sucrose and transported through the phloem to the roots

Sucrose is converted to starch in the roots for storage

Glucose(leaves)

Sucrose(stem)

Starch(roots)

Winter storage

Summer and Fall

Summer and Fall

Spring

Spring

Sugar Movement through Phloem

http://www.nuscentscandle.com/blog/wp-content/uploads/tree-sap.jpg

Cells in the Root Cells in the root have no chloroplasts and are not

exposed to sunlight so they can not undergo photosynthesis to make their own food

Root cells must perform cellular respiration to obtain cellular energy

Glucose + oxygen carbon dioxide + water + energy

Glucose comes from the starch stored in the root Oxygen is absorbed through the soil

Plants at Night At night, plants are not exposed to sunlight so

they can not undergo photosynthesis to make their own food

Plants must perform cellular respiration at night to obtain cellular energy

Glucose + oxygen carbon dioxide + water + energy

Glucose comes from the starch stored in chloroplast and vacuoles of most plant cells

Stomata opens at night to allow oxygen to enter the leaves and carbon dioxide to exit

Ground Tissue

Filler tissue in between the dermal and vascular tissue

Variety of processes depending on where it is in the plant

In leaf: palisade and spongy mesophyll cells

3 Tissue Types in Leaf

3 Tissue Types in Stem

http://bio1151b.nicerweb.net/Locked/media/ch35/35_16StemTissueLayers.jpg

3 Tissue Types in Root

http://bio1151b.nicerweb.net/Locked/media/ch35/35_12PrimaryRootGrowth.jpg

3 Tissue Types in Roothttp://bio1151b.nicerweb.net/Locked/media/ch35/growth-root_tissues.html

3 Tissue Types in 3 Plant Parts

http://bio1151b.nicerweb.net/Locked/media/ch35/tissue_system.html

3 Tissue Types in 3 Plant Parts

http://158.108.17.142/museum/MotherEarth/overview.jpg