Plant Cells and Tissues Ch 23

Plant Tissue: Label and list function (s) :Epidermis, stoma, cuticle,mesophyll, vascular bundle, xylem, phloem, guard cells

Plant Tissues 1. Dermal Tissue (epidermis)

2. Ground Tissue3. Vascular Tissue

1. EpidermisFlattened cells

Outer coveringProtects body

Cuticle; waxy (not on roots)Prevent water loss

Epidermis:DRAW AND LABELGUARD CELLS & STOMATA

Guard Cells Daytime-fill with

water and Stomata open Night, guard cells

_______, and Stomata ______

Epidermis

Stomata-openings Leaves (mostly

bottom)& stems Control water

loss Gas Exchange Controlled by

Guard Cells

Epidermis Root hairs-on root

epidermal cells Enhance water &

mineral absorption

2. Vascular Tissue A) Xylem-Function: H2O &

Mineral transport from root to leaves.

B) Phloem- Function: Sugar &

other organic material transport throughout plant body

3. Ground TissueMost of the plant tissue.

Functions: photosynthesis, storage

Surrounds vascular tissue

Plant GrowthMeristems—Regions of

actively dividing cells.Rootshoot

Plant Growth

Figure 35.11

This year’s growth(one year old)

Last year’s growth(two years old)

Growth of twoyears ago (threeyears old)

One-year-old sidebranch formedfrom axillary budnear shoot apex

Scars left by terminalbud scales of previouswinters

Leaf scar

Leaf scar

Stem

Leaf scar

Bud scale

Axillary buds

Internode

Node

Terminal bud

Primary

Secondary

Wood and bark

How Vascular tissue is Arranged in stems

Dicot stem

Two Classes of Angiosperms (Anthophyta) ( p. 596)Cotyledons: seed leafMonocots—1

65, 000 speciesGrasses, lily, palms

Dicots—2185,000 speciesTomatoe, oak, parsley

Monocots Dicots# of Cotyledons

Leaf Vein Arrangement

How flower parts are arranged

Arrangement of Vascular Tissue

# of Cotyledons

Leaf Vein Arrangement

How flower parts are arranged

Arrangement of Vascular Tissue

Cotyledon

Structure in the embryo of a seed plant that may form a ‘leaf’ after germination and is commonly known as a seed leaf. The number of cotyledons present in an embryo is an important character in the classification of flowering plants (angiosperms).

Monocotyledons (such as grasses, palms, and lilies) have a single cotyledon, whereas dicotyledons (the majority of plant species) have two. In seeds that also contain endosperm (nutritive tissue), the cotyledons are thin, but where they are the primary food-storing tissue, as in peas and beans, they may be quite large. After germination the cotyledons either remain below ground (hypogeal) or, more commonly, spread out above soil level (epigeal) and become the first green leaves. In gymnosperms there may be up to a dozen cotyledons within each seed.

http://www.ucmp.berkeley.edu/glossary/gloss8/monocotdicot.html

Plant Body *Roots

*Shoots (stems, leaves)

Figure 35.2

Reproductive shoot (flower)

Terminal bud

NodeInternode

Terminalbud

Vegetativeshoot

BladePetiole

Stem

Leaf

Taproot

Lateral roots Rootsystem

Shootsystem

Axillarybud

Plant Body

Plant Body--Roots1.First Part to Grow

Positive Gravitropism

Roots: FunctionAnchorAbsorb water, mineralsStore Nutrients

Prop Roots Grow Above

groundHelp Support

Example: corn,mangrove

Aerial RootsFormed in and exposed to airOrchidsIvyRainforest trees

Root Anatomy Root Cap Root Tip Root Hairs

Plant Body-Shoots Above ground parts

1. Stems Supports leaves, flowers, fruit Contain Vascular Tissue

2. Leaves Photosynthesis Thin & Flat (high SA:V) Veins ( Bundles)

Stomata-open & close

Seeds

Fruits vary from hard and woody to soft. They can have one to multiple seeds, and hard or soft seeds. Some seeds are readily eaten (e.g. peas, nuts), while some are not (e.g. cherry pits, apple seeds).

    Two peanut seeds in the hard ovary (left);

apple seeds in the fleshy fruit, composed partly of flower petals and sepals (right).

Cacti adaptations Cacti depend on chlorophyll in the outer tissue of their skin

and stems to conduct photosynthesis for the manufacture of food. Spines protect the plant from animals, shade the plant from the sun and also collect moisture. Extensive shallow root systems are usually radial, allowing for the quick acquisition of large quantities of water when it rains. Because they store water in the core of both stems and roots, cacti are well-suited to dry climates and can survive years of drought on the water collected from a single rainfall.

Many other desert trees and shrubs have also adapted by eliminating leaves -- replacing them with thorns, not spines -- or by greatly reducing leaf size to eliminate transpiration. Such plants also usually have smooth, green bark on stems and trunks serving to both produce food and seal in moisture, such as the Paloverde. Some plants produce ephemeral leaves during the brief rainy season to help increase transpiration and photosynthesis. Sometimes these leaves only last for one day.