Taproots	are large and fleshy in appearance, grow deep into the ground to search for food, are able to store food, which is particularly necessary for perennial plants during periods of dormancy, are mostly found in plants with two seed-leaves (dicots)
Fibrous roots	lie close to the surface of the soil, collect precipitation before it sinks deep into the ground, can often be found growing side by side with taproots: the two types of root combine efforts to maximize efficiency. are mostly found in plants with one seed-leaf (monocots)
Adventitious roots	develop to help the plant climb: for example, ivies help develop modified underground stems, such as bulbs are common in both dicots and monocots

Shoot system - p. 723

· Plant anatomy

· Stem Anatomy

· Tissues and Organ of Herbaceous Plants

· Comparison: Woody stem, herbaceous dicot and herbaceous monocot

§ Figure 35.2 Morphology of a flowering plant p. 722

§ What is a stem?

· Nodes

· Internodes

· Axillary bud

· Terminal bud

· Apical Dominance

· Some plants have modified shoots with diverse functions. Briefly describe the modified shoots below. Figure 35.4 page 723

o Stolons (above ground)

o Rhizomes (below ground)

o Tubers

o Bulbs

STEMS THAT ARE MODIFIED Many plants have stems that are modified to protect the plant, conserve water, spread by growing horizontally above or below the ground, or store water or food.
Thorns rose .	Leaf-Like Stems (cladophyll) prickly pear
Underground Stems (rhizome) sansavieria .	Horizontal Stems (runners and stolons) grass
Flat Plate-Like Stems (bulb) onion	Storage Stems (tuber) Irish potato

Leaves p. 723

· Leaf Anatomy (external)

· Blade

· Petiole

· Know the differences between monocot and dicot

· Modified Leaves p. 724 Figure 35.6

Modified Leaves Some leaves have many unusual shapes and sizes. This allows them to adapt to protect the plant, to store food, or to adapt to the environment in which they grow.
Scale Leaf cedar or juniper ..	Needle pine .
Succulent storage leaf sedum .	Food storage leaf onion bulb
Spine prickly pear cactus .	Tendril grape ivy

· Figure 35.5 Leaf types: Simple vs Compound p. 724

· Figure 35.19 Leaf Anatomy p. 734 be able to identify structures. Also, note the stoma and guard cells

· Stomata and guard cells p. 734

· mesophyll

· Transpiration

Plant organs are composed of three tissue systems: dermal, vascular, and ground p. 724

· p. 725 Figure 35.7 The Three Tissue Systems

· Dermal Tissue

· Epidermis

§ cuticle

· Vascular tissue

· Xylem- transports water/dissolved mineral

§ Primary xylem

§ tracheids

§ vessel elements

§ p. 725 Figure 35.8 Water-conducting cells of xylem

§ What is meant by “functional maturity”?

§ Pits

§ Xylem vessels

§ Review Transport of Xylem Sap p. 756, Chapter 36. We discussed this earlier in the year

· Phloem -transports food (sucrose or other organic molecules) made in leaves to roots and nonphotosynthetic areas

§ Sieve tube Members

§ Sieve plates

§ Companion cells

§ p. 726 Figure 35.9 Food conducting cells

· Ground tissue (functions/examples)

Plant tissues are composed of three basic cell types: parenchyma, collenchyma, and sclerenchyma p. 726

· Parenchyma cells - have flexible primary walls, contain a large central vacuole; the least specialized of plant cells. Performs photosynthesis, stores organic compounds and performs other metabolic activities. This is the typical plant cell studied in biology

· Collenchyma cells- stronger walls; provides support for young plants.

· Sclerenchyma cells- very strong secondary cell walls, fortified with lignin. Dead a functional maturity provides support for the plant.

The Process of Plant Growth and Development p. 729

· Growth

· Development

Meristems generate cells for new organs throughout the lifetime of a plant p. 729

· Annuals

· Biennials

· Perennials

· Meristems

· Apical Meristems

§ Primary growth

· Secondary growth

§ Lateral meristems

· Vascular cambium- produces secondary phloem and xylem

· Bark refers to all tissues external to the vascular cambium

§ Cork cambium tough covering for stems and roots

§ Figure 35.23 Anatomy of a tree trunk p. 737

· p. 729 Figure 35.12 Locations of major meristems

· p. 730 Figure 35.13 Morphology of a winter twig

Primary growth: Apical meristems extend roots and shoots by giving rise to the primary plant body p. 730

· Primary plant body

Primary Growth of Roots

· Root cap

· The Root Zones

· Zone of cell division- area of actively dividing cells (apical meristem) produces primary meristems and replaces root cap as needed. This zone contains apical and primary meristems

· Zone of elongation- area where the cells elongate

· Zone of maturation- the cells differentiate and grow becoming functionally mature.

· p. 730 Figure 35.14 Primary growth of a root

· p. 731 Figure 35.15 Organization of primary tissues in young roots (Monocot Root and Dicot Root comparison)

Primary Tissues of Roots

p. 731

· Stele- central cylinder of the root. Xylem and phloem will develop here. The outer most layer of the stele is called the pericycle. The root actually originates from the pericycle, deep inside the root, and grows outward.

· Ground tissue cells- store food and actively uptake minerals that enter the roots

· Endodermis- a single layer of cells separating the cortex and the stele. Functions as a selective barrier regulating minerals moving from soil into the vascular tissues of the stele.

Primary Growth of Shoots p. 732

· Apical meristems produce primary meristems (just like in the roots). This eventually gives rise to Leaves, axillary buds, buds

· Axillary buds can become new stems.

Primary Tissues of Stems p. 733

· p. 733 Figure 35.18 Organization of primary tissues in young stems (monocot and dicot comparison)

· Vascular bundles- strands of vascular tissues running the length of the stem

· Vascular bundles are surrounded by ground tissue. The phloem is arranged so that it faces outward and the xylem faces inward. Dicot stems have vascular bundles arranged in a ring whereas monocot stems have scattered bundles throughout the stem.

Tissues of Organization of Leaves p. 734

· Figure 35.19 Leaf Anatomy. Need to know

Secondary growth: Lateral meristems add girth by producing secondary vascular tissue and periderm p. 734

· Secondary growth- adds girth to stems and roots

· Vascular cambium

· Cork cambium

Vascular Cambium and the Production of Secondary Vascular Tissue p. 735

· p. 737 Figure 35.23 Anatomy of a tree trunk

· The vascular cambium forms a ring around the length of the plant.

· It produces secondary xylem to its interior and secondary phloem to the exterior. Layers (girth) are added to the plant as more secondary xylem and phloem are produced over the years.

· Secondary xylem accumulates forming wood. Wood is dead at functional maturity providing strength and hardness. Annual tree rings form each year as a new layer of secondary xylem is produced.

o Heartwood (center portion of wood) is older and no longer functions in water transport.

o Sapwood is still functional in the transport of water and minerals (xylem sap) and is located to the outside of the heartwood.

· Secondary phloem is functional in sugar transport when it is young, after death it eventually will be pushed outward and sloughed off by the plant.

o To the outside of the secondary phloem is the cork cambium.

§ Cork cambium produces the cork When cork cells mature they produced cuticle then die…forming the bark

§ Specialized regions along the bark, called lenticels, form allowing gas exchange to occur.

§ Periderm= Cork Cambium + Cork

§ Bark= Periderm + Secondary Phloem

Growth, morphogenesis, and differentiation produce the plant body p. 739

· Morphogenesis- development of body form and organization

· Differentiation- generation of cellular diversity…cells grow, becoming specialized.

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