7/7/2016SB3A and SB3C1 Plants: Roots, Stems, Leaves and Flowers Chapter 23

7/7/2016SB3A and SB3C2 Standard SB3A and SB3B Students will derive the relationship between single-celled and multi-celled organisms and the increasing complexity of systems. A. Explain the cycling of energy through the process of photosynthesis and respiration. B. Compare how structure and function vary between the six kingdoms.

Parenchyma Cells Stores starch, oils, and water Heals wounds to plant Thin flexible walls 7/7/2016SB3A and SB3C3

Collenchyma cells Provide support growing plants Strong and flexible Ex: Celery strings Unevenly thick cell walls 7/7/2016SB3A and SB3C4

Sclerenchyma cells Strongest of the plant cells Second cell wall has lignin Die at maturity Used to make linen and rope 7/7/2016SB3A and SB3C5

7/7/2016SB3A and SB3C6 Plant Organs Roots Stems Leaves Flowers

Plant organs composition Dermal tissue (covers outside of plant)  Protects the plant  Secretes cuticle  Forms outer bark of trees Ground tissue (inside of plant)  Provides support  Stores minerals in roots and stems  Common parenchyma cells Vascular tissue (transport system) 7/7/2016SB3A and SB3C7

Roots Functions:  Anchors Plant  Absorbs water and minerals  Stores photosynthetic products  Root hairs aid in absorption 7/7/2016SB3A and SB3C8

Roots Primary Root  First root to grow out of the seed Taproot  Main root  Anchors plant  Food and water storage  Ex: carrot Fibrous Roots  Roots that spread out  Anchors plant  Rapid water storage 7/7/2016SB3A and SB3C9

7/7/2016SB3A and SB3C10 Root Structure 3 parts  Apical Meristem Place of cell division Root cap over meristem to protect it  Region of Elongation New cells grow larger  Region of Maturation New cells specialize into the type of cell they will become (ex: xylem, phloem)

root cap Root cap covers the tip.

apical meristem Apical meristem is an area of growth

Vascular cylinder contains xylem and phloem vascular cylinder

7/7/2016SB3A and SB3C14 Root Structure Cross Section of Root  Outer surface = Dermal Tissue Root hairs found here, absorb water  Inner Area = Cortex Cells where water/minerals flow through the root to the center  Endodermis = Surrounds the innermost area Controlled by the Casparian Strip  Semi permeable, controls what gets into the center of the cell  Vascular Cylinder = Inner most area Xylem and phloem found here

7/7/2016SB3A and SB3C15 Epidermis Ground tissue (cortex) Vascular Cylinder Cross Section of Plant Root (magnification: 40x) Ground tissue (cortex) Epidermis Endodermis Vascular cylinder Root hairs Phloem Xylem Apical meristem Root cap Zone of maturation Zone of elongation Endodermis The Structure of a Root

Stems Function  Support leaves and flowers  Transport Xylem and Phloem  Grow underground for storage  Grow into new plants 7/7/2016SB3A and SB3C16

Stems Apical Meristem (primary growth)  Found at tips of stems  Makes plant grow taller Lateral Meristem (secondary growth)  Found at sides of stem  Makes plant grown in circumference 7/7/2016SB3A and SB3C17

Stems Modified Stems  Rhizomes Food storage Asexual reproduction  Tubers Food storage  Bulbs Food storage 7/7/2016SB3A and SB3C18

7/7/2016SB3A and SB3C19 Stems Annual Rings  Vascular bundles (bundles of xylem and phloem) in the stem Spring Time – lots of growth, light colored rings Summer Time – some growth, dark color  Age trees by counting the rings one light, one dark = 1 year

7/7/2016SB3A and SB3C20 Tree Rings

Leaves Purpose: Photosynthesis Many types of leaves  Generally thin and flat  Tendrils  Spines Types of tissue  Palisade mesophyll absorbs sunlight  Spongy mesophyll connects to stomata 7/7/2016SB3A and SB3C21

7/7/2016SB3A and SB3C22 Veins Xylem Phloem Vein Cuticle Epidermis Palisade mesophyll Epidermis Stoma Guard cells Spongy mesophyll The Internal Structure of a Leaf

7/7/2016SB3A and SB3C23 Leaves All leaves have Stomata  Stomata allow for gas exchange Close at night and when losing too much water  Guard Cells control the opening and closing of the stomata guard cellsstoma

Leaf Adaptations Extreme temperature (pine needles) Water loss (cactus spines) Aquatic environments (water lilies) Getting food (Venus flytrap) 7/7/2016SB3A and SB3C24

Review Alternation of generations  Plants alternate between the two  Each cycle divides by mitosis 7/7/2016SB3A and SB3C25 fertilization meiosis SPOROPHYTE PHASE GAMETOPHYTE PHASE

Review Sporophyte phase is diploid  Begins with fertilized egg  Spores produced through meiosis Gametophyte phase is haploid  Begins with spore  Gametes produced through mitosis 7/7/2016SB3A and SB3C26

Flowers Purpose: Reproduction  Male Parts: Stamen Anther  Produces pollen Filament  Supports the anther  Female Parts: Pistil Stigma  Sticky top Style Ovary  Produces fruit 7/7/2016SB3A and SB3C27 stamen filamentanther carpel style stigma ovary

7/7/2016SB3A and SB3C28 Flowers Examples of Fruits:  Grapes  Apples  Pears  Peas  Corn  Wheat  Walnuts  Tomatoes  Pineapple  Pumpkins  Watermelons  Cherries  Cucumbers

7/7/2016SB3A and SB3C29 Filament Anther Stigma Style Ovary Carpel Petal Sepal Ovule Stamen The Structure of a Flower