To be successful today… Parent reflection due WED 11/15 Add to TOC and set up Notes: Plant Structures HW: Job for Life WS BYOD Color of the day is Phones are in put away in backpacks

Plant Structures Essential Question: How do the major structures contribute to the plant’s survival and overall life functions?

Recall…the levels of biological organization

Characteristics of Plants Eukaryotic Multicellular Autotrophs Cell walls made of cellulose

Importance of plants Earth’s major producers Provide food and shelter for many organisms Supply oxygen needed for respiration Take in CO2 and release O2

Major structures of land-living plants

1) Leaves Broad, flat organ that traps light energy Cells contain 1000s of chloroplasts (photosynthesis) Location for most photosynthesis in plants

Cross section of the leaf

Cuticle Protective waxy layer on leaves Prevents evaporation & tissues from drying out

Stomata Small pores in the cuticle of the leaf Regulated by guard cells - allow for gas exchange during photosynthesis Can close to prevent water loss – transpiration Stomata & guard cells

Types of Leaves The leaf of the pitcher plant is modified to attract & then digest insects & other small prey due to lack of nitrogen. Cactus leaves are actually nonphotosynthetic Thorns that protect against herbivores.

The narrow leaves of a pine tree contain a waxy epidermis as well as stomata shrunken below the surface of leaf to reduce water loss. The leaves of a rock plant are adapted for hot, dry conditions. They are round, with few stomata, and often have clear tissue that allows light to penetrate into the leaf.

2) Roots Plant organ that: Anchors plant in ground Absorbs water & minerals from soil (assisted by root hairs) Transports nutrients to stem

3) Stem Provides support for upright growth Some green stems may also carry out photosynthesis Contains vascular tissues for transporting nutrients from one part of the plant to another

Two types of vascular tissues: xylem & phloem

Sugar/food moves from leaves to roots Phloem: Sugar/food moves from leaves to roots Xylem: Water moves from roots to leaves

Types of Stems A tuber is a stem, usually growing underground, that stores food. Ex. potato A rhizome is a horizontal, underground stem. New shoots can form allowing the plant to undergo periods of dormancy. Ex. ginger

central stem surrounded by short, thick leaves. that protect the bulb A bulb is made up of a central stem surrounded by short, thick leaves. that protect the bulb & store food. Ex. Onion, garlic

4. Flowers ~ structures that aid in reproduction