Plant Structures, Reproduction, and Responses

Levels of Organization

Copy this graphic organizer into your journal

What are the 2 Types of Plants? BRYOPHYTES Mosses, liverworts, hornworts NO tissue to transport water and nutrients NON Vascular TRACHEOPHYTES Vascular plants Have tissue for transporting water and nutrients

What is Vascular Tissue? Function: to transport water and nutrients between roots, stems, and leaves 2 Types: Xylem: transports water from roots to shoots Phloem: transports sugar from leaves to roots (and the rest of the plant) Like our circulatory system Stem Cross-Section

What are the organs of the plant? Roots Stems Leaves

What kinds of roots are there? STRUCTURE: Taproot – long, thick root that is the main root of the plant Fibrous roots – many, smaller branching roots

What are the functions of Roots? Anchor the plant to the ground Absorb water and minerals Store sugars or starches

What are the functions of the Stem? Growth of the plant, including production of leaves, branches, and flowers Support – stems hold leaves up to the light Transport of water and sugars between the roots and leaves

What are the functions of the leaf? Photosynthesis – plant cells use sunlight to convert carbon dioxide and water into sugars 6 CO2 + 6 H2O + light  C6H12O6 + 6 O2 Transpiration – water is pulled from the roots and stems of the plant as it evaporates from the surface of the leaves Gas exchange – leaves take in carbon dioxide for photosynthesis and release oxygen and water vapor into the air

What are the Parts of a Leaf? blade: the flat part of the leaf that catches sun Petiole: the thin stalk that attaches the leaf to the stem

Important Leaf structures Stomata / Stoma Pores on the undersides of leaves Control transpiration rate and allow gas exchange Guard cells are specialized cells that control the opening and closing of the stomata No line

Draw and label this in your journal.

What are some examples of Modified Leaves? Tendrils for climbing Spines to reduce transpiration rate Succulent Leaves for water storage Bracts to attract pollinators

What is Transpiration? Loss of water from a plant through its leaves. The force that pulls water from the roots up to the leaves.

What is a Conifer (Gymnosperm)? Plants that produce seeds in cones No fruit = “Naked seed”

What are Angiosperms? Flowering plants Produce seeds inside fruit                                                                                                            

What are the 2 types of Flowering Plants? Monocots Contain ONE seed leaf Dicots Contain TWO seed leaves

What is a Cotyledon? The seed leaf (inside the seed) One cotyledon (seed leaf) Two cotyledons (seed leaves)

What are flowers? Modified leaves that are for sexual reproduction

draw and label flower in your journal

What is the Pistil ? Female Reproductive Structure stigma receives the pollen from the anther pollen grows a tube down through the style ovary produces females gamete and protects developing seed Draw this in your journal

What is the Stamen? Male Reproductive Structure anther produces pollen pollen - male gamete, powder filament is a stalk that supports the anther Draw this in your journal

What is Pollination? The transfer of pollen from a stamen to a pistil

What are some Methods of Pollination? Wind Water Gravity Insects/animals

The union of the pollen and ovule What is Fertilization? Pollen lands on stigma Travels down style Joins with ovule Ovary becomes fruit Seeds develop inside fruit The union of the pollen and ovule

What are the steps of fertilization? Draw this in your journal Pollen lands on stigma Travels down style Joins with ovule Ovary becomes fruit Seeds develop inside fruit

What is Germination? When the baby plant sprouts from the seed and begins to grow

What are Tropisms? A plants’ growth in a certain direction in response to a stimuli

What are the types of tropisms? Phototropism - growth towards light Geotropism – response to gravity Roots toward gravity (+) Stems and leaves away from gravity (-) Hydrotropism – growth towards water Thigmotropism – response to TOUCH!

What are some Plant Hormones? Auxins – controls growth and cell elongation, inhibits lateral (side) growth, stimulates root growth Cytokinins – stimulates cell division, opposite of auxins Gibberellins – stimulates growth and stimulates seed germination Abscisic Acid – slows or stops cell division (growth), promotes seed dormancy Ethylene – stimulates fruits to ripen, causes leaves to fall in autumn