All about Plants!

The importance of plants….. Primary source of food Major producers of oxygen Keep us cool Renew the air Slow down the wind Hold soil in place Provide a home for wildlife Beautify our surroundings Perfume the air Furnish building materials and fuel

Objective A Students will be able to identify parts of the plants and discuss their functions;

Major Plant Parts Vegetative Parts: Reproductive Parts: Roots Stems Leaves Reproductive Parts: Flowers

Roots Functions Absorb water and nutrients Anchor plant and support the aboveground part of plant Store food to be used later Need to grow constantly for plant to stay healthy First structure to form from seed Plant health is closely tied to root health

Root Structure Primary Root- first root to grow from the seed. Secondary Roots – grow from primary root Both have Root Hairs – they help anchor the plant, absorb water & nutrients

Root Structure Apical Meristem Root Cap: Covers and protects apical meristem as it pushes through soil particles Epidermis: Where water and minerals enter root Root Hairs: Projections that increase root surface area allowing greater moisture and nutrient uptake

Root Systems Fibrous Root :A system that has no dominant primary root Taproot: A system composed of one primary root and many secondary roots that branch off

Root Nodules Swellings (bumps) on the roots Rhizobium bacteria live in these bumps they take nitrogen from the air and combine it with oxygen to make it useable to the plant puts nitrogen in the soil so that crops that grow there later may use the nitrogen

Legumes Legumes are the group of plants that can do this Soybeans, clover, alfalfa, beans, peas

Root Health Healthy Roots: Roots are white or nearly white, and smell fresh. Unhealthy Roots: Roots are black, brown, or dark orange and smell rotten and sour.

Root Health Watering properly drastically affects the plant’s health Drainage holes in the pot Soaked with water until it drains out the bottom encourages plant growth throughout the entire pot Allow soil to dry slightly between waterings

Stems All stems look very similar, but upon closer observation there are many differences!

Functions of Stems Support leaves, and position them so they can receive as much sunlight as possible Responsible for size and shape of plant Move water, minerals, and manufactured food throughout whole plant Green stems produce food through photosynthesis

Stems External Structures: Terminal Bud: Bud located at end of stem Apical Meristem: Contained inside terminal bud; responsible for stem growth. Node: Place where leaves are attached to stem Internode: Area between nodes

Stems External Structures: Lateral Buds: Buds located on side branches Bud Scales: Protective structures located on outside of terminal and lateral buds Lenticels: Small spots on stem that allow a stem to exchange gases with its environment

Stems Internal Structures: 3 Types of Tissues used for transport of materials Xylem, Phloem, and Cambium Arranged by Small bundles scattered throughout stem OR Rings or a ring of bundles

Stems Internal Structures: Xylem: Tissue responsible for carrying water and nutrients from roots to leaves; located near center of stem Xylem Up!! Phloem: Tissue responsible for carrying food produced in leaf to rest of plant; usually located near outside of stem Phloem Down!!

Stems Internal Structures: Cambium: Tissue responsible for the production of new xylem and phloem. It is found between the xylem and phloem.

Specialized Stems Bulbs: Short flattened stem which has several fleshy leaves. Bulbs are found beneath the soil. Example: Onions Corm: Spherical structure similar to a bulb Example: Gladiolus

Specialized Stems Rhizome: Thick underground stem which lies horizontally. Example: Mother in Law’s Tongue Stolon: Horizontal stem which lies above the ground (often called runners). Example: Strawberry runners

Specialized Stems Tuber: Rhizome with a tip swollen with stored food Example: Potatoes

Leaves Produce food for the plants Functions Produce food for the plants Efficiently collect light and use that light to make energy

Activity #2 Instructions Supplies Needed: 1 leaf 1 piece of paper 1 crayon Instructions Using the crayon and rub the image of the leaf in the middle of the page.

Label Your Picture

Leaf Parts Leaf Blade: Large, broad, flat surface whose job is to collect sunlight Petiole: supports the leaf and holds it away from the stem. Midrib: Main vein running down the center of the leaf. It helps hold the leaf so it is facing the sun.

Vein Patterns Parallel: Veins never cross; found in monocots Netted: Veins form a network; found in dicots

Leaf Types Simple Leaf: Has only one leaf on the petiole. Compound Leaf: A leaf with multiple blades.

Leaf Layers Cuticle: Top waxy, non-cellular part of leaf; prevents water escaping Epidermis: Skin like layer of cells found on top and bottom; protects leaf

Leaf Layers Palisade Mesophyll: Layer of cells standing on end directly below upper epidermis; responsible for photosynthesis Spongy Mesophyll: Loosely packed cells located beneath palisade mesophyll; responsible for holding products of photosynthesis

Leaf Layers Stomata: Holes in lower epidermis responsible for gas exchange. Guard Cells: Surround stomata's which open and close them.