Plant Parts & Their Jobs

Plant JobsWrite these down…

Primary source of food for people and animalsProduce oxygen

Absorb carbon dioxide

Continued…

Plant JobsSlow wind speed Provide homes for wildlifePrevent erosionBeautify surroundingsFurnish building materials and

fuel

Parts of a plantFour basic parts

LEAVESSTEMSROOTSFLOWERS

Draw this on your notes

LEAVES

The greenest part of the plant

Act as solar collectors

Large leaves= areas of little sunlight

Tiny leaves = bright sunlight

Needles = no water loss

LEAVES

LEAVES - structure Epidermis - top and bottom tough layer

Pallisade Layer - most cells with chloroplasts are found here

Spongy Layer - gas exchange through stomata

LEAVES - 2 functions Make Food

(sugar) in the chloroplasts

Gas Exchange

take in carbon dioxide andrelease oxygen and watervapor

Stomata on the bottom of the leaves have guard cells that open and close as they fill up with water.

LEAVES - photosynthesis

Plants make sugar using CO2 (from air)

and H2O (from roots)as ingredients.

STEMS

STEMS - two main functions

Liquid transport

xylem cells carry water

& minerals up phloem cells carry

food down Support

STEMS – example Dicot plants such as a bean (xylem & phloem in a ring under the bark)

Xylem PhloemCambium

STEMS – example Monocot plants such as a corn stalk (vascular bundles scattered throughout the setm)

Xylem tube

Phloem Cells

What Good Are Stems to humans?

FOOD-rhubarb, celery, white potato

WOOD – building and fuel

PAPER

Types of Modified Stems Bulbs: (onion) Tubers: (potato) Stolons: above ground runner (strawberry) Rhizomes: below ground runners (field bindweed or creeping jenny)

ROOTS

ROOTS - functions Anchor plant Suck up water and

minerals Store Sugar (radish,

carrot, beets) Reproduction (eyes on potatoes)

ROOTS - structure root cap-protects tender cell division

area as the root pushes through soil

ROOTS – root hairs

Water and minerals move into root by osmosis / diffusion

What is Diffusion? Diffusion is when

particles move from areas of high concentration to low concentration. (Doesn’t have to be water)

Examples: Lighting a match, spraying perfume or cologne

What is Osmosis? Osmosis is a special

type of diffusion that involves water.

Water moves from areas of high concentration to areas of low concentration.

Diffusion is when particles move from areas of high concentration to low concentration.

FLOWERS, FRUITS, SEEDS

FLOWERS, FRUITS, SEEDS Main jobs involve

reproduction

Attract pollinators Disperse pollen Fertilization Disperse seeds

FLOWERS, FRUITS, SEEDS POLLEN normally carried by

insects or wind

FRUITS & SEEDS normally carried by wind, animals, water or shot away from parent plants (projectiles)