7th Grade Science

PLANTSYSTEM

S

LEARNING OBJECTIVESUnderstand the basic structure

and function (job) of the tissues, organs, and organ systems of plants

Consider the similarities between animal systems and plant systems

Plant CELLS (review)Have all the same basic parts as

animals EXCEPT also have a CELL WALL and CHLOROPLASTS

Larger vacuoles for storing water

Usually have a more square shape

Plant TISSUESTissues = cells that are working

in a team to do the same job (function)

Xylem & Phloem TissueAre the

“circulatory system” of the plant

Both are TUBES used for transport

Xylem & Phloem TissueXylem

(pronounced zi-lem) tissue is made of tubes that carry WATER and MINERALS

(*usually upward from the roots to the rest of the plant)

Usually xylem tubes are larger (in

diameter)

Xylem & Phloem Tissue

Phloem (pronounced flo-em) tissue is made of tubes that carry FOOD (or SUGARS)

(*usually downward from the leaves to the rest of the plant)

Phloem Tube

Xylem & Phloem TissueForm the “veins” in leaves

Also called “vascular” tissue

Each line = a vein

(made of xylem & phloem tissue)

Xylem & Phloem TissueXylem

Tissue

Phloem Tissue

Xylem & Phloem Tissue

Plant ORGANSOrgans = 2 or more tissues

working together to do the same job (function)

ROOTSJobs of a Root:

Absorb water & minerals from the soil.Transport water & minerals up to stem

& leaves.Anchor the plant in soil.Store food (ex. carrot, radish, & turnip)

STEMSJobs of a Stem:

To support leaves and flowers

To transport water, minerals, and food

To store and sometimes make food

STEMS

LEAVESJobs of Leaves

Take in sunlight to make food (photosynthesis)

Chloroplasts are the organelle that make this possible in plant cells

LEAVESChlorophyll is the molecule

in green parts of plants that uses the energy in sunlight to turn water (H2O) and carbon dioxide gas (CO2) into sugar (glucose—C6H12O6) and oxygen gas (O2). This process is called photosynthesis.

LEAVES Leaves come in many

sizes and shapes; they are often used to help identify plants.

Plant spines (like cactus spines) are actually modified leaves

LEAVES

A leaf is made of many layers that are sandwiched between two layers of tough skin cells (called the epidermis). Label as #1

The epidermis also secretes a waxy substance called the cuticle (2). These layers protect the leaf from insects, bacteria, and other pests.

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2

Label your diagram as we go! (Add the numbers and

arrows!)

LEAVES Among the epidermal

cells are pairs of sausage-shaped guard cells (3). Each pair of guard cells forms a pore (called stoma; the plural is stomata-4).

Gases enter and exit the leaf through the stomata.

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4

LEAVESMost food production

takes place in mesophyll cells. Gas exchange occurs in the air spaces between the oddly shaped cells of the spongy mesophyll (5).

5

LEAVESVeins (6) support the

leaf and are filled with vessels that transport food, water, and minerals to the plant through branches. 6

LEAVES video clips Photosynthesis by Brainpop

Autumn Leaves by Brainpop

Leaves Video Clip-Discovery Channel

FLOWERSJobs of Flowers

reproductive system of seed plants

FLOWERSParts of the flower include:

opetals

PETALS

FLOWERSParts of the flower include:

sepals

SEPALS

FLOWERSParts of the flower

include:

opistil (the female reproductive organs)

FLOWERSParts of the flower include:

ostamens (the male reproductive organs).

FLOWERSCan you

identify the male and female parts of this flower?

SEEDSFlowers

produce fruits, which grow seeds that can mature into new plants

SEEDSGERMINATION =

when a seed starts growing

SEEDS

Can you see the new baby plant at the

bottom of the peanut?

FLOWERSFRUITS come from FLOWERS!

*Anything that has SEEDS on the inside is

a FRUIT!!!

FLOWERS video clips Pollination by Brainpop

Plant Growth by Brainpop Flower Parts by Discovery Channel

Miscellaneous video clips

Extreme Plant Adaptations—Discovery Channel

Sources