Objective 14.01

What are the major parts of a plant including the anatomical parts

and what are the distinguishing characteristics of each?

Plant Parts

• Leaves

• Stems

• Roots

• Flowers

Leaves-External

• Petiole-leaf stalk or part that connects the leaf to the stem

• Blade-the large, flat part of the leaf

• Midrib-the large center vein

• Veins-the structural framework of the leaf

• Margin-the edge of the leaf

Leaves-External

Leaves-Internal

• Upper and lower epidermis-skin of the leaf that prevents the loss of too much moisture

• Stomates-small openings under the leaf for breathing or transpiration

• Guard Cells-open and close stomates

Leaves-Internal

• Chloroplasts-small green particles that contain chlorophyll– gives leaves their green color– necessary for photosynthesis

Leaves-Internal

Leaves-Internal

Stems-External

• Lenticels-breathing pores• Bud scale scars-show where terminal

buds have been located• Leaf Scars-show where leaves were

attached• Terminal bud-bud on the end of a stem• Axillary or lateral bud-bud on side of

stem

Stems-Internal

• Xylem-tissue that transports water and nutrients up from the roots to stems and leaves

• Phloem-tissue that transports food down from leaves to roots

Stems-Internal

PhloemPhloem

Xylem

Stems-Internal

• Cambium-thin, green, actively growing tissue located between bark and wood and produces all new stem cells

• Bark-old inactive phloem

• Heartwood-old inactive xylem

• Sapwood-new active xylem

Stems-Internal

Cambium

Heartwood

Sapwood

Bark

Stems-Internal

• Monocota-plant stems have vascular bundles that contain both xylem and phloem in each bundle– examples: corn, grasses

• Dicata-plant stems have the phloem layer and xylem layer separated by cambium– example: trees

Stems-Internal

Monocot Dicot

Roots-External

• Root cap-indicates growth of new cells

• Root hairs-absorb moisture (water) and minerals

Root images from a rice plant

Roots-Internal

• Much like stems in that they have a phloem, cambium, and xylem layer

• Phloem-the outer layer that carries food down the root

• Xylem-the inner layer that carries water and minerals up to the stem

Layers of Roots

• Fibrous-many branched shallow roots– are easier to transplant

• Tap-long root with few branched ones– more difficult to transplant

Flowers

• Sepals-Green parts that cover and protect flower bud before it opens

• Petals-are really leaves that are modified to attract insects for flower pollination, the pretty part that we call flowers

• Stamen-male part of the flower

• Pistil-female part of the flower

Flowers

Parts of the Stamen

• Filament-short stalk that holds up the anther

• Anther-a sac-like structure that contains pollen, the male sex cells

Parts of the Pistil

• Ovules-the eggs or female sex cells that become seeds if fertilized

• Ovary-if fertilized becomes a fruit or seed coat

• Style-holds up the stigma and connects it to the ovary

• Stigma-sticky part on top of style where insects leave pollen

Parts of the Pistil

Stigma

Style

Ovary

Complete-vs-Incomplete

• Complete flowers have both male and female parts

• Incomplete flowers have only male or female parts

• What are the major parts of a plant including the anatomical parts and what are the distinguishing characteristics of each?