Plants

Are Plants Heterotrophic or Autotrophic?

Plants are autotrophs

Autotrophs- they create their own food

Aboveground parts of the plant and their Function:

Aboveground: Shoots

Leaves stems: produce food by photosynthesis

Flowers: reproduction

Aboveground: steam and leaf

Major stem

Secondary stems branch off

Terminal bud: shoot tip

Auxiliary bud: location of secondary stem growth

Petiole: stalk attaching leaf to stem

Node :location on stem of left attachment

Belowground portions of the plant and their functions

Belowground: roots

Absorb water and minerals

Store food

Apical meristem

located on the top of the plant and on the bottom of the root. It is where cell division is taking place and the plant is growing vertically.

Contain unspecialized cells

Lengthen shoots and roots

Located at the tip of the shoot and the bottom of the root

Lateral Meristem

located around the plant. It is where cell division is taking place and the plant is growing hora

Increases girth of older roots and stem

Cylindrical arrays of cells zontally.

Eudicots and Monocots

Eudicots

Have two cotyledons

Vascular tissue is arranged n a ring

Monocots

Have one cotyledons

Vascular tissue arranged in random

Vascular Tissue

Vascular tissue: transport water and nutrients

Xylem transports water

Conducts water

2 cells: vessel member and tracheid's

dead at maturity

Interconnected for vertical and lateral water movement

Phloem Transport nutrition (food)

Conducts sugar

One cell: sieve member

Alive at maturity

Connect end to end

Helper cell: companion cells

Loads of surgar

Leaf Tissues

Mesophy II

Photosynthetic tissue between the epidermis

2 rows, columnar shaped

Contain 80% of chloroplasts

Spongy: attached to lower epidermis

Epiderams

Single layer of cells

Upper and lower epidermis secrete waves into the outer surface forming the caticle

Helps conserve water and protects

Stomata and Guard cells

Guard cells

Regulate the gas exchange and water loss

Control stomata opening and closing

Contain chloroplast

Expand and contract with water gain and loss

Stomata

Pores in the lower epidermis

Allow water and gas diffusion

Help cool the leaf

Are simply the holes in the leaf where gas exchange and water loss take place

Root Structure

Primary root: main root

Tip is the apical meristem

Contains the root cap

Protects the root with slime

Sense gravity

Secondary roots (lateral): branch off from main root

Root hair: small extensions

Flower Structure

Receptacle: swelling at tip off peduncle

Attachment for other flower parts

Petals: inside of sepals

Brightly colored to attract pollinators

Collectively called the corolla

Sepals: outermost flower part

A small and green

Protects

Collectively called the calyx

Male Structure of the flower

Stamen

Located next to the petals

2 parts

Anther: sac at top

Produces pollen

Male gamete

Filament

Semi-rigid stalk

Female Structures of the Flowers

Carpel: sprats

Style: slender stalk

Stigma: enlargement at top

Gathers pollen during fertilization

Ovary: swollen bases

Holds ovules

Female gamete

Become seeds when fertilized

Ovary becomes fruit

Pollination and fertilization

Pollination: pollen grains released from an anther land on a stigma

Pollination is the delivery of pollen to the female structure of the plant

Fertilization: fusion of egg and sperm

actual coming together of the sperm and the egg.

Adaptation of life of land

Resistance to desiccation (drying Out)

Caticle: waxy coating to keep water in

Stomata: allow gases to pass in and out

Division of labor: leaves, stems, roots

Symbiotic relationship with fungi aid in nutrient acquisition

Vascularization: transport water to tissues

Changes in life cycle

Pollen, seeds, flowers: eliminate need for water to transport sperm

Angiosperms and Gymnosperms

Gymnosperm have “naked seeds

Seeds don’t form inside an ovary

4groups

Conifers

Cycade

Ginlrgas

gnetophytes

Angiosperms Flowering plant

Ovules and(after fertilization) seeds are enclosed in an ovary

3 major groups:

Magnolids: 9,200 species, suchas pepper plants

Eudicats: 170,000 species, including daisies

Monocats- 20 species, including grass

Seed Dispersal

Fruit structure is adapted seeds

Wind currents

Water current

Wax coats or air sacs to float

Animals

Have hooks or are sticky

Attach to fur and feathers

Eat fruits and excrete seeds

Explosions: self dispersal

Leaching and Erosin

Leaching: removal of nutrients in soil by water percolating through it

Erosin: washing away of soil by wind flowing water and ice

Purpose of Roots

Anchor the aboveground plat parts

Absorb nutrients and water

Storage and reduce endrosin

Root structures

Root cap: protects as it lengthens

Region of cell division: apical meristem

Region of Elongation: cells lengthen and widen

Region of maturation:maturecells differentiate into different types

Cohesion-tension theory of water

Water moves from high to low concentration due to osmosis

Transportation occurs at all plant surface exposed to air

Parts of xylem cells in tension

Extends from leaves to steam to roots

Phototropism

When plant adjust the rate and direction of growth in response to light

Results in more efficient photosynthesis

Photoperiodiism

A biological response to change in length of daylight relative to darkness

Thigmotroposm

A shift in growth due to an object

Guided by auxin and ethylene