Plants

I. Nutrition

A. Autotrophs (make their own food) by photosynthesis

B. Photosynthesis – use CO2 and water w/ energy from Sun to make glucose

C. Chlorophyll (green pigment in chloroplasts) traps light energy and turns it into STORED chemical energy in the bonds of glucose

I. Nutrition

D. 6 CO2 + 12 H2O = C6H12O6 (glucose) + 6 H2O + 6 O2

E. Glucose is then stored as starch and used when needed

F. Most photosynthesis on Earth is from algae in oceans

I. Nutrition

G. Most photo for land plants happens in leaves

1. Thin and flat (more surface area)2. Structure

a. Epidermis – protects leaf from water loss, injury, fungus

b. Cuticle – waxy coating on leaves to protect from water loss

c. Stomates – openings on underside of leaf, allows gas exchange w/ environment

I. Nutrition

d. Palisade layer – under epidermis, tall cells filled w/ chloroplasts, most photo occurs here

e. Spongy layer – loosely arranged cells for inc surface area, gas exchange

f. Veins – conductive tissues, carry water and minerals from roots through stem to leaves, carry food from leaves to rest of plant

II. TransportA. Roots

1. Absorb water and minerals from soil and move them to stem

2. Anchor plant to ground

3. Store extra food as starch (potato)

4. Have root hairs for inc surface area for inc absorption (carrots, grass)

II. TransportB. Stems

1. Xylem (water from ground to leaf) and Phloem (food from leaf to ground) connects roots to leaves

II. TransportC. Leaves

1. Have “veins” of xylem and phloem to move food and water

III. RespirationA. Gases exchanged through stems,

leaves and roots

B. Intercellular spaces open to env through stomates

C. Stomates open/close for more/less gas exchange

IV. Excretion

A. Waste from photo (water and O2) are used for cell respiration

B. Waste from cell resp (CO2) used for photosynthesis

C. Extra gases pass out through stomates

V. Regulation

A. Plant Hormones1. Produced by cells in growing regions of

plant (tips of roots, stems, buds)

2. Can cause plant to grow towards light or water

VI. Reproduction

A. Asexual Reproduction – vegetative propagation (bulb, cuttings, runners)

B. Sexual Reproduction (flowering plants)

1. Structuresa. Sepals – “lower” leaf, protect the flower bud

b. Petals – surround repro organs of flower (bright color and smell)

VI. Reproductionc. Stamens – male sex organs, have anther

(make sperm (pollen) by meiosis) and filament (support anther)

d. Pistil – female sex organs, stigma (sticky part to receive pollen), style (connect stigma to ovary) and ovary (contains egg cells (ovules))

VI. Reproduction

2. Some species have ♂ and ♀ organs, others only have ♂ plants and ♀ plants

3. Pollinationa. Self – pollination – pollen from one flower

goes to stigma of a flower on same plant

b. Cross pollination – pollen from different plants (inc genetic variation in offspring)

c. Carried out by wind, insects or birds

VI. Reproduction4. Fertilization

a. Pollen lands on stigma and germinates, forming pollen tube to send sperm to ovule

b. After fert, ovule forms seed and ovary forms the fruit

VI. Reproduction

5. Seeds a. Contain developing plant and food for plant

VI. Reproduction6. Fruits

a. Seed dispersal – carry seeds away from plantb. Wind – Maples and dandelions

c. Water - coconuts

d. Animals – cockleburs attach to fur of animals and are carried away