PLANTS ARE PRODUCERS PLANTS CAPTURE ENERGY FROM THE SUN. –The sun’s heat & light provide the energy almost all organisms need to live. –Light energy must be changed into chemical energy (the form of energy all organisms use to carry out the functions of life). Plants capture energy from the Sun & convert it to chemical energy (via photosynthesis). PLANTS ARE ADAPTED TO DIFFERENT ENVIRONMENTS PLANTS RESPOND TO THEIR ENVIRONMENT PLANTS RESPOND TO SEASONAL CHANGES

PLANTS & SUN PHOTOSYNTHESIS: plants use sunlight to make chemical energy(in energy rich sugar molecule) Sunlight + 6CO 2 +6H 2 O  C 6 H 12 O 6 + 6O 2 Most photosynthesis occurs in leaf, stem holds it up to sun, and roots anchor in soil and give H 2 0. AUTOTROPH= self- feeder; another name for plants Algae, some bacteria & some protists also use photosynthesis Plants are mulitcellular though & can store more energy than the others Starch = energy rich molecule made of sugars plants store energy in. Cellular respiration = how cells break down sugars for energy release. (C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy) Some plants store starch in roots (carrots/beets) & others in stems (rhubarb)

PLANTS ADAPT TO DIFFERENT ENVIRONMENT Almost all land has some type of plants GRASSES: deep roots, quickly makes seeds, found in most environments (as longs as roots survive, grass grows back) TREES: not survive if leaves/stem die; need lots water; coniferous (needle-leaves stay green) do well in cold, deciduous(lose leaves in cold)need long growing season Some plants (desert & snowy mountain) must reproduce quickly while timing is good for them (seeds sprout, flowers grow, & new seeds made within just a few weeks)

PLANTS ADAPT TO ENVIRONMENTS Some plants adapt to protect: mustard gives off odor; poison ivy & oak make chemical & tobacco makes nicotine (poison) to keep insects from eating them. Venus fly trap has teeth on leaf edges to capture insects & makes digestive fluid to break insect down for important materials not found in local soil

Plants Respond to Environment Plants respond to stimuli (change in environment causing a response) to survive & grow. Gravity: roots drawn down & stems grow up, even if seedling is on its side. Touch: “tendrils” (found in peas, & climbing plants) are special stems that wrap around objects to grow upward to sun Light: stems grow towards it; plant releases auxin (plant hormone) at tip of stem. This moves away from light & stimulates cell growth, causing plant to bend towards the sun.

PLANTS RESPOND TO SEASONAL CHANGES Shorter time of daylight affects amount of sunlight available for photosynthesis. So plant goes into “dormancy”. Plant stops growing & needs less energy.

PLANTS RESPOND TO SEASONAL CHANGES In temperate climates, approach of winter causes leaves of deciduos trees to die & drop to ground. In some plants (like trees) they go into dormancy & grow in spring again; in others (like wild cornflowers) they die and only grow back in spring due to seeds left behind. Short-day plants (rice/ragweed) only flower in fall or winter; long-day plants (lettuce/spinach) flower only in late spring & summer.