Plant Sex Pollen Grain – male gamete – many forms of distribution – wind, animal, water Ovule – Female gamete – inside flower

Pollination – transfer of pollen from anther to pistil Pollen makes a pollen tube to egg then fertilizes the egg, makes seeds

Ovules

Ovules

Pinecones – reproductive organs Modified leaves formed in circles Male cones contain pollen Female cones open for pollination then close until seeds mature then reopen for dispersal – can take up to 2 years

Asexual Reproduction in plants Vegetative – modified stems (runners, bulbs, tubers, rhizomes)

Plant Parts Vascular tissues – vessels that carry nutrients & water through the plant - xylem – carries water and minerals up from roots - phloem – carries sugars down & around Roots – take up water & nutrients from soil, anchor plant

Stem – houses vascular tissues & supports leaves – 2 types 1. woody – non-green 2. herbaceous – green, flexible

Leaves- major photosynthetic organ of plant - blade – flat part - petiole – stem If blade is divided, called leaflets

Germination Embryo resumes growth, root emerge 1 st, shoot 2 nd Some plant first send a hook up to protect plant others send up cotyledons

Plant Life Span Perennial – all woody, some herbaceous - live several years - most reproduce several times – some only once Annual – grows, flowers, reproduces & dies in 1 growing season – almost all herbaceous - corn, beans, sunflowers

Biennial – live 2 seasons – carrots, onions – 1 st year stores nutrients – 2 nd year produces flower, makes seeds and dies

Plant Behaviors Tropisms – response when a plant grows toward or away from a stimulus - toward=positive tropism - away=negative tropism

Dormancy – some plants or seeds remain inactive until they have been exposed to low temps for several weeks