Science - Ch 10


Asexual Reproduction


*does not require sex cells*offspring is genetically identical to parent*can be grown from roots, stems, leaves


Sexual Reproduction


*requires making of sex cells-sperm (male sex cell)-egg (female sex cell)*offspring is genetically different to parent*fertilization occurs-combining of sperm and egg to form zygote--first cell of new organism*happens through dispersal-carrying sperm to egg-by wind, water, animals, gravity


2 Stages to a Plant's Life Cycle


1) Gametophyte2) Sporophyte


Gametophyte Stage


*produces sex cells*produces haploid cells-half the set of chromosomes for an organism*allows fertilization to occur*producing a zygote*non-vascular plants spend most of life


Sporophyte Stage


*forms spores*produces diploid cells-have full set of chromosomes (pair up)*spores go through cell division*vascular plants spend most of life


Moss Life Cycle


> sporophyte >> spore >> gametophyte >< zygote << fertilization << sex cells <
*sporophyte cannot do photosynthesis*gets nutrients and water from gametophyte


Alternation of Generations


*switching from sporophyes producing gametophytes, etc.


Fern Life Cycle


> frond (sporophyte stage) >< prothallus (gametophyte stage) <


Gymnosperm Reproduction


*cones - contain the reproductive cells

Male Cone*smaller in size*grows on tip of branches*has pollen-contains sperm
Female Cone*larger in size*grows along the branch*produces egg from ovule


Gymnosperm Reproductive Process


1) Pollination2) Forms a Pollen Tube3) Fertilization4) Zygote5) Embryo


Pollination


*transfer of pollen to the ovule*by dispersal-movement of pollen or seeds by wind, water, insects, animals, gravity


Forms a Pollen Tube


*allows sperm to get to egg


Embryo


*yound plant that will form a seed


Angiosperm Reproduction


*reproductive organ>flower


4 Parts to a Complete Flower


1) Petal2) Pistil3) Stamen4) Sepal


Receptacle


*part of stemF*allows flower to grow


Sepal


*leafy part of flowerF*protects flower (bud)F*supports stem


Petal


*colored part of flowerF*attracts for pollination


Stamen


*contains male reproductive cell


2 Parts to a Stamen


A) AntherB) Filament


Anther


*sticky substance that contains pollen*contains sperm - male sex cell


Filament


*"stem" of stamen


Pistil


*contains female reproductive cell


3 Parts to a Pistil


A) StigmaB) StyleC) Ovary


Stigma


*top sticky partF*collects pollen


Style


*"stem" of pistilF*forms a pollen tube


Ovary


*contains ovule-contains eggs


Angiosperm Reproductive Process


1) Pollination2) Forms a Pollen Tube3) Fertilization4) Zygote5) Embryo


Seed


*mature ovule


Fruit


*mature ovary


Germination


*new seed developing into a new plant