Botany- gymnosperms and angiosperms

conifers, ginkgo, cycads, gnetophytes

4 phylums of gymnosperms

female gametophyte

produced inside an ovule that contains a megasporgium (nucleus) and is enclosed by integument

sporophytes

mostly trees and shrubs of the gymnosperns

gametophytes

gymnosperms- tiny and develop within sporophytes

gymnosperns

seeds are a result of a single fertilization

gymnosperms

fertilization does not require water

seed advantage

dormant state of seeds enable seed plant to survive during periods of cold winter and drought

seed coat serves as a barrier against bacterial fungal decay

seeds attract seed-eating animals for seed dispersal

seeds include food for the embryo and germinating seedling

pines

largest genus of conifers

bristlecone pines

world’s oldest known living organisms -pines

needlelike

pine leaves are ____ and arranged in clusters of bundles of two to five leaves

fascicle

the cluster of pine leaves are called ___ and forms a cylindrical rod if the leaves are held together

hypodermis

_____ located below the epidermis

resin canals

____ develop into mesophyll

tracheids

most gymnosperm wood consists primarily of ____ and no vessel elements or fibers

-example is softwood

conifers

mycorrhizal fungi associated with the roods of most ____

heterospory

pines are ___, producing two types of spores

pollen cones

pines have ____ (male strobili) consist of papery scales arranged in a spiral around an axis

mircosporangia

pollen cones have ___ which develop in pairs toward the base of the scales

mircospore

pollen cone- each ___ devlops into a winged pollen grain (immature gametophyte), consisting of two prothallial cells, a generative cell, and a tube cell

generative cell

pollen grain produces a pollen tube

_____ enters the pollen tube and divides into sterile cell and spermatogenous cell - two sperm (no flagella)

gametophyte

the germinated pollen grain, with its pollen tube and two sperm, constitutes the mature male ______ (no antheridium formed)

seed cones

ovulate cones/female strobili- consist of woody scales with bracts (at maturity) arranged in a spiral around an axis

megasporangium; micropyle

seed scale bears two ovules on its upper surface. each ovule consists of a multicellular nucellus (_______) surrounded bu the integument with an opening called _____

megasporocyte; meiosis

the _____ within the megasporangium undergoes ____, producing four megaspores

gametophyte

out of the four megaspores produced in meisosis, only one megaspore develops into female ____

two or three archegonia differentiate at the mircopylar end

pollination

about 15 months after ___, the tip of the pollen tube arrives at the archegonium

gametophyte

pine-reproduction

one sperm unites with the egg to form a zygote then embryo nourished by the female ____

ginkgo

only one living species of this gymnosperm phylum

ginkgo

this gymnopserm has notched, broad, fan-shaped leaves

leaves are produced in a spiral on short, slow-growing spurs

no midrib or priminent veins

hair-like veins branch dichotomously

ginkgo

no midrib is a characteristic of

the cycads

appearance of a cross between a tree fern and a palm

slow-growing plants of the tropics that have tall unbranched trunks

crown of largely pinnately divided leaves

cycads are dioecious= unisexual

the gnetophytes

unique among the gymnosperns in having vessels in the xylem

ephedra, gnetum, welwitschia

the genus of gnetophytes (3)

ephedra

more than half of the 70 known species are joint firs in the genus ___ of gnetophytes

gnetum

the remaining species of gnetophytes are in genus

these occur in topics

most are vine-like with broad leaves similar to those in flowering plants

welwithschia

the third genus of gnetophytes is the ___ and only has one species

confined in temperate deserts of southwestern Africa

average rainfall only 2.5 cm/year

only produce two leaves throughout their life span

endosperm

serves as food for the embryo and germinating seedling

developed from the primary endosperm nucleus

nutritive tissue

zamia pumila

the only species of cycad native to the US

welwitschia

this genus of the gnetophyta has only one species

angiosperms

plants with seeds contained within a vessel (carpel)

largest and most diverse phylum of the plant kingdom

anthophyta

the one phylum of angiosperms

angiosperms

unique features of this seed plant is - flowers, enclosed carpels, double fertilization

angiosperms

are heterosporous

the female gametophytes are wholly enclosed within sporophyte tissue and reduced to only a few cells

male gametophytes consist of a germinated pollen grain with three nuclei

both antheridia and archegonia are lacking

angiosperm

this is the development of female gametophyte of _____

diploid megasporocyte cell differentiates from all other cells in the ovule

undergoes meiosis and produces four haploid megaspores

integuments differentiate and eventually become the seed coat

functional megaspore, nucleus, mitosis

in angiosperms once the megaspores have been developed which one begins to enlarge and the _____ divides through ____

3, 8

how many times does the megaspore divide in angiosperms and how many total nuclei after this

and there are ___ nuclei in one group at the _____ end, the other 4 in the second group at the opposite end

egg apparatus

3 remaining nuclei at the micropylar end

consisting of an egg cell and 2 synergids

antipodals

the other 3 remaining nuclei at the other end of the ovule are called

megagametophyte

the eight-nucleate, seven-celled structure is the mature____, or embryo sac

male gametophyte

the formation of the _____ occurs in the anthers

the anther

consists of four groups of sporogenous cells, surrounded by several layers of sterile cells

the sterile cells- wall of pollen sac

mitosis

angisperms- mircosperms dividies by ____ forming

a large tube cell

a small generative cell

then the generative nucleus divides into 2 sperm

mircogametophyte

angiosperm- two sperm cells+tube cell=mature

pollination

angiosperm- ___ is the transfer of pollen grains from the anther to a stigma

double

do angiosperms have single or double fertilization

primary endosperm nucleus

angiosperm- the other sperm unites with the central cell nuclei (triple fusion, 2n+n) forming the

angiosperms

flower and fruit are defining characteristics of the

female

angiosperms- ____ gametophytes are wholly enclosed within sporophyte tissue and reduced to only a few cells

male

angiosperms- ___ gametophyte consist of a germinated pollen grain with three nuclei

wall of pollen sac

the anther- the sterile sells that around it is called