related to plants
Group Charophytes(green algae)
-homologous chloroplast:charophytes match plants in
having chlorophyll b & beta-carotene as accessory
pigments,chloroplasts similiar to plant chloroplasts
(have thylakoid membranes stacked as grana)
-biochemical similarity:cellulose(structural
component) in cell walls (same as plants)
-only algae w/ peroxisomes (same as enzyme composition
of plant)
-Similarity in mechanisms of mitosis & cytokinesis-
During cell division, nuclear envelope completely
disperses during late prophase, & mitotic spindle
persists until cytokinesis begins(in some charophytes,
cytokinesis involve cooperation of microtubules,actin
microfilaments, & vesicles in formation of cell plate)
like plants
-Similarity in sperm ultrastructure-More similiar to
plants than green algae
-Alternation of generation didn't occur
-Found in shallow water around edges of ponds & lakes
(modern charophytes)
-Inhabit shallow-water habitats subject to occasional
drying(ancient charophytes)
-Adaptation to living in shallow water-protection of
developing gametes & embryos w/in jacketed organs
(gametangia) on the parent
Group Bryophytes (common name)
-include liverworts,hornworts & mosses
-adaptation-embryophyte condition
-gametes develop w/in gametangia(male
gametangium,antheridium,flagellated,female
gametangium,/archegonium,1 ovum made)
-Egg fertilized & zygote develops into an embryo w/in
archegonium
-need water to reproduce
-Most have no vascular tissue to carry water from soil
to aerial parts of plant
-(as water moves over surface)Most must imbibe water
like sponge & distribute it thoughout plant by
diffusion, capillary action, & cytoplasmic streaming
-Life cycle has alternation of haploid & diploid
generations
Division Bryophyta-Mosses
-many plants growing in a tight package helping to
hold each other up (mat of moss)
-has spongy quality enabling it to absorb & retain
water(mat of moss)
-each plant of mat grips substratum w/ elongate
cells/cellular filaments-rhizoids
-Most photosythesis occur in upper part of plant(has
many small stemlike & leaflike appendages.
-"stems", "leaves","roots"(rhizoids) (different from
structures in vascular plants)
Division Hepatophyta-Liverworts
-Less conspicious than mosses
-Some have bodies divided into lobes
-Some live in tropical forests
-Life cycle is like that of moss
-Some have sporangia that have coil-shaped cells
(spring out of capsule when it opens,help disperse
spores)
-Reproduce asexually from gemmae(little bundles of
cells)
Division Anthocerophyta-Hornworts
-Resemble liverworts
-Distingushed by sporophytes,elongated capsules
-Most closely related to vascular plants
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