tree of life chapter 28-29, other groups of organisms phylogeny key lineages of prokaryotes Domain Archaea (sister to eukarya) 3 clades defined by genetic characters Domain Bacteria Firmicutes Spirochaetes Actinobacteria Chlamydiae Cyanobacteria Proteobacteria Bacteria Archaea morphology morphological diversity? highly conserved size most are quite small, the range is large shape filaments, cocci, bacilli, spirilla motility can swim with flagella, gliding movement gram stain cell wall composition gram staining not reliable for phylogeny represent differences in cell wall composition gram positive - high peptidoglycan composition in cell wall, usually lacking outer membrane gram negative - thinner peptidoglycan layer, usually with outer and inner membrane highly variable among clades gram positive cell wall plasma membrane gram negative outer membrane cell wall inner membrane peptidoglycan peptidoglycan
branches BACTERIA branches major branches in TOL Protista? paraphyletic / polyphyletic depends on perspective ARCHAEA EUKARYA BACTERIA ARCHAEA FUNGI ANIMALIA major branches in TOL Rhizaria Alveolata Stramenopila Amoebozoa Opisthokonta Excavata Plantae EUKARYA PLANTS branches BACTERIA major branches in TOL Rhizaria Alveolata Stramenopila Amoebozoa Opisthokonta Excavata Plantae BIKONTA UNIKONTA ARCHAEA AMOEBOZOA OPISTHOKONTA EXCAVATA PLANTAE RHIZARIA plant form chapter 36 ALVEOLATA STAMENOPILA
plantae classification (extant groups) Bryophytes Hepaticophyta (Hepatophyta) (liverworts) - Marchantia Anthocerophyta (hornworts) Bryophyta Vascular plants Pteridophytes Lycophyta Pterophyta Gymnosperms Ginkgophyta Gymnosperms -- cont. Cycadophyta (cycads) -Gnetophyta (gnetae) - Coniferophyta (conifers) --
Angiosperms Anthophyta -- monocots and eudicots Structure and growth of Angiosperms organs systems root system shoot system shoot root Plant tissues dermal tissue cuticle tissue xylem tracheids lignin vessel elements (tubes) phloem seive tube members companion cells tissue pith cortex (outside tissue) Dicot sclerenchyma phloem xylem tissue Monocot pith epidermis dermal epidermis bundle cortex dermal bundles
cell types in tissues parenchyma collenchyma sclerenchyma lignin fibers or sclereids (stone cells) roots root types monocots -- fibrous root system... dicots -- taproot function anchor the plant into the uptake of water from soil. storage of food molecules exchange of some nutrients structure -- variation prop roots buttress roots pneumatophores aerial roots storage roots root hairs
root tips root cap -- suberin (lipid) meristem (zone of division) -- quiescent center -- primary meristems: protoderm meristem procambium zone of elongation Key to labels Dermal Ground Vascular Epidermis Root hair Apical meristem Cortex Vascular cylinder Zone of differentiation Zone of elongation Zone of cell division zone of differentiation epidermis cortex stele () endodermis pericycle monocots -- tissue types in concentric rings Root cap 100 µm epidermis dermal cortex endodermis stele dicots a bit more organized, or at least centralized... starch storage same basic tissue types no pith xylem in center surrounded by phloem bundles pericycle surrounds phloem pericycle phloem xylem pith
Shoot system stems nodes internodes apical meristem axillary bud terminal bud modifications stolon (runner) rhizome bulb tubers leaves blade stalk petiole. venation parallel -- monocots reticulate -- dicots simple leaves vs. compound leaf some leaves serve other functions: leaves anatomy two layers of epidermis (top and bottom) dicots - two layers of mesophyll simple compound double compound
anatomy spongy mesophyll palisade mesophyll stomata water loss gas exchange cuticle? growth life history of plants -- indeterminate growth annuals -- life cycle completed in a year biennials -- life cycle spans two years -- overwinter perennials -- live for many years types of Growth -- primary growth secondary growth Secondary Growth lateral growth cambium secondary xylem tree rings secondary phloem pith primary xylem primary phloem growth secondary xylem secondary phloem cork bark cork cambium
Bark = periderm and phloem periderm cork cambium rings in trees Growth ring Vascular ray Heartwood Secondary xylem Sapwood Vascular cambium Secondary phloem Bark Layers of periderm