Units 1-6
Anabaena
Photoautotrophic, nitrogen-fixing bacteria. Nitrogen fixation occurs at heterocyst sites. Cyanobacteria. Endosymbiont of Azolla
Phylogenies
The history of the evolution of a species or group, especially in reference to lines of descent and relationships among broad groups of organisms. Graphic representation of hypothesized evolutionary relationships
Clade
Monophyletic group; common ancestor and ALL descendants; a branch of a phylogenetic tree
Common ancestor
The shared ancestor of species that have shared traits
Taxon/ taxa
Any named group of organisms
Node
Represents the common ancestor of two descendant taxa
Plesiomorphy
Ancestral trait
Apomorphy
Derived traits that are specific to a single species
Synapomorphy
Shared derived traits that are shared by 2 or more species
Autapomorphy
Synonymous with apomorphy most of the time: derived trait that is unique to the terminal group of a phylogenetic tree
Ingroup
The group of organisms that is being studied
Outgroup
The group outside the group in question - used as a comparison point
Root
Common ancestor of a phylogenetic tree from which all descendant taxa are derived.
Sister groups
two descendants that are derived from a common ancestor and are each others closest relative
Prokaryotic background
The origin of life was 3.5 bya; eukaryotes evolved 1.5 bya; prokaryotes assumed the role of producers, consumers, decomposers; first evolved as anaerobes; O2 revolution was 2.5 bya
Facultative vs. obligate
Facultative: not stuck to one state
Obligate: can only work under certain conditions
Photoautotroph
Photosynthetic organisms
photoheterotroph
Organisms that feed by making food using light, then consume the food molecules
Chemoautotroph
An organism that feeds itself by extracting energy from chemicals
Chemoheterotroph
An organism that feeds by making food using chemicals, then consumes the food molecules
Bacillus
Rod shaped bacteria; can come as a single rod or chain arrangement
Coccus
Spherical shaped bacteria; can come as chains, clusters, pairs, or singles
Spirillum
Spiral bacteria that can come as a spiral or corkscrew arrangement
Diplo-
A prefix used to describe bacteria that occur in pairs. Examples include diplococcus, which refers to spherical bacteria found in pairs.
Staphylo-
A prefix used to describe bacteria that occur in clusters or bunches, such as staphylococcus, which refers to spherical bacteria found in clusters.
Strepto-
A prefix used to describe bacteria that occur in chains, such as streptococcus, which refers to spherical bacteria found in chains.
Tryptic Soy Agar
An unselective growth medium that supports a broad spectrum of bacteria
MacConkey’s Agar
Bile salts and crystal violet growth medium that selects against gram positive bacteria - considered semi selective
Sulfadiazine
Blocks production of essential nutrients that bacteria require; very selective growth medium because most gram positive and some gram negative are affected.
Tetracycline
Growth medium that represses protein synthesis in all bacteria - the most selective
Halobacterium Salinarum
A type of archaea that’s an extreme halophile (tolerates high salt concentrations)
photoheterotroph
contains a pigment called bacteriorhodopsin that is a non-photosynthetic, light harvesting pigment
doesn’t fix CO2 like most plants
consumes amino acids or other organic acids
simple stain
Paramecium
large, unicellular, heterotrophic
protist
easy to see nuclear envelope and digestive vacuoles
Will draw food into the oral groove and enclose food in vacuoles
Euglena
Belongs to excavates
Be able to label chloroplasts and flagellum
Male Fucus Conceptacle
Fucus belongs to stramenopiles - brown algae - does alternation of generations
Be able to label the conceptacle wall, antheridium, and sperm location
Female Fucus Conceptacle
Be able to label the conceptacle wall, oogonium, and egg location
Trichonympha
Unicellular
Belongs to excavates
Termite endosymbiont - produces the enzymes that degrade cellulose to help termites digest wood
Saprolengia
Belongs to oomycetes in stramenopiles clade
Not a fungus but looks and behaves like one - multicellular - saprobic (parasitic)
Responsible for Irish potato famine
Body is a mass of cell width filaments called hyphae
Multiple nuclei in a single plasma membrane (coenocytes)
Reproduces via oogonium
Be able to label hyphae and oogonium
Foraminifera
Belongs to rhizaria
Marine chemoheterotrophs
Deposits of CaCO3
Moves carbon to deep-sea sediments
Pseudopods extend out to cast sticky net and catch food
Label the calcium carbonate shell
Diatoms
Belongs to stramenopiles clade
Photosynthetic
Red algal secondary endosymbiosis
Unicellular and aquatic
Shell made from silicon dioxide (SiO2)
Appearance is coincident with grass evolution due to increase of Si from grassland runoff
Label the silicon dioxide tests
Prokaryotes
Bacteria and archaea
Small in size (usually unicellular)
No nucleus - single loop of DNA
Few to no organelles
Limited structure (has a cytoskeleton and microtubules)
Eukaryota
A domain that includes protists, fungi, plants, and animals
Eukaryotic cell components
Membrane-bound nucleus that houses DNA
Specialized organelles
Plasma Membrane
Cell walls (only some)
Protist
Any eukaryote lineage that is not a land plant, animal or fungus - will fall into 1 of 3 categories: plant-like, animal-like, or fungal-like
Most are microscopic
Most are single-celled but can be multicellular
Can be autotrophic or heterotrophic
Can reproduce sexually or asexually
Can move via cilia, flagella, or pseudopodia
PARAPHYLETIC group
Physarum polycephalum
Belongs to the plasmodial slime mold clade (part of Amoebozoan supergroup)
move hydrostatically via pseudopods
Feeding and movement is primarily through chemotaxis (sensing chemical gradients)
Can change into sclerotineum (resting state) in poor conditions
Does complex decision-making despite the lack of an information processing center (makes feeding decisions based on quality and quantity, remembers where it’s been, finds optimal pathways to food)
Does sporic meiosis
Chlamydomonas
Motile, unicellular, and freshwater type of chlorophyte
Volvox
Type of chlorophyte
Motile colonial green algae - hundreds to thousands of haploid cells in a gel matrix
Asexual reproduction - vegetative with daughter colonies forming inside parent colonies
Sexual reproduction - at the end of the growing season forms gametes; dormant zygotes undergo meiosis before germination
Spirogyra
Type of chlorophyte
Freshwater green algae
Reproduce via conjugation (bacterial sex) resulting in diploid zygotes
Chara
Type of chlorophyte
Freshwater green algae
Develop CaCO3 on their cell walls
“Stonewart”
Most closely related group of green algae to land plants - evidenced by genetic data
Marchantia Antheridium
Houses male gametes (flagellated sperm)
Breaks open to allow sperm to swim away (or disperse in rain drops)
Marchantia
Liverworts
Non-vascular plant
Thallus made up of flat tissue
Mostly haploid gametophytes
Pores on the upper surface allow for gas exchange but aren’t true stomata b/c they lack guard celld
Asexual reproduction via Gemma cups (water droplets splash out of the Gemma cups and disperse - produces clones of the parent)
Marchantia Archegonial Head
Houses female gametes (egg cells)
Produces multicellular sporophyte (2n) when eggs are fertilized
Sporophyte is attached to and nutritionally depend on the female gametophyte
Mosses
Non-vascular plant
Produces a non-photosynthetic sporophyte which is nutritionally dependent upon the gametophyte
Sporophyte forms sporangium
Produces haploid spores
Moss protonema
Thread-like chain of cells that will develop into gametophore
Moss Sporangium
Spore capsule
Where haploid spores are produced.
This image is a polytrichum
Ceratopteris Richardii
Leptosporangiate fern native to tropical wetlands
Reaches sexual maturity in 2 weeks
Secretes antheridogen which controls differentiation of either male or hermaphrodite sexual forms
Has natural genetic mutants that can be compared to the wild-type to illustrate important points about plant structure or function
Has polka dot or wild type
Adaptations to water scarcity
Cuticle, stomata, spore, and vascular tissue formation
Adaptations plants made to access sunlight on land
Structural support through lignified vascular tissues
Primary growth
Branching apical growth; responsible for vertical growth
Apical meristems
Growth through cell division in mitotic zones which are located in apices of the plant
Axillary bud
meristematic tissue laid down by shoot apical meristem at the node between the stem and eventual leaf
3 Functional groups that result from primary tissue development
Dermal (epidermis)
Ground (mesophyll) - fill spaces between dermal and vascular tissue; parenchyma, collenchyma & sclerenchyma
Vascular (xylem and phloem)
Coleus shoot tip
Zea Mays
Medicago stem
Secondary Growth
Increases lateral girth in stems and roots
Vascular Cambium
Secondary meristem
Appears between primary xylem and phloem
Generates new vascular tissue
Secondary Xylem
Grows toward the interior of stem
Annual rings
Spring wood - treachery elements are thinner walled
Summer wood - narrower, thicker walled treachery elements
Parenchyma rays - deliver photosynthates
Secondary Phloem
Grows toward the exterior of the stem
Tilia Stem
Xylem tissue
Carries water and dissolved ions from the roots upwards to the stem and leaves
Consists of parenchyma cells & fibers, and several specialized water conducting cells called treachery elements (tracheids and vessel elements)
Fiber cells add support but don’t conduct fluid
Phloem tissue
Transports photosynthates from leaves to other parts of the plant
Contains specialized cells associated with photosynthate transport (sieve elements and companion cells)
Lycophytes
Club mosses and relatives
Low growing plants, typically in moist, shaded environments
Often have moss-like appearance
Protostele
Lycophyte stems have an arrangement of vascular tissues
Central core of xylem tissue surrounded by a layer of phloem tissue
Lycophyte Leaves
Microphylls=small leaves of this type of plant
Not anatomically true leaves of this plant
Lack complex venation
Gapless connection to protostele
Lycopodium Strobili
Homosporous: composed of many densely packed leaves (sporophylls) with attached sporangia; sporangia spores are identical in size; shed spores will produce bisexual gametophytes
Heterosporous: megasporangia (larger spores that germinate into female gametophytes); microsporangia (smaller spores that germinate into male gametophytes)
Euphylophytes (Leptosporangiate Fern)
Include ferns and seed plants
Highly vascularized true leaves (megaphylls - leaf gap - defining feature of true leaf; reroutes vascular tissue into leaf)
Fern rhizome (has siphonostele: O or C shaped ring of vascular tissue)
Fronds
Name for fern leaves
Develop from spirally folded buds (fiddleheads)
May be divided or undivided into one to several levels of pinnae (leaflets)
Sporangia are borne either on undersurface of fronds or on highly modified, non-photosynthetic fronds (multiple sporangia are called sori)
Leaves
Principle organ of photosynthesis
Sunlight provides energy for photosynthesis, UV radiation and heat can impair metabolic functions and increase water loss
Environmental conditions have encouraged a variety of morphological and physiological adaptations
Petiolate leaf
When a leaf on a plant forms on a branch away from the plant stalk
Sessile leaf
When the leaf grows directly on the plant stalk
Mesomorphic
Moist adapted plants
Hydromorphic
Wet-adapted plants
Xeromorphic
Dry adapted plants
Spermatophytes
Angiosperms and gymnosperms are a major extant group of seed-bearing plants part of this group
Gymnosperms
Fruitless seed plants
Female gametophytes develop on the exterior of sporophyte plant body
No ovary; seeds are unprotected
Common plants that belong to this group include pine trees
Angiosperms
Basal, monocots, eudicots
Flower, fruit, double fertilization, endosperm