Bio 300 Lab Practical Midterm

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