biology lab final

Heterotrophic Organisms

Organisms that obtain nutrients from other sources; both animals and fungi.

Chitin

A polysaccharide that composes fungal cell walls and arthropod exoskeletons, indicating a close relationship between fungi and animals.

Mycorrhizal Fungi

Fungi that form a mutualistic symbiosis with plant roots, aiding in water and nutrient absorption.

Saprobes

Decomposers; fungi that play a crucial role in ecological nutrient cycles.

Mycelium

The main body of a multicellular fungus, typically underground, composed of a network of hyphae.

Hyphae

Thin, interconnected cytoplasmic strands that compose the mycelium of a fungus, providing a large surface area for absorption.

Yeasts

Single-celled fungi.

Dimorphic Fungi

Fungi that can alternate between yeast and mycelial forms; many fungal human pathogens are dimorphic.

Haplontic

A life cycle in which the majority of time is spent in the haploid state; typical of fungal life cycles.

Dikaryon

A unique fungal state (n + n) where two genetically distinct haploid nuclei exist in the same cell.

Plasmogamy

Cytoplasmic fusion between two individuals, preceding nuclear fusion in fungal sexual reproduction.

Karyogamy

Nuclear fusion, often following plasmogamy in fungal sexual reproduction.

Zygomycota

A fungal phylum (likely paraphyletic).

Ascomycota

A fungal phylum (monophyletic).

Basidiomycota

A fungal phylum (monophyletic).

Dikarya

A group including Ascomycota and Basidiomycota, also known as 'higher fungi' or 'crown fungi'.

Molds

Multicellular fungi consisting of tightly compressed hyphae; a descriptive term that includes certain zygomycetes and ascomycetes (polyphyletic).

Coenocytic hyphae

Hyphae lacking septa (cell walls) and thus possessing shared, syncytial cytoplasm.

Aseptate hyphae

Hyphae without cell walls.

Conidia

Asexual spores produced by molds.

Asci

Sac-like structures in ascomycetes where sexual spores (ascospores) are produced.

Basidia

Club-like structures in basidiomycetes where basidiospores are born externally.

Lichens

Symbiotic mutualisms between a Dikarya fungus and autotrophic microbes (cyanobacteria or green algae).

Cambrian explosion

The radiation of animals (metazoans) began approximately 550 million years ago during this event.

Opisthokont

The evolutionary ancestors to animals were a lineage of single-celled protists in this clade.

Monophyletic Clade

Animals are classified as this, meaning they have a single common ancestor.

Ingestive Heterotrophs

Animals obtain nutrition as this, consuming other organisms.

Asymmetry

The term for animals lacking a fixed point of symmetry.

Spherical Symmetry

The type of symmetry where body parts radiate from a central point, allowing for an infinite number of planes of symmetry.

Radial Symmetry

Animals with this type of symmetry have one main oral-aboral axis, common in diploblastic animals.

Bilateral Symmetry

Animals with this type of symmetry have one plane of symmetry along the body axis.

Cephalization

The evolutionary trend associated with bilateral symmetry, involving the concentration of nervous tissue and sensory organs at the anterior end.

Ectoderm

The outer germ layer in animal embryos, forming the skin and nervous system.

Endoderm

The inner germ layer in animal embryos, forming the lining of the gut and digestive organs.

Mesoderm

The middle germ layer in triploblastic animals, allowing for a diversity of tissues like muscles and skeletal elements.

Porifera (Sponges)

Animals in this phylum lack true tissues, organs or organ systems and filter feed using choanocytes.

Choanocytes

Specialized cells in sponges that use flagella to move water and capture food particles.

Spicules

Supportive endoskeletal structures found in sponges.

Nematocyst

The defining synapomorphy of cnidarians; a specialized stinging organelle.

Polyp and Medusa

The two body forms exhibited by cnidarians.

Pseudocoelomate

A body cavity not fully lined by mesoderm.

Coelomate

A true body cavity completely lined with mesoderm.

Acoelomate

Bilaterians without a body cavity.

Protostomes

These bilaterians development have the 'mouth first'.

Deuterostomes

These bilaterians development have the 'mouth second'.

Platyhelminthes

Phylum containing flatworms that are acoelomate.

Nematoda

Phylum containing roundworms that are pseudocoelomate.

Annelida

Phylum containing segmented worms that are coelomate.

Mollusca

Phylum that is characterized as soft-bodied.

Arthropoda

Phylum that is the most abundant and diverse.

Molting/Ecdysis

The periodic shedding of the exoskeleton of arthropods

Chelicerata

These arthropods include spiders, ticks, and scorpions.

Crustacea

These arthropods include crabs, lobsters, and crayfish.

Hexapoda

These arthropods include insects.

Myriapoda

These arthropods include centipedes and millipedes.

Echinodermata

Deuterostomes characterized by calcareous plates and a water-vascular system.

Phylum Chordata

A major group of bilaterians in the deuterostome clade, including vertebrates, cephalochordates, and urochordates.

Synapomorphic Characters

Present during at least part of the life of every chordate.

Vertebrates

Articulated spine or vertebral column providing strong support for a larger, more mobile organism.

Cranium

A part of the overall bony structure enclosing the brain.

Fish

Aquatic vertebrates with scales, paired fins, unpaired fins, and gills.

Scales

Protective layer of imbricated structures covering most fish.

Cycloid and Ctenoid Scales

Thin leptoid scales found in most teleost fish.

Cycloid scale

Found in teleosts with soft fin rays, such as salmon, trout and carp

Ctenoid (toothed) scale

Found in teleosts with spiny fin rays, such as perciformes (perch, sunfish)

Gill Arches

Structures that support gill filaments.

Gill Filaments

Highly branched structures for gas exchange in fish gills.

Tetrapods

Vertebrates that transitioned onto land.

Amphibian

Anamniote vertebrate, such as the northern leopard frog.

Glottis

Opening to the trachea.

Diaphragm

A sheet of skeletal muscle that separates the thoracic cavity from the abdominopelvic cavity in rats.

Descriptive Statistics

Characterizes data.

Inferential Statistics

Determines statistical significance, such as t-test.

Mean

The arithmetic average.

Median

The midpoint of the data set.

Mode

The most common value of the data set.

Range

Difference between maximal and minimal values of data set.

Variance

A statistic based on deviations from the mean.

Standard Deviation

The square root of the variance.

Chi Square Test

A form of inferential statistics used to compare observations in discrete categories to see if the pattern is different than random chance.

Null Hypothesis

Predicts no difference between groups across categories.

P-value

The probability of obtaining results as extreme as, or more extreme than, the observed results of a statistical hypothesis test, assuming that the null hypothesis is correct.

Pleon

The abdomen of an isopod.

Pleotelson

The fused last segment of the isopod abdomen.

Pereon

The thorax of an isopod.

Cephalon

The head of an isopod.

Pill Bug

A type of woodlouse that can roll up into a sphere for protection.

Sow Bug

A type of woodlouse that cannot roll up into a sphere and relies on its exoskeleton for protection; genus Porcellio

Embrophyta

The plant clade. Land plants are the foundation of terrestrial life and arose from a lineage of freshwater multicellular green algae.

Streptophyte

The green algae that most closely resembles terrestrial land plants, sharing features like chlorophylls a and b, starch energy storage, and cell walls of cellulose and pectin.

Viridiplantae

The clade including all green algae and land plants.

Alternation of Generations

A conserved sexual life cycle pattern in all land plants, involving two alternating multicellular forms: diploid sporophyte (2n) and haploid gametophyte (n).

Sporophyte

The diploid (2n) multicellular form in plants that undergoes meiosis to produce haploid spores, which develop into gametophytes.

Gametophyte

The haploid (n) multicellular form in plants that produces gametes via mitosis.

Gametangia

Organs inside of which gametes are produced.

Sporangia

Organs inside of which spores are produced.

Cuticle

A waxy coating on land plants that slows water loss.

Stomata

Openings in stems and leaves of land plants that regulate gas exchange and conserve water.

Vascular Tissue

Plant tissue for transport and support.

Bryophytes

Informal taxonomic designation for early seedless non-vascular plants like liverworts, mosses, and hornworts.