B&E Exam 2 Codon Vocab

Endosymbiosis

One organism living inside the cells of another

Mutualism

A relationship between two species that is mutually benficial, meaning that it increases the fitness of both

Alga

Any photosynthetic organism that lives in an aquatic environment. This is a catchall term that includes organisms from many different lineages

Protist

Any eukaryote that is not a fungus, animal, or land plant

Plasmid

A small, extrachromosomal loop of DNA. Many of the best-studied carry genes for antibiotic resistance

Peptidoglycan

A structural carbohydrate found in vacterial cell walls. It is a lattice made of sugars linked with β-(1,4)-glycosidic bonds that have short chains of peptide-bonded amino acids protruding from them

Prokaryote

Bacteria and archaea—organisms whse cells lack a nucleus

Microbe

Viruses and any microscopic organism—including bacterial, archaean, and eukaryotic species

Primary Producer

An organism that produces its own food, usually via photosynthesis. These are the source of the chemical energy and carbon compounds that all other organisms rely on for food

Microbiome

The collection of microbes that lives in a particular location

Phylogentic tree

A graphical depiction of evoluntionary history, or phylogeny

Homologous traits

Any characteristic, ranging from a single nucleotide in DNA to body parts, that is observed in multiple species and inherited from the same common ancestor

Root (of a phylogenetic tree)

The base of a tree, indicating the common ancestor of all the taxa indicated at the tips

Node (of a phylogenetic tree)

A split where a speciation event occurs, so one species splits into two. Also represents the last common ancestor before a speciation event

Branch (of a phylogenetic tree)

A species or other group changing through time

Tip (of a phylogenetic tree)

The end of a branch, representing a taxon

Taxon

A named group of organisms (plural is taxa)

Monophyletic group

An ancestor and all of its descendants

Synapomorphy

A trait that one group has that no else does. Synapomorphies define monophyletic groups

Homoplasy

Similarity in traits that is not due to common ancestry but due to independent evolution

Outgroup

Any lineage that is not part of the monophyletic group that is the focus of a phylogenetic tree

Parsimony

A criterion in logic that states that the simplest explanation is the most likely to be correct.

Parasite

An organism that takes resources from a host individual, reducing its fitness

Virion

An individual virus particle

Enveloped Virus

A virus with a surface comprised of a lipid bilayer studded with viral proteins

Non-enveloped virus

A virus with surface comprised of a protein coat (naked)

Protease

An enzyme that catalyzes breaking peptide bonds in a long string of amino acids. Some function as digestive enzymes; other break long amino-acid chains at specific points to create several to many independent proteins

Biomass

The mass of living organisms, usuallty in reference to a specific area or group

Cuticle

A waxy layer on the external surface of stems and leaves in the shoot system

Stomata

Regulated openings in leaves where gas exchange occurs (the singular form of the term is stoma)

Alternation of generations

A life cycle that has both multicellular diploid and multicellular haploid forms

Sporophyte

The multicellular haploid phase in a life cycle with alternation of generations

Spore

A single cell that is produced by meiosis and that germinates and grows into a multicellular individual by mitosis

Vascular tissue

Groups of cells specialized for transporting water, mineral nutrients, chemical signals, and sugars throughout the plant body

Pollen

A male gametophyte surrounded by a protective coat

Pollination

Transfer of pollen to an egg producing structure; often a mutualistic relationship based on plants accomplishing fertilization in exchange for animals obtaining food in the form of nectar or pollen

Seed

An organ comprised of an embryo and a food supply surrounded by a protective coat

Flowers

Organs that enclose the reproductive structures of angiosperms and are specialized for facilitating pollination

Fruits

Organs that enclose seeds and are specialized for facilitating dispersal

Primary productivity

In most ecosystems, the amount of light energy captured by photosynthetic organisms

Gross primary productivity

The total amount of primary productivity in an area, often reported as a rate with units of g/m²/year.

Net primary productivity

The amount of primary productivity present in biomass, often reported as rate with units of g/m²/year.

Human appropriation of net primary productivity (HANPP)

The amount of primary productivity used by humans, often reported as a rate with units of gigatons of carbon per year

Trophic level

The level at which a particular species feeds, starting with primary producers and moving on to primary consumers, secondary consumers, and so on.

Sink

A long term repository where a particular atom or molecule may remain for millions to hundreds of millions of years.

Denitrification

A collection of metabolic processes in different bacteria and archaea species that results in the release of N₂ as an end product. Analogous reactions release N₂ when biomass burns during wildfires

Flux

The rate that a substance moves, its direction and amount per unit time

Dead zone

A region of oxygen-free (anoxic) ocean water created by a chain of events that starts with over-fertilization with nitrogen.

Yeast

Any single-celled fungus

Chitin

A structural carbohydrate found in the cell walls of fungi (and the exoskeletons of insects, along with other structures in other species)

Mycelium

The body type found in multicellular fungi, comprised of a network of branching filaments called hyphae

Hyphae

The filaments that make up a fungal mycelium

Ligin

A complex, exceptionally stiff and strong macromolecule that is a key component of wood

Mycorrhizae

Fungi that live in association with plant roots and exchange mineral nutrients they acquire for sugars produced by photosynthesis

Muscle

An animal tissue comprised of cells that are packed with long actin fibers that shorten and lengthen in response to force supplied by myosin motor proteins

Nerve

An animal tissue comprised of cells called neurons, which process and transmit information throughout the animal body in the form of electrical signals

Multicellular

Having a body consisting of cells that are physically attached to one another, and that have distinct structures and functions that are specialized and complementary

Radial symmetry

Having a body with many planes of symmetry

Bilateral symmetry

Have single plane of body symmetry

Cephalization

The organization of the body into distinct head and tail regions, with a head specialized for sensory processing and the tail specialized for movement.

Choanocyte

A “collar cell” that is unique to sponges and that functions in creating water currents for filter feeding

Cilla

Many small projections from a cell that beat back and forth and aid in movement for the cell or material around the cell

Cnidocyte

A stinging cell that is unique to cnidarians (jellyfish et al.) and that functions in prey capture

Coelom

A body cavity that is lined with muscle and connective tissue and that functions as a hydrostatic skeleton in many species

Hydrostatic skeleton

A structure used in support and movement, created by the pressure of muscles pushing against body fluids that are enclosed in a defined volume — often a coelom

Metamorphosis

A change in body form that accompanies the transition from a sexually immature juvenile or larva to a sexually mature adult

Model organism

A study organism that is easy to work with and that serves as a model for many other organisms, meaning that results from experiments on that species hold for other species as well.