BIO 112 Exam 2 [Study Guide]

scientific name

A unique name given to an organism, consisting of two parts: the genus name (capitalized) and species name (lowercase), both italicized or underlined.

Linnaean classification hierarchy

A system to categorize organisms based on shared characteristics, including eight major levels: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Domain

The highest taxonomic rank that categorizes life into three major groups: Archaea, Bacteria, and Eukarya.

Kingdom

The second highest taxonomic rank that further divides domains into major groups such as Animalia, Plantae, Fungi, and Protista.

Phylum

A rank that groups organisms based on fundamental body plans and structural features.

Class

A more specific grouping within a phylum, categorizing organisms that share certain characteristics.

Order

Divides classes into smaller groups reflecting evolutionary relationships.

Family

A classification that includes closely related genera.

Genus

A group of species that are closely related and share a common ancestor.

Species

The most specific level of classification representing individual organisms that can interbreed and produce fertile offspring.

monophyletic group

An ancestor and all of its descendants, defined by shared derived traits (synapomorphies).

synapomorphy

Shared traits inherited from a common ancestor, helping to define monophyletic groups.

reversal

A process where a derived trait reverts to a more ancestral state, potentially confusing evolutionary interpretations.

convergence

The evolution of similar traits in unrelated lineages due to adaptation to similar environments.

Steno's Laws

Four principles used to interpret geological rock layers and establish relative dating.

Principle of Superposition

In a sequence of sedimentary rock layers, the oldest layer is at the bottom, with younger layers above it.

Principle of Original Horizontality

Layers of sediments are originally deposited horizontally, and any tilt or disturbance occurs later.

Principle of Original Lateral Continuity

Sediments are deposited in lateral layers that extend in all directions until they thin out or encounter a barrier.

Principle of Intrusive Relationships

Geological principle stating that sedimentary rocks are older than any igneous rock that intrudes into them.

Uniformitarianism

The principle that processes occurring in the present were similar to those that have operated in the past.

Cenozoic Era

The most recent geological era, known as the ‘Age of Mammals,’ spanning from 65 million years ago to present.

Mesozoic Era

The geological era known as the ‘Age of Reptiles,’ lasting from 251 to 65 million years ago.

Paleozoic Era

The geological era known as the ‘Age of Fishes,’ spanning from 543 to 251 million years ago.

adaptive radiation

A rapid evolutionary process where a single ancestral species diversifies into various new forms to exploit ecological niches.

serial endosymbiosis

The hypothesis that eukaryotic organelles such as mitochondria and plastids evolved from prokaryotic cells through a series of symbiotic events.

multicellularity

An organism composed of multiple specialized cells that function together as a single unit, usually originating from a single ancestor cell.

antibiotics

Medications that target specific bacterial processes to eliminate infections without harming human cells.

phylogenetic systematics

A method used to deduce evolutionary relationships and origins of species based on genetic sequences and shared characteristics.

photosynthesis

The process by which plants and some microorganisms convert light energy into chemical energy in the form of glucose, while releasing oxygen as a byproduct.

pollen grains

Plant male gametes encapsulated in a durable coat, allowing for fertilization without the need for water.

green algae

Aquatic organisms sharing characteristics with land plants, acting as a bridge in the evolution of terrestrial plant life.