Diversity Unit Notes

Prokaryotic

Cells that do not have a membrane-bound nucleus or organelles; examples include Bacteria and Archaea.

Eukaryotic

Cells that have a membrane-bound nucleus and are larger and more complex than prokaryotic cells.

Domain

The largest taxonomic unit, consisting of three groups: Bacteria, Archaea, and Eukarya.

Species Diversity

The variety and abundance of species in a given area.

Genetic Diversity

The variety of heritable characteristics (genes) in a population.

Ecosystem Diversity

The variety of ecosystems within a biosphere.

Capsid

The outer layer that surrounds the genetic material of a virus.

Endosymbiosis

The theory that explains how eukaryotic cells evolved from a symbiotic relationship between prokaryotic cells.

Binary Fission

A form of asexual reproduction in which a single cell divides into two genetically identical cells.

Lytic Cycle

The replication process in viruses where the virus's genetic material uses the host cell to make new viruses.

Lysogenic Cycle

A viral reproduction cycle in which the viral genome integrates with the host genome without killing the host cell.

Gram Positive

Bacteria that retain the gram stain and appear purple due to a thick peptidoglycan cell wall.

Gram Negative

Bacteria that do not retain the gram stain and appear pink, having a thin peptidoglycan cell wall and an outer membrane.

Autotroph

Organisms that produce their own food, often through photosynthesis.

Heterotroph

Organisms that obtain nutrients and energy by consuming other organisms.

Dichotomous Key

An identification tool consisting of a series of two-part choices that lead the user to a correct identification.

Morphological Species Concept

A classification based on structural features of organisms.

Species

A group of organisms that can interbreed in nature and produce fertile offspring.

Phylogenetic Trees

Diagrams that depict the evolutionary relationships among species.

Gametophyte

The haploid phase in the alternation of generations that produces gametes.

Sporophyte

The diploid phase in the alternation of generations that produces spores.

Mycelium

A mass of fungal filaments or hyphae that forms the main growing structure of a fungus.

Plantae

The kingdom that includes multicellular autotrophic organisms (plants) that perform photosynthesis.

Animalia

The kingdom that includes multicellular heterotrophic organisms (animals) that do not have a cell wall.

Chloroplast

An organelle found in plant cells that converts solar energy into chemical energy through photosynthesis.

Mitochondria

An organelle that extracts energy from stored sugar in eukaryotic cells.

Bacteriophage

Viruses that infect bacteria.

SARS-COVID-19

A virus specific to the respiratory tract, causing COVID-19 disease.

HIV

A retrovirus that is dormant and attacks T-cells.

Ecosystem Services

The benefits that humans freely gain from the natural environment and from properly-functioning ecosystems.

Pseudopods

Temporary projections of the cell membrane used for movement and feeding, characteristic of amoeboid cells.

Chitin

A structural polysaccharide found in the cell walls of fungi.

Cellulose

A carbohydrate that forms the structural component of plant cell walls.

Peptidoglycan

A polymer that forms a protective layer in the cell walls of bacteria.

Retrovirus

A type of virus that transcribes its RNA into DNA after infecting a host cell, such as HIV.

Gymnosperms

Seed-producing plants that have seeds unprotected by an ovary or fruit.

Angiosperms

Seed-producing plants that produce seeds enclosed within a fruit.

Monocots

Angiosperms that have one seed leaf, or cotyledon.

Dicots

Angiosperms that have two seed leaves, or cotyledons.