Characteristics of Living Things and Species Concepts

All living organisms possess seven essential characteristics: growth, reproduction, adaptation, metabolism, movement, irritability, and cellular structure.

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

Different ways scientists define species, due to limitations in identifying and classifying certain types of species.

A species is defined by its physical characteristics (shape, size, and structure).

A species is defined by its ability to interbreed and produce viable, fertile offspring in nature.

Species are defined by their evolutionary relationships.

Simplicity and wide application, especially for plants; readily observable characteristics.

Difficulty in determining the degree of difference between organisms to differentiate them as separate species; overlooking important differences.

Two-word Latin name for each species, used in classifying organisms. It includes the genus (first word, capitalized) and species (second word, lowercase).

The science of identifying, naming, and classifying species.

A system of categorizing organisms from very broad groups to very specific groups based on shared characteristics.

A shared ancestor from which different species have evolved.

Comparing body structures (anatomy) to learn about evolutionary relationships among species.

A system for classifying organisms into a hierarchical structure based on shared characteristics developed by Carolus Linnaeus.

Grouping organisms based on shared characteristics.

Levels in the hierarchical classification system (e.g., domain, kingdom, phylum).

HIV inserts its genetic material into the host cell's DNA, creating a provirus that can remain dormant for a long time. The cell then makes new HIV viruses without showing symptoms.

Prions are infectious proteins, causing diseases by converting normal proteins into misfolded, harmful versions. This process spreads the abnormal proteins.

Viruses can be used as tools to insert or copy genes into cells. They naturally inject genetic material into cells.

Viruses, unlike bacteria, are not affected by antibiotics which target bacteria.

Archaea that produce methane gas during the anaerobic breakdown of organic materials. These microbes are found in environments lacking oxygen.

Microorganisms that thrive in extremely hot environments.

Archaea that live in very salty environments.

Photosynthetic bacteria that produce oxygen.

A substance found in bacterial cell walls, but not archaea cell walls.

Bacteria with thick peptidoglycan walls that retain the crystal violet stain.

Asexual reproduction method in prokaryotes, where a cell divides into two identical cells.

Spherical-shaped bacteria.

Bacteria with thin peptidoglycan walls that do not retain the crystal violet stain.

When a cell grows to a certain size, it lengthens and separates the original and copied chromosome, preparing for cell division.

A process where two bacterial cells transfer genetic material by directly linking.

Small, separate loops of DNA that contain genes and can move between cells.

Dormant bacterial cells that survive harsh conditions by forming thick protective walls.

A bacterium that produces a deadly toxin, often found in improperly canned foods.

A bacteria responsible for strep throat infections.

Bacteria in our gut help with the immune system, produce vitamins and prevent harmful bacteria/tumors.

Bacteria that break down organic matter, releasing nutrients back into the environment.

A technique used to make millions of copies of DNA using an enzyme from archaea that can withstand high temperatures.

The theory explaining how eukaryotic cells evolved from symbiotic relationships between prokaryotic cells, where one cell engulfs another, and the engulfed cell survives and becomes an internal part of the engulfing cell.

Organelles found in photosynthetic eukaryotes that convert solar energy into sugar.

Organelles that extract energy stored in sugar so the cell can perform work.

A cell that is engulfed by another cell in the process of endosymbiosis.

The cell that engulfs another cell in the process of endosymbiosis.

Similarities in membranes with living prokaryotes, ribosomes that are more similar to prokaryotic ones, reproduction via binary fission, circular chromosomes, and matching gene sequences.

The state of being composed of multiple cells that work together, with specialized functions.