Biology Chapter 1: Classifying Life's Diversity

Body shape, size and other structural features.

+ simple, widely used
- deciding how much difference between individuals is too much

Whether 2 organisms can produce fertile offspring. If so, the 2 organisms are the same species.

+ widely used
- can't be applied in all cases (don't have the chance to breed or to organisms that reproduce asexually)

Evolutionary relationships/history among organisms.

+ can be applied to extinct species
- not known for all species

The branch of biology that identifies, names and classifies species based on natural features

two-part Latin naming system

- 1st word is genus (capitalized)
- 2nd word is species
- italicized when typed, underlined when handwritten

Grouping of organisms based on set of criteria

A level in a classification scheme
Ex. phylum

Named group of organisms
Ex. phylum Chordata

The structure of an organism

Ex. bird and dinosaur have similar bones and feathers

Biochemistry of an organism
- proteins are compared to determine genetic similarity or difference

Ex. guinea pig insulin is way different than other rodents

Genetic analysis
- comparison of nucleotide sequences

Ex. fungi and animals are most closely related than fungi and plants

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

- to assign species to taxa reflected to the morphological and phylogenetic similarities

- achieved by using concept of shared evolutionary history (the most species share an ancestor, the more closely related they are)

- helps them understand how an organism develops and functions structurally

- determines evolutionary relationship among species

- scientists can track down sources of a drug they need

- helps trace transmission and develop treatments

-incase of invasive species, biological control can be used with knowledge of different taxa