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Flashcards in Classification (UNIT 2) Deck (11):
1

Species

Similar to one another but different from members of other species.

Capable of breeding to produce living, fertile offspring.

2

What do members of the same species have in common?

Similar genes so similar physical and biochemical properties. Similar patterns of development and similar immunological features and occupy same ECOLOGICAL NICHE.

3

Naming Species- THE BINOMIAL SYSTEM

Two names.
UNIVERSAL
1st name- generic, denotes GENUS to which organism belongs. UPPERCASE

2nd name- specific name, denotes the SPECIES to which organism belongs (NEVER SHARED WITH ANOTHER SPECIES) LOWERCASE

PRINTED IN ITALICS or underlined if written.

4

CLASSIFICATION

The grouping of organisms

5

TAXONOMY

The theory and practice of biological classification.

6

Two main forms of biological classification.

ARTIFICIAL CLASSIFICATION- divides organisms according to differences that are useful at the time. E.g. colour, size, number of legs, leaf shape etc.
NATURAL CLASSIFICATION-
-based on evolutionary relationships between organisms and their ancestors.
-Classifies species into groups using shared features derived from ancestors
-arranges the groups into a hierarchy.

7

HOMOLOGOUS CHARACTERISTICS

SIMILAR EVOLUTIONARY ORIGINS.

8

Order of classification of organisms.

KINGDOM
PHYLUM
CLASS
ORDER
FAMILY
GENUS
SPECIES

9

PHYLOGENY

The evolutionary relationship between organisms
The phylogeny of an organism reflects the evolutionary branch that led up to it.

10

Why are there difficulties in defining a species? (6)

-Species are not fixed but change and evolve over time. Some may develop into new species.
-Considerable variety within a species. eg dogs.
-Many species are extinct and most leave no fossil record.
-Some species rarely reproduce.
-Members of different groups of the same species may be isolated. May be classified as different species.
-Some species are sterile

11

What are ANALOGOUS CHARACTERISTICS

Characteristics that have the same function but different evolutionary origins