Incomplete - 10 - Classification and evolution Flashcards
Why is there a standardised system for classification?
- same language
- identify new species
- evolutionary links
What is a species?
a group of similar organisms with certain features in common and similar genes
capable of naturally interbreeding and producing fertile offspring
What is the name for the classification system we use?
phylogenetic classification
How is the classification system organised?
by how closely they are related
what is the order to the taxonomies in classification?
kingdom phylum class order family genus species
As you go down the classification system what happens to the number of organisms and the similarities?
fewer organisms, greater similarities
how do we write the binomial nomenclature of a species?
genus + species
capital for genus, italics for species
Name the 5 kingdoms in the 5 kingdom system?
prokaryotae Protoctista fungi Plantae animalia
Name the 3 domains in the 3 domain system
bacteria, archaea, eukarya
name the 6 kingdoms in the 3 domain system
eubacteria, archaebacteria, protoctists, plantea, fungi, animalia
define autotrophic
an organism that obtains its nutrients itself ie. via photosynthesis
define heterotrophic
an organism that obtains its nutrients from ingesting other organisms
define saprotrophic
an organism that secretes extracellular enzymes ad absorbs soluble molecules to obtain its nutrients
What did Woese study to come up with his 3 domain system?
- ribosomal RNA sequences
- membrane lipid structure
- sensitivity to antibiotics
Describe the features of a prokaryote in terms of:
- cell wall
- genetic material
- nutrition
- motility
peptidoglycan
circular DNA (not membrane-bound, no histones or chromosomes)
absorbs nutrients from its surroundings - diffusion
some move with a flagella
divide by binary fission
Describe the features of a Protoctista in terms of:
- cell wall
- genetic material
- nutrition
- motility
- no cell wall
- DNA in the nucleus
- some autotrophic some heterotrophic
- flagella, pseudopods or cillia
- eukaryotic and unicellular
Describe the features of fungi in terms of:
- cell wall
- genetic material
- nutrition
- motility
- DNA in the nucleus
- chitin cell wall
- sapprophitic, store as glycogen
- no motility
- reproduce by spores (either sexual or asexual reproduction)
Describe the features of a plant in terms of:
- cell wall
- genetic material
- nutrition
- motility
- DNA in nucleus
- cellulose cell wall
- autotrophic, store as starch
- no motility
- eukaryotic
Describe the features of an animal in terms of:
- cell wall
- genetic material
- nutrition
- motility
- DNA in nucleus
- no cell wall
- heterotrophic, most have gut, store as glycogen
- motility through muscles and nervous systems
- eukaryotic
2 descendants on a phylogenetic tree split directly from same node are called…
sister groups
nodes/ where lines join on a plhylogenetic tree represent
common ancestors
What does an extinct species look like on a phylogenetic tree?
a line that does not continue to the present (often perpendicular to line of time)
How do different species evolve?
mutations in dna
leads to change in gene
COULD cause a change in phenotype if different amino acid is produced
Why do mutations not always change the phenotype of a species?
DNA is degenerate code
change in base could lead to the same amino acid
