Species + Taxonomy Flashcards
What is a species?
- a group of similar organisms that can breed to produce fertile offspring
What must species do to survive?
- reproduce + pass on advantageous alleles
What is courtship?
- a behaviour essential for successful mating + species recognition
What is a courtship ritual?
- a sequence of actions, usually performed by males, that’s unique to each species
- how animals identify members of their own species to reproduce w - female observes ritual + decides if they want to mate w male
What are some examples of courtship rituals?
- a sequence of:
- dance moves
- sounds
- pheromone release
- display of colourful feathers
- fighting
What is the importance of courtship rituals?
- ensures successful reproduction
- enables them to recognise own species + opposite sex
- synchronises mating behaviour: as indicates if female is sexually mature + in season (releasing egg)
- ensures survival of offspring
- form a bond pair
- choose a strong + healthy mate
What do courtship rituals show?
- how closely related a species is: more similar a courtship ritual is between diff species = more closely related
- rituals are genetically determined so species w similar sequence have a similar DNA base sequence
What is taxonomy?
- the practice of biological classification
How does the phylogenetic classification system work?
- uses a hierarchy to arrange species into groups, called taxa, based on their evolutionary origins + relationships
- tells us who’s related + how closely related they are
- a phylogenetic tree shows all organisms have evolved from shared common ancestors
What are the ways organisms are classified into groups?
- originally based on visible similarities (e.g. appearance, behaviour)
- more modern + accurate methods are:
- DNA sequence
- mRNA sequence
- AA sequence
- Immunological: comparing similarity in self-antibody shape
What are the 3 types of domain?
- archaea (prokaryotes)
- bacteria (prokaryotes)
- eukarya (eukaryotes)
What is the definition + purpose of a hierarchy in classification systems?
- smaller groups arranged within larger groups w no overlap between groups
- helps understand relationship between organisms + keeps track of changes
- needs to be universal
What is the order of taxonomic ranks (from higher to lower rank) that make up a hierarchy?
- Domain
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
What are binomials?
- scientific name for a species: allows it to be universally identified
- 1st name is its genus, 2nd name is its species
- written in italics + only 1st name has a capital letter
- species w same genus = close relationship
Why do some different species look similar?
- live in a similar envi., so are exposed to similar selection pressures
- similar alleles will have selective advantage + will produce similar/same proteins so have similar characteristics
What has helped to clarify evolutionary relationships between organisms?
- advances in genome sequencing + immunology
How has advances in genome sequencing helped clarify evolutionary relationships between organisms?
-
sequencing tech can use sequence data (DNA, RNA, AAs) to determine order of DNA/mRNA bases + AAs within an organism’s genome
- useful for comparing extinct species + distinguishing between physically similar species
- more similar the sequences, the more closely related the species are
How has advances in immunology helped clarify evolutionary relationships between organisms?
- allows scientists to use immunological techniques to compare proteins of organisms
Describe a method of an immunological technique that helps clarify evolutionary relationships between organisms.
- extract albumen from blood samples taken from diff. species + inject each pure albumen sample into diff. rabbits
- specific antibodies (to each albumen) from rabbits are extracted + mixed w diff. albumen samples
- pptn from each mixed sample is weighed
- larger weight = antibody + albumen more complementary
