4.3 Flashcards
What is biodiversity?
The variety of species that belong to every group of organism
What is a binomial name?
The binomial is made up of the organism’s genus name followed by the species name
How is the bionmial name made up?
The binomial is made up of the organism’s genus name (with a capital letter) followed by the species name (lower case)
What can be used to help identify organisms?
A dichotomous key
What is Dichotomous key?
Di -two
Dichotomous - cut
A key with questions that divide into 2 alternative answers
What is the order of the hierarchy?
Kingdom – some common features Phylum Class Order Family Genus Species – many common features
What is taxonomy?
This is the study of the classification of organisms
Taxonomists look for common features (homologies) when putting organisms into groups-
What are Phylogenetic trees?
- Modern classification reflects evolutionary relationships.-
- A branch in the tree is when two species started to evolve separately.
- Before the branch the species share a common ancestor.
How are cell walls different in plant, fungi and prokaryotic cells?
Plant cell wall made of cellulose
Fungi Cell wall made of chitin
Prokaryotes no cell wall
What does autotrophic mean?
Organism that can produce its own food
What are the names of the 5 kingdoms of life?
Animalia, plantae, fungi, protoctista and prokaryotic
What were Woese’s new groups?
- bacteria (Eubacteria)
- archaea (Archaebacteria)
What are some features of Bacteria(eubacteria)?
- a different cell membrane
- flagella with a different internal structure
- different enzymes for building RNA
- no proteins bound to their genetic material
- different mechanism for building RNA and replicating DNA
What are some features of Archaea?
- Archaea share some features with eukaryotes:
- similar enzymes for building RNA
- similar mechanisms for building RNA and replication of DNA
- they have proteins bound to DNA
How are eubacteria different from archaea?
- Different cell membrane to archaea
- flagella with a different internal structure to those in archaea
- different enzymes for building RNA
- no proteins bound to their genetic material
- different mechanism for building RNA and replicating DNA.
Why do you think the changes took a long time to be accepted (woese)?
Need to get the agreement of other scientists working in this area.
What are some Classification problems?
DNA analysis often supports traditional Linnaean classification based on homologies.
Sometimes DNA analysis shows that organisms are actually very different.
What is Convergent evolution?
that species evolve to develop similar phenotypic traits.
What is genetic diversity?
When all organisms that reproduce sexually and every individual has a unique combination of alleles,
What is the Importance of genetic variation?
- Genetic diversity allows a population to adapt to changing environments.
- If a population declines some alleles will be lost.
What are some sources of genetic variation?
During meiosis (cell division to make gametes)
-Chromosomes line up randomly - independent assortment.
-Crossing over means that chromosomes swap DNA.
-Random mutations arise that change the DNA base sequence, leading to new alleles.
After meiosis:
-Mate selection determines the possible combinations of alleles.
-Random fertilisation: it is random which sperm and egg and thus which alleles will come together in the offspring. Recessive alleles may be masked.
What are some types of random mutation?
- gene mutation
- chromosome mutation
What is gene mutation?
change in DNA sequence.
What is chromosome mutation?
small sections of chromosomes rearranged during meiosis. Chromosomes can be lost, moved and swapped.
What is a conservation?
The protection of species to reduce the risk of the species becoming extinct
What is species richness?
Species richness is the number of different species in a habitat
What is species eveness?
The numbers of each species in a habitat
What does D stand for in the diversity index equation?
D is the diversity index value
What does N stand for in the diversity index equation?
N is the total number of individuals of all species
What does n stand for in the diversity index equation?
n is the number of individuals of each species
