Classification and biodiversity Flashcards
1
Q
What is a phylogenetic tree
A
- biological classivication
- reflects evolution of an organism
- places organisms into groups according to visible external features
- show common ancestors
2
Q
What is the hierarchy of classification
A
- smaller groups places into larger ones with no overlap - taxa
- domain , kingdom, phylum, class, order, family, genus ,species
3
Q
What are the three domains
A
- archae - bacteria living in hostile environements - extremophiles - eg extreme temperatures, ph, salinity, pressure
- eubacteria - common bacteria
- euakryotes - plants, animal, fungi, protoctista
- highest category at which organisms are classified
4
Q
What are the five kingdom
A
- based on physical characterisitics
- plantae
- animalia
- fungi
- prokaryotes (bacteria)
- protoctista - many unicellular eukaryotic micro organisms, don’t form tissues - many photosynthesis eg algae
5
Q
What are species
A
- consist of group of similar individuals that can interbreed to form fertile offspring
- large number of physiological and anatomical similarities
6
Q
What is the binomial system
A
- two names
- first name genus capital letter and second species lower case
- universal - able to be used all over world - in latin
- Homo sapien - italics when printed and underlined when written
- H.sapiens
7
Q
What is the tentative nature of classification
A
- infer evolutionary relationship by classifying organisms
- easier manage large number of organims
- new species discovered may not fit into groups currently available
- based on our current knowledge
8
Q
Describe plantae
A
- multicellular eukaryotic organisms that photosynthesis
- autotrophic
- reproduce using spores or seed
- spores - mossed and ferns
- seed - flowering plants
- possess cellulose cell walls
9
Q
Describe animalia
A
- multicellular -heterotrophic
- eukaryotic organisms
- lack cell walls
- have nervous co ordination
10
Q
Decribe fungi
A
- multicellular - moulds
- unicellular - yeasts
- eukaryotic organisms
- moulds - network of threads calle hyphae
- cell wall made of chitin
- heterotrophic by being saprotrophic or parasitic
- reproduce by production of spores (moulds) or by budding (yeast)
11
Q
Describe prokaryotes
A
- microscopic , unicellular oragnisms including bacteria nad cyanobacteria
- cell wall made of peptidocglycan (murein)
- lack membrane bound organelles
- lack true nucleus
- ribosomes are smalleer than eularyotes 70s
12
Q
Describe protoctista
A
- inclue algae and slime moulds
- some unicellular and reemble animal cells (amoeba0
- ohers are colonial and have plant like cells
- contain membrane boudn organelles and a nucleus
13
Q
How do you assess relatedness of organisms
A
- initially performed by looking at physical characteristics from living organisms and fossil evidence
- immunology and recently DNA profiling led to greater understanding of how closley related organisms are
14
Q
What are homologous structures
A
- when comparing features taxonomists look for similar homologous strcutrues
- basic structure is similar but they have different functions
- divergent evolution where sructure has evolved from common ancestor to perform a different function
15
Q
What are analogous structures
A
- same function but different shape/strcutre
- provides evidence of convergent evolution where ancestors adapted to same environmental pressure from different development origins
16
Q
What is immunology
A
- relatedness of species
- comparison of proteins involved in creating antibodies
- one species protein in a rabbit presented to other species proteins
- a proeitn present in all species needs to be identified in order to find organism closest ancestor
- human protein injected into a rabbit to produce antibodies to it
- antibody added to other organisms and degree of prcipitation is measured
- as similarity between protein diminishes lower degree of precipitation
- can be done with haemoglobin
17
Q
What is DNA fingerprinting and sequencing
A
- species evolve changes occur in DNA base sequences more closeluuy related organisms show fewer differences in base sequences
- in eukaryotes majority of DNA does not code for polypeptides thhese non coding regions between genes contain short DNA sequences thaa repeat
- the number of times these repeat is unique dso form basis of genetic fingerprinting
18
Q
What is biodiversity
A
- species richness is a measure of number of different species in a community
- number of organisms within each species represents biodiversity in geographical region
- field has abundance species all with healthy numbers ha a great biodiversity species but with very small numbers
- as you move from poles to equator biodiverity increases due to light inensity increase and water availabolity
19
Q
Would rainforests of deserts have a higher biodiversity and why
A
- deserts with have a lower biodiversity as lack of water so lack of plants
20
Q
What are factors affecting biodiversity
A
- succession - composition of a community changes over time as different species colonise
- natural selection
- human activity - pollution , over fishing, deforestation by physical removal of species or destrcution of havitates, also farming
21
Q
Why are reductions of biodiversity a problem
A
- are a concern many species are staple foods, provide raw materials and where drugs are derived
22
Q
How do you asses biodiversity
A
index of biodiversity measures the number of individuals of each speicies and number of species
23
Q
Describe polymorphic loci and biodiversity
A
- genes position on chromosome referred ass it’s locus
- a locus shows polymorphism if it has two or more alleles that cannot be accounted for mutation alone result in two or more different phenotypes
- porportion of different alleles higher represends a higher biodiversity
24
Q
Why are sampling technique used
A
- estimate number of individuals of species in a given area
- sampling should be random to eliminate bias
25
How do you sample for terrestrial animals
* mark and release and recapture - linccoln index
* animals capured and markes - not harmed of visible to predators
* they're then released
* one animals reintergrate trasps are reset
* total population can be estimated using number of individual in sample 2 and sample 1 that are marked
* you have to assume there are no births/deaths/immigration/emmigration have occurred between collecting samples
26
How do you sample freshwater invertebrates
* collect and identify invertebrates by using quadrat and net in a given area
* kick or rake the area 0.5 m squared for set period
* collect invertebrates downstrream
* release invertebrates carefully
* use simpsons index
27
How do you sample plants
* quadrats and tranects - etimate percentage area cover of different plants with a quarat divinded into long sections
* measure plant dioversity by counting number of plant in a qudrat
* tras=nsact is a length of rope used to measure inervals along an environmental gradient - distance of woodland
28
Explain natural selection
* evolution - new species formed from pre exisiting ones over time
* Darwin observation of variation of a population led to natural selction
* Darwin recognised species changed
* natural selection resultsin species beter adapted to their environment
* organisms overproduce offspring so large varaition of genotypes within a population
* changes in environmental conditions bring new sleection pressure through competition / predetion/disease
* only those individuals with beneficial alleles have selective advantage eg camoflauge
* these individuals reproduce so offspring more likely inherit beneficial allelez
* therefore the beneficial allele frquency increases in gene pool
29
What are the types of adaptation
* anatomical - eg beak shape
* physiological - eg affiniyy got oxygen of haemoglobin
* behavioral - eg noctural animals avoid the heat of the day
30
Domains
* contain organissms that share a distinctive unique pattern of ribosomal RNA which estblishes their close evolutionary relationship
31
Species
* consists of a group of individuals with similar characteristics that can interbreed and produce fertile offspring
32
Autotrophic nutrition
* is making comlex organic molecules from simple inorganic ones using either light or chemical energy
33
Heterotrophic nutrition
* invollves consumption of already made complex organic molecules
34
Saprophytic nutrition
* involves feeding on dead or decaying matter by the production of enzymes extracellularly and the subsequent absorption of the products
35
Parasitic nutrition
* ivolves obtaining nutrients from a host organisms over a long period of time causing it harm in the process
36
Homologous
* structures in different species with similar anatomical position and developmental origin derived from a common ancestor
37
Analogous structures
* have a corresponding function and similar shape but have a different developmental origin
38
Biodiversity
* the number of species and the number of individuals of each species in a specifies geographic region
39
Gene
* is a section of DNA on a chromosome that codes for a particular polypeptide
40
Allele
* different form of the same gene
41
Phenotype
what an organism looks like its characteristics
42
Gene pool
total number of allles within a population
