Classification Flashcards
Define biodiversity
Measure of vareity of living organism and their genetic difference
Define evolution
The process by which natural selection acts on variation to bring about adaptions and eventually speciation
What is Morphology
The study of form and structure of organism
Define Analogous feature and give examples
Features that look similar or have similar function but arent from the same biological orgin
EX. The wingsupper in different animals has similar function but different structure
Deinge homologous structure and give example
Structure that genuinely show common ancestry
EX. Pendactyl limbs appear in different animals and is simlar in structure & location but doesnt show the same function
List the taxomic groups from largest to smallest
Domain,Kingdom, phylum,class, order,family,genus and specie
Mnemonic
Dumb king play chess on fancy good squares
How many domains are there and what are they
Archea
Eubacteria
Eukaryota
Archaea contains how many kingdom
1 kingdom
Auchaebacteria
Bacteria contains how many kingdom
1 kingdom
Eubacteria
Eukaryota contain how many kingdoms
4 kingdoms
Protista
Fungi
Animalia
Plantae
What are plantae
Multicellular Autotrophs
Make their own food by capturing light (photosynthesis) by chrophyll
EX. Mosses,ferns, angiosperm
What are fungi
Heterotrophs
Most are saprophytic ( live off dead organism using extracellur digestion) chitin cell wall
Reproduce by spores
Some are parasitic
What are animalia
Heterotrophs(eat others for food)
Capable of whole body movement
No cell wall
Reproduce sexual but sometimes asexually
EX invertebrates (insects and mollusc) and vertebrates (fish amphibians,reptiles and birds)
What are protista
Have features of other kingdoms
Diverse group of microscopic organism
Mainly reproduce asexually
Reason for classification
Identify species
Predict characteristicsx
Find evlutionary links
Why do specie look similar
- live in similar environment
- have similar selection pressure
- similar allele will have the selective advantage
- produce similarbsame proteins & therefore have similar characteristics
Classification system
Understand relationship between organism & keep track of changes
- system used needs to be universal
- system is based on putting organism into groups
Ways to classifly
Dna sequence
mRNA sequence
Amino acid sequence
Immological -comapre sinialry in self antibody shape
Binomial system must contains
Every organism is given two latin names
- genus
- specie
Binomial system rules
- the genus name has an upper case first letter
- specie name has a lower case first letter
- italic should always be used unless handwritten when they should be underlined
- after the first use the binomial names are abbreviated to the initial of the genus and the species names
Define specie
A group of organism with similar characteristics that interbreed to produce fertile offspring
Define sexual dimorphism
Describe specie where there is a great deal of difference between the appearance of the male and female
Limitation of specie
Sometime population are geophically separated and cannot interbreed but they are the same species
Sometimes separate species can mate to produce fertile offspring
Plants often interbreed with different species to produce fertile hybrids
Many organism dont reproduce sexually
Fossil organism dont reproduce
Define molecular phylogeny
The analysis of the genetic material of organism to establish their evoluntionary relationships
What are the three different ways molecular phylogeny ways
Ecological specie model
Mate recognition specie model
Genetic specie model
What is ecological specie model
And advantages
Based on the ecological niche occupied by an organism
Easy to see and measure differences
Ecological specie disadvantages/limitation
-visible difference dont always indicate different species
—> lack of visible difference doesnt mean they are the same species
- not robust way of identifying species
- definition vary
What is a mate recognition specie model and what are the advanatges
Based on unique fertilisation system
Succuesful breeding with a fertile offspring is unequivocal in animals if it occurs
Mate recognition specie model disadvantages
- can be very difficulg to set evidence
- particualry in slow breeding organism and those that live in different localities
- different species of plants often cross breed and produce fertile offspring
What is a genetic specie model and advantages
Based in DNA evidence
Gives unequivocal evidence of organism in same specie and of the relationship between species
Genetic specie model disadvantages
Expensive
Needs high tech equipment
Generates large amount of data
What is DNA sequencing
A specie model by which is base sequence of all or part of a genome of an organism is worked out
DNA sequencing is used
Can tell you the DNA profile of an organism and organism of the same species will have certain proportion of the same DNA
It can be used to see the evolutionary relationship between organism (phylogeny)
what is bioinformatics
Since DNA sequencing and profiling generates lots of data . Bioinformatics is used to organise and analyse enormous amount of raw biological data
Why is it so important to be able to identify individual species
To measure genetic diversity, to identify relationships between different species, to track the process of evolution, to monitor effects of human activities, etc.
What is gel electrophoresis
A method of separating fragments of proteins or nucleic acid based on their electrical charge and size
How does gel electrophoresis work
1) sample added to wells on an agarose gel plate along with some known samples to compare to
2) samples have been treated with restriction endonucleuses which cut the DNA at specific points making smaller fragments
3) the gel contains gye that binds to these fragements and will flouresce undeer UV light
4) then electric current is passed through the gel. The fragment move at different rates through the gel, depending on their mass and charge from the negative cathode to positive anode
5) UV light is shone on it show up the pattern
What are blood pigment used for
Blood pigment are important in many animal group
Analysis show that any group contain only one type of blood pigment
What are analysis of sequence of amino acid
Analysis of the sequence of amino acid in some specific proteins can help show the relationship within high groups such as phylum
What is a phylogenetic tree
Model used to show the relationship between different groups of organism
Archabacteria : prokarotic cell
Ancient bacteria include extromephiles bacteria that can survive extreme conditions of heat and cold, pH, salinty and pressure
Reproduce asexually
What is eubacteria
True bacteria and cyanobacteria which is used to be called the blue green algae
Reproduce asexually
EVALUATION OF SCEINTIFIC COMMUNITY
1) all scientist publish full details of their investigation in well known scientific journals. Their reports must contain full details of their methodology
Original data
Analysis of their fings
Following some strict rules
What is peer review
Other scientist check details of the method
The data collected
And the validity of conclusion before approving its publication
Evaluation of conferences
Universities and other institution often host meetings of scientist from aorund the world specialising in one particular area of research
- allow individual to share ideas, discuss common problems
Argue their case where different models are proposed
Evaluation of wvidence fro other scientist
the evidence will help to support the suggestion, to reject the suggestion, or lead to a modification of suggestion
Specie non fertile
Example
Horse and donkeys
—> mule (sterile)
The gene cant flow to the next generation because not from the same species
Specie fertile
Largest horse + smallest pony
(Extreme variant of the sme species)
Foals
Lions + tiger (different species)
—> most offspring fertile
How does the gel electrophoresis occur
-Of the electrical charge molecules carry – positively charged molecules will move towards the cathode (negative pole) whereas negatively charged molecules will move towards the anode (positive pole) eg. DNA is negatively charged due to the phosphate groups and thus when placed in an electric field the molecules move towards the anode
Different sized molecules move through the gel (agarose for DNA and polyacrylamide – PAG for proteins) at different rates. The tiny pores in the gel result in smaller molecules moving quickly, whereas larger molecules move slowly
-Of the type of gel – different gels have different sized pores which affects the speed the molecules can move through them
DNA separation
DNA can be collected from almost anywhere on the body, e.g. the root of a hair or saliva from a cup. After collection DNA must be prepared for gel electrophoresis so that the DNA can be sequenced or analysed for genetic profiling (fingerprinting)
To prepare the fragments scientists must first increase (amplify) the number of DNA molecules by the polymerase chain reaction (PCR). Then restriction endonucleases (enzymes) are used to cut the DNA into fragments
Different restriction enzymes cut the DNA at different base sequences. Therefore scientists use enzymes that will cut close to the variable number tandem repeat (VNTR) regions
Variable number tandem repeats (VNTRs) are regions found in the non-coding part of DNA. They contain variable numbers of repeated DNA sequences and are known to vary between different people (except for identical twins). These VNTR may be referred to as ‘satellite’ or ‘microsatellite’ DNA
To separate the DNA fragments in gel electrophoresis the scientists
Create an agarose gel plate in a tank. Wells (a series of groves) are cut into the gel at one end
Submerge the gel in an electrolyte solution (a salt solution that conducts electricity) in the tank
Load (insert) the fragments into the wells using a micropipette
Apply an electrical current to the tank. The negative electrode must be connected to the end of the plate with the wells as the DNA fragments will then move towards the anode (positive pole) due to the attraction between the negatively charged phosphates of DNA and the anode
The smaller mass / shorter pieces of DNA fragments will move faster and further from the wells than the larger fragments
The fragments are not visible so must be transferred onto absorbent paper or nitrocellulose which is then heated to separate the two DNA strands. Probes are then added, after which an X-ray image is taken or UV-light is shone onto the paper producing a pattern of bands which is generally compared to a control fragment of DNA
Probes are single-stranded DNA sequences that are complementary to the VNTR regions sought by the scientists. The probes also contain a means by which to be identified. This can either be:
radioactive label (eg. a phosphorus isotope) which causes the probes to emit radiation that makes the X-ray film go dark, creating a pattern of dark bands A fluorescent stain / dye (eg. ethidium bromide) which fluoresces (shines) when exposed to ultraviolet (UV) light, creating a pattern of coloured bands
Heterotrophic cells:
To overcome a small SA:V ratio ancestral prokaryote cells developed folds in their membrane. From these infoldings organelles such as the nucleus and rough endoplasmic reticulum formed
A larger anaerobically respiring prokaryote engulfed a smaller aerobically respiring prokaryote (which is not digested)
This gave the larger prokaryote a competitive advantage as it had a ready supply of ATP and gradually the cell evolved into the heterotrophic eukaryotes with mitochondria that are present today
Autotrophic cells:
At some stage in their evolution, the heterotrophic eukaryotic cell engulfed a smaller photosynthetic prokaryote. This cell provided a competitive advantage as it supplied the heterotropic cell with an alternative source of energy, carbohydrates
Over time the photosynthetic prokaryote evolved into chloroplasts and the heterotrophic cells into autotrophic eukaryotic cells
Evidence to support endosymbiotic theory
Both reproduce by binary fission
Both contain their own circular, non-membrane bound DNA
They both transcribe mRNA from their DNA
They both have 70S ribosomes to synthesise their own proteins
They both have double membranes
How eukaryotic cells may have develop by engulfing prokaryotes into mitochondria
1) cells respire anarobically (they didnt use O2 + didnt have mitochondria)
2) cell engulfs aerobic prokaryotes as food —> ATp is released
3) oxygen levels in atmosphere increases as photosynthetic prokartows appear . Oxygen is at best no use to cells, at worst toxic
4) by chance in some cells the aerobic prokaryotes is not digested, it uses oxygen for cellular respiration. More efficeint respiration allows cells to grow and reproduce more rapidly
5) aerobic bacterium evolved into a mitochopndria ( copies are made and passed to daughter cells during reproduction
How eukaryotic cells may have develop by engulfing prokaryotes into chloroplast
1) cell engulf photosynthetic (heterotrophic) organism as food
2) by chance in some cells the photosynthetic organism is not digested
Photosynthesis continues providing the cell with food this gives the cell an advanatge as it can grow and reproduce more rapidly
4) photosynthetic bacterium evolved into a chloroplast
How to use a quadrant
1) place randomly (using a random number generator)
2) coount the number of individual of a particular species
3) repeat +place many more quandrants
What is morphological specie model
A species definition based solely on the appearance of the organism observed
Describe how scientist use this specie concept in classification
Based on appearance of the organism. Organism with similar appearance are put in the same group
Ex all cats look similar but know regardless domestic cats are not the same specie as tigers although they are related
Protoctista
Eukaryotic
Single called
Free living
Live in water
Fungi
Eukaryotic
Mycelium consist hyphae
Chitin cell wall
Multi nucleate cytoplasm
Free living
Saprptrophic / heterotrophs
Spore reproduction
Plantae
Eukaryotic
Multicellular
Autotrophic
Cellulose cell wall
Photosynthesis
- chlorophyll
Animalia
Eukaryotic
Multicellular
Able to move
Heterotrophs
Fertilised eggs developed to blastocyst
Suggest how worse idea was critically evaluated
Scientific finding ( in a journal)
Scientific conference
Peer review
Repeat experiment to confirm
