4.5 Species and taxonomy Flashcards
(107 cards)
1
Q
Define species
A
- Organisms with shared characteristics that can interbreed to produce fertile offspring
2
Q
Why doesn’t the definition of a species work
A
- Doesn’t fit for single-celled organisms since they don’t interbreed
- There’s a lot of variation between individuals in a species (e.g. in dogs)
3
Q
Even where groups of extinct organisms have left fossils records, it is very difficult to distinguish different species. Suggest 2 reasons why
A
- Can’t interbreed fossils to see whether they produce fertile offspring
- Not all characteristics can be observed
- Fossil records are pretty incomplete
4
Q
What is the behaviour of members of the same species like
A
It’s more alike than that of members of different species
4
Q
Suggest why it’s often difficult to classify organisms as distinct species
A
Variation within a species is very large
5
Q
How does organisms of the same species acting in a similar way beneficial to the organisms
A
Individuals can recognise member of the same species by the way they act
6
Q
How is the ability to display behave determined
A
Genetically determined
7
Q
What 5 things do courtship behaviours do that enables successful mating and that the offspring have the max chance of survival
A
- Recognise member of their own species
- Identify a mate that is capable of breeding
- Form a pair bond
- Synchronise mating
- Become able to breed
8
Q
Why does the fact that courtship behaviours help individuals recognise member of their own species , ensure that mating is successful
A
It ensures that mating only takes place between members of the same species because only members of the same species can produce fertile offspring
9
Q
Why does courtship behaviours enabling identification of a mate that is capable of breeding beneficial
A
Since both partners need to be sexually mature, fertile and receptive to mating
10
Q
Why does courtship behaviours forming a pair bond beneficial
A
Since this bond will lead to successful mating and raising of an offspring
11
Q
Why does courtship behaviour enabling synchronised mating beneficial
A
It takes place when there is the maximum probability of the sperm and egg meeting
12
Q
Why does courtship behaviours enabling individuals become able to breed beneficial
A
By bringing members of the opposite sex into a physiological state that allows breeding to occur
13
Q
What is courtship behaviours in humans
A
Foreplay
14
Q
Explain how courtship behaviours enables successful mating
A
- identify their own species
- Synchronises mating and therefore increased the chance of offspring reaching reproductive age
- Female being receptive
- Creating a pair bond which increase the chance of fertile offspring and raising offspring
15
Q
What are the 2 reasons why taxonomy is needed
A
- Predict characteristics
- Evolutionary relationships
16
Q
What is the term of biological classification
A
Taxonomy
17
Q
What are the 3 categories the 5 kingdom classification create
A
- Cell type
- Organisation of cells
- Nutrition
18
Q
What is the order of the hierarchical system
A
- Kingdom
- Phylem
- Class
- Order
- Family
- Genus
- Species
19
Q
What is meant when saying the hierarchical system groups are discrete
A
The groups don’t overlap
20
Q
In the hierarchical system are the smaller groups have more in common or the larger groups
A
The smaller groups
21
Q
What’s the kingdom of humans
A
Animals
22
Q
What is the phylem of humans
A
Chordates
23
Q
What is the class of animals
A
Mammals
24
What is the order of humans
Primates
25
What is the family of humans
Homonids
26
What is the genus of humans
Homo
27
What is the species of humans
Sapien
28
In the binomial naming system what 2 categories are used
Genus followed by the species
29
What language is the binomial system in
Latin
30
What is implied when the first word of the binomial system but the 2nd word is different for 2 organisms
The genus is the same but the species is different which implies evolution relationships
31
When writing the binomial system names, where is the capital letter and where is the lower case, write the human one
Capital letter of genus
Lower case of species
Homo sapien
32
What must you do when writing binomial system names
Underline when written by hand
33
What do phylogenetic trees show
Shows the evolutionary relationships
34
In a phylogenetic tree, what is the name of when the 2 lines split
- Points of divergence
- Common ancestors
35
What is the name of the line from the original ancestor to the end of the branch in a phylogenetic tree
Line of descent
36
What are homologous structures
Features with the same fundamental structure but different function
37
Homologous structures show what type of evolution
Divergent evolution
38
Name an example of homologous structures
Pentadactyl limbs
39
What are analogous structures
Different fundamental structures but same function
40
Analogous structures show what type of evolution
Convergent evolution
41
Are homologous structures or analogous structures used to provide evidence of common ancestors
Homologous structures
42
What is convergent evolution
When different organisms with not necessarily common ancestors come together at the same place
43
What is an extremophile
Organisms that can live in extreme environmentally conditions
44
How are domains separated
Different rRNA base sequence
45
Are eubacteria, archaea or eukaryota extremophiles
Archaea
46
Where does domain come in the hierarchical system
Before kingdom
47
What is genetic fingerprinting
The examination of VNTRS
48
What does VNTR stand for
Variable number tandem repeats
49
Where do you find VNTR
In the introns of human DNA
50
Roughly what % of DNA is introns
About 95%
51
What are introns
Non coding region of DNA
52
What is the probabiltity like of 2 individuals having the same VNTRs
Very low
53
When you're closely related to someone, what are your VNTRs like
Get more similiar the more closley related you are
54
What does the analysis of VNTRs DNA fragments determine
The genetic relationships and the genetic variability within a population
55
What are the names of the 7 steps in order of genetic fingerprinting
- Collection
- Extraction
- Digestion
- Separation
- Hybridisation
- Development
- Analysis
56
Name 3 places where you might be able to collect the DNA sample for genetic fingerprinting
- Blood
- Body cells
- Hair follicles
57
What happens when the DNA you are sampling for genetic fingerprinting is very small
The DNA is cloned via PCR which is used to amplify the amount of DNA
58
Why do we need digestion when doing genetic fingerprinting
To cut the large sample up into all the different VNTRS within the organisms/ human
59
What is the name of the enzyme that digest/ cut the DNA during genetic fingerprinting into smaller fragments
Restriction endonucleases
60
When selecting the restriction endonucleases, what must their active site be complementary to in order to digest in the genetic fingerprinting
Complementary in shape to the sequence just before the VNTRS
61
Why must the restriction endonucleases active be complementary in shape to the sequence just before the VNTRS when doing genetic fingerprinting
So the enzyme cuts the DNA just before and just after the VNTRS so the entire length of the VNTRS is maintained
62
Why do we need to separate out the VNTRS
So we can analyses which VNTRs the individual has
63
During the separation process of genetic fingerprinting, where are the DNA samples loaded into to in the agar gel
Into small wells
64
During the separation process of genetic fingerprinting, what type of liquid is poured over the top of the gel
A buffer liquid
65
During the separation process in genetic fingerprinting, what is applied to the agar gel that has a buffer liquid on top
An electrical voltage
66
What end of the gel has a negative charge in genetic fingerprinting
The end closest to the DNA
67
What end of the gel has a positive charge in genetic fingerprinting
The end furthest away from the DNA
68
Is DNA positively or negatively charged
Negatively charged
69
Why does DNA being negatively charged help to move the DNA down the agar gel in genetic fingerprinting
Since the end furthest away from the DNA in the wells is positively charged and opposite charges attract
70
What group in DNA makes DNA negatively charged
The phosphate group
71
What is the name of the stage when the electrical voltage is added to the agar gel inn genetic fingerprinting
Gel electrophoresis
72
What does the agar gel create when the DNA moves from the agar well towards the positive end of the gel in genetic fingerprinting
The agar gel creates resistance
73
Do the smaller or larger pieces of DNA travel faster and further along the gel during gel electrophoresis, when the agar gel is creating resistance
The smaller pieces of DNA / The smaller length VNTRS
74
What does the different distance travelled through the agar gel during gel electrophoresis do
It separates the different lengths of DNA VNTRS
75
What is added to the agar gel after the VNTRS have been separated during gel electrophoresis
An alkaline
76
Why is an alkaline added to the agar gel after the separation of VNTRS during gel electrophoresis
To separate the double strands of DNA into single strands
77
What is hybridisation
Adding a different piece of DNA to the DNA that is in the agar gel - so you are left with a hybrid piece of DNA
78
What is the name of the DNA that is added to the single stranded DNA in the agar gel
DNA probes
79
What is a DNA probe
Short, single stranded pieces of DNA complementary in base sequence to the VNTRS and they are always labelled
80
What are the 2 usual things that a DNA is labelled with
- Radioactive chemical
- Fluroescent chemical
81
Are the DNA probes that are added to the single stranded DNA in the agar gel different or the same
DIfferent DNA probes
82
After adding the DNA probes to the agar gel, what happens
We wash the gel to remove any unbinded DNA probes
83
What is meant by the development stage in genetic fingerprinting
How we visualise the position of the VNTRS
84
In the development stage in genetic fingerprinting, what are the hybrid DNA transferred on to
A nylon sheet
85
Why are the hybrid DNA transferred onto a nylon sheet in the development stage of genetic fingerprinting
Since when the agar gel is taken out of the buffer liquid the gel will shrink and crack as it dries which wouldn't produce a clear image so tranfer onto the nylon sheet so the DNA lasts longer
86
What determines which development method is used to develop the image from the nylon sheet
The label on the DNA probe
87
If the DNA probe was labelled using a radioactive label how is the nylon sheet developed
Expose the sheet to x-rays
88
If the DNA probe was labelled using a fluorescent label how is the nylon sheet developed
Expose the sheet to UV light
89
When the nylon sheet is exposed to x-ray what colour are the bands
Black and white
90
When the nylon sheet is exposed to UV light what colour do the DNA probes attached to the VNTRS glow
A greeny / yellow colour
91
When analysing the developed hybrid DNA, what is always put into the picture
A marker
92
What is the marker in the analysis of VNTRS
A DNA sample with VNTRS of known lengths is put into the first well
93
When analysing the genetic fingerprinting, what are you commparing
The position of the DNA bands
94
How does genetic fingerprinting help in paternity tests
- The child's DNA will contain VNTRS from the mother and some from the father
- Line up the mothers's and child's
- So any band in the child that doesn't match up with the mother must have come from the father
- So the father can be identified
95
What are 3 uses of genetic finger printing
- Medical diagnosis
- Forensic science to place suspects at crime scenes / paternity tests
- To ensure animals and plants are not closely related before being breed
96
How does genetic finger printing help with medical diagnosis
- Examine someones DNA
- And see if they have VNTRS in the positions which are expected or known to be in those positions of individuals who suffer from a particular genetic diesease
97
How does genetic fingerprinting ensure that animals and plants are not closely related before breeding
- Take 2 organisms that you want to breed
- Examine their genetic fingerprint
- And make sure their VNTRS are not too similar
98
Why do people need to check the genetic finger print of 2 organisms to ensure they aren't too closely related before breeding
It reduces the risk of passing on genetic conditions / harmful genetic conditions
99
What are the 6 pieces of evidence that shows shared ancestry for all life
- All have DNA or RNA as their genetic material
- The genetic code is universal - same codon on mRNA for an amino acid
- The proteins in all organisms are formed from the same 20 amino acids
- ATP is the universal molecule for energy
- All have phospholipid membranes
- Vital physiological processes follow very similar metabolic pathways in all organisms
100
What 3 comparisons of genetic diversity can be used to classify organisms
- Base sequence of DNA
- Base sequence of mRNA
- Amino acid sequence
101
Other than hunting, suggest 2 reasons why populations might show very low levels of genetic diversity
- Populations might have been very small / genetic bottleneck
- Populations might have started with small number of individuals
- Interbreeding
102
What is meant by genetic diversity
Number of different alleles of each gene
103
Give 2 ways the student would have ensured their index of diversity was representative of each habitat (2 marks)
1. Random samples;
2. Large number (of samples)
OR
(Continue sampling) until stable running mean;
104
State 3 comparisons of genetic diversity that can be used to class organisms (3 marks)
- Base sequence of DNA
- Base sequence of mRNA
- Amino acid sequence of proteins
105
Describe how breeding experiments could determine whether the 2 populations are from the same species (2 marks)
- Breed the 2 organisms together
- Same species produce fertile offspring
106
Other than hunting, suggest 2 reasons why populations might show very low levels of genetic diversity (2 marks)
- Population might have been very small/ genetic bottleneck
- Population might have started with small number of individuals/ by one pregnant female/ founder effect
- Inbreeding
