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Human Biology: Unit 4 > Chapter 10 - Biotechnology Provides Evidence Of Evolution > Flashcards

Chapter 10 - Biotechnology Provides Evidence Of Evolution Flashcards

1
Q

What is Polymerase Chain Reaction? (PCR)

A

A technique used in molecular biology for producing multiple copies of DNA from a sampling.

  • Used in DNA fingerprinting and in identifying diseases.
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2
Q

What is the benefit of Polymerase Chain Reaction?

A

The early limitation of DNA analysis was the amount of DNA needed.
- in many cases there was insufficient DNA or the Organisism may have been adversely affected in order to collect enough…

***The development of PCR has enabled small quantities of DNA to be replicated, producing testable amounts to use in analysis techniques.

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3
Q

Studies in which provide evidence to the theory of evolution:

A

Comparative studies:
Study of fossils
Comparison of Anatomy and Embryology
Comparison of DNA AND PROTEINS

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4
Q

What process does PCR mimic?

What occurs/steps of the process?
explain them

how often is it done?

A

PCR mimics the natural process of DNA replication THAT OCCURS PRIOR to CELL division.

During the process, the DNA goes through a series of 3 steps:

  1. DENATURING: the 2 strands of the DNA are separated
  2. ANNEALING: Short sections of the DNA (PRIMERS) are bound to the separated strands.
  3. EXTENSION: the short sections of DNA are extended to produce longer strands.

THIS PROCESS is REPEATED APPROXIMATELY 20-30 TIMES IN THE PROCESS CALLED THERMOCYCLING.
- 2 to 3 hours to produce a billion copies of the DNA.

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5
Q

What is denaturing?

KEY FEATURES

A

During natural DNA replication, the ENZYME HELICASE SEPARATES THE 2 STRANDS OF DNA, ALLOWING EACH STRAND TO BE COPIED.

The PCR uses HEAT TO ACHIEVE THE SAME FUNCTION.

  • TEMPS APPROX 94-96 DEGREES CELSIUS ARE USED TO BREAK THE HYDROGEN BONDS HOLDING THE 2 STRANDS TOGETHER.

THIS SEPARATES THE STRANDS WITHOUT DISRUPTING EACH INDIVIDUAL STRAND.

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6
Q

What is annealing?

Key features.

A

Temp has decreased to approx 50-60 degrees Celcius

This allows the SHORT STRANDS OF DNA = PRIMER, TO BIND TO THE SINGLE DNA STRANDS

  • THEY ARE NOT RANDOM SECTIONS OF DNA
  • INSTEAD, THEY ARE COMPLEMENTARY TO EITHER END OF THE SECTION OF DNA TO BE COPIED.
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7
Q

What are primers?

A

Short strands of DNA or RNA serves as a starting point for DNA.

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8
Q

What is Extension?

Key features.

A

AKA = ELONGATION
- also mimics the process of DNA replication

The enzyme DNA POLYMERASE is USED TO JOIN NEW, COMPLEMENTARY NUCLEOTIDES TO THE SECTIONS ORIGINATING WITH THE PRIMERS.

  • this EXTENDS, or ELONGATES, the NUCLEOTIDE CHAIN AND CREATES A NEW STRAND OF DNA.

However, it is NOT THE FULL LENGTH of the ORIGINAL DNA, as it STARTS AT THE PRIMER and NOT AT THE END OF THE DNA.

Eventually, the majority of DNA strands are the length of DNA between the location of primers.

DNA POLYMERASE ATTACHES TO DOUBLE-STRANDED DNA.

Prior, to the extension step, THIS ONLY OCCURS WHERE THE PRIMERS ARE LOCATED.
- therefore, the primers act as a starting point, and hence initiate DNA replication.

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9
Q

What do continued rounds of amplification produce?

A

The continued rounds of DNA amplification swiftly produce large numbers of identical fragments.
Each fragment contains the DNA region of interest.

SEE FIGURE 10.2 PG 272

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10
Q

What is TAQ POLYMERASE?
OPTIMAL CONDITIONS?
HOW MADE?
WHEN USED?

WHY IS USED?

A

In the PCR process, the DENATURATION step is CARRIED out at 94-96 degrees celsius.
- At this temp the DNA POLYMERASE IS USUALLY DESTROYED.

This means that MORE OF THE ENZYME HAS TO BE ADDED AFTER THE HEATING STAGE OF EACH CYCLE.
- This is very TIME CONSUMING and USES LARGE AMOUNTS OF DNA POLYMERASE.

Therefore, almost all PCR applications now use a HEAT-STABLE DNA POLYMERASE.

  • Example: THERMUS AQUATICUS OR TAQ POLYMERASE
  • Taken from heat-loving bacteria

It does not nature when heated and has allowed the procedure to be simplified and automated, permitting the PCR sample to be alternatively Heated and cooled.
- Taq polymerase optimal temp = 68-72 degrees c

-EXTENSION PHASE IS CARRIED OUT AT THIS TEMP

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11
Q

What are restriction enzymes?

A

an enzyme that cuts strands of DNA at a specific sequence of nucleotides.

  • ability to cut DNA at a specific sequence of nucleotide
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12
Q

How can restriction enzymes be used?

A

USED
- range of applications, including DNA ANALYSIS
WHEN RESTRICTION ENZYMES ARE ADDED TO DNA, IT CUTS THE STRANDS INTO DIFFERENT LENGTHS DEPENDING ON THE BASE SEQUENCE OF SPECIFIC DNA SAMPLES.

THE LENGTH OF THESE PIECES CAN BE ANALYSED AND COMPARED WITH THEIR DNA SAMPLES.

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13
Q

What gel electrophoresis?

A

A technique that is able to separate DNA STRANDS based on their lengths.

  • used to separate charged molecules based on their size by pushing them through a gel
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14
Q

Steps of Gel electrophoresis

A
  1. DNA pieces are PLACED IN WELLS; an indentation in the gel used for gel electrophoresis
    - In a semi-solid gel (agarose or agar) THAT IS IMMERSED in a solution of electrolyte
  2. There are ELECTRODES at either END OF THE GEL
  3. the NEGATIVE ELECTRODE is CLOSEST to the DNA and the POSITIVE ELECTRODE is at the OPPOSITE SIDE.
  4. The smaller DNA pieces MOVE FASTER than the LARGER ones, AND SO ARE LOCATED FURTHER AWAY FROM THE NEGATIVE ELECTRODE WHEN THE CURRENT IS STOPPED
  5. this RESULTS in a PATTERN of BANDS that LOOK SIMILAR to the BARCODES ON PRODUCTS
  6. This banding pattern is an individual DNA PROFILE OR DNA FINGERPRINT.
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15
Q

What is a DNA PROFILE?

A

DNA FINGERPRINT

  • A technique that uses the banding patterns of DNA fragments as a means of identification;
  • a DNA fingerprint is unique to a particular individual
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16
Q

How to fill the wells?

A

Wells = depressions in the gel
- this means that when the current is applied, the DNA will MOVE THROUGH THE GEL RATHER THAN DIFFUSE THROUGH THE SOLUTION.

therefore, for electro- gelphoresis to work effectively the DNA needs to be accurately placed in the wells.

TYPICALLY DONE BY MICROPIPETTE

  • a fine pipette used to measure and transfer very small volumes of liquid
  • have disposal tips at the end that can be put on and off the pipette without any contact, reducing any chance of cross-contamination
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17
Q

What are DNA ladders?

How is it used?

A

A DNA ladder is often ‘run’ at the same time as the samples.

The ladder contains segments of DNA with Known lengths.

The results from the unknown sample are compared to the ladder to determine the length of the DNA STRANDS in the sample.

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18
Q

After gel electrophoresis how it visualised/
Examples (3)
- what, when, how used?
negatives?

A

After the DNA strands are SEPARATED, scientists use different methods to VISUALISE the DNA.

  1. ETHIDIUM BROMIDE
    - can be added to agar prior to the gel being set
    - as the DNA moves through the gel it PICKS UP some of the chemicals.

Upon completion of the ‘run’, a special ULTRAVIOLET LIGHT is shone over the gel and the DNA FLUORUESCE.

NEGATIVES
- Ethidium bromide is a carcinogen - hence must be handled carefully

  1. Methylene blue
    - is a dye that BINDS To DNA
    - when the gel is SOAKED IN THE DYE, the areas CONTAINING DNA STAIN A DEEPER BLUE and therefore visible to the NAKED EYE.
  2. DNA PROBES
    - short sections of a single strand of DNA with a RADIOACTIVE OR FLUORESCENT MOLECULE that BINDS to the DNA being tested.
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19
Q

What is DNA sequencing?

A

The determination of the precise order of nucleotides in a sample of DNA.

who?

  • frequently used to DETERMINED SUCH A SEQUENCE was invented by Fredrick Sanger
  • awarded his 2nd noble prize in chemistry in 1980
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20
Q

Explain the Structure of DNA…

what happens when DNA FORMS? (2)

A

DNA is synthesised from 4 nucleotides, each with a different nitrogenous base (Adenine, cytosine, guanine, thymine)

  • Nucleotides more correctly called DEOXYNUCLEOTIDE TRIPHOSPHATES; as they consist of 3 phosphates groups to the sugar deoxyribose with its base.

WHEN DNA FORMS

  1. each nucleotide loses 2 phosphates groups
  2. the sugar molecule loses an H atom from the HYDROXYl GROUP (OH) when it BONDS to the phosphate group of an adjacent nucleotide
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21
Q

Explain Sanger’s Method of determining the DNA sequence

A
  1. Synthetic nucleotides that LACK OH group are ADDED TO the GROWING STRAND
    - these are called DIDEOXYRIBONUCLEOTIDE TRISPHOSPHATES or DIDEOXYRIBONUCLEOTIDES (ddNTPs)
  2. The synthetic nucleotide STOPS THE ELONGATION of the sequence because there is no OH. group for the next nucleotide to attach to
  3. This happens at EACH nucleotide in the DNA
  4. Knowing who h BASE was ADDED to CREATE EACH LENGTH ALLOWS SCIENTISTS TO DETERMINE THE ORDER OF NUCLEOTIDES
22
Q

What is Diseoxyribosenucleotide?

A

A modified deoxyribonucleotide that lacks the hydroxyl group of the sugar compotement.

23
Q

When is DNA sequencing used?

A
  1. Identifying MUTATIONS or to COMPARE DNA FROM DIFFERENT ORGANISM
  2. useful in identifying inherited disorders such as SIKELE-CELL ANAEMIA, CF and some form of cancer.
  3. iT HAS ALSO BENN USED FOR MATERNITY AND PATERNITY TESTS
    - in cases, the identity of the father or mother is in dispute
  4. DNA SEQUENCING can be sued by scientists to COMPARE SPECIES IN. ORDER TO TRACK EVOLUTIONARY CHANGES
24
Q

What is the negative to tech advance in genetic engineering

What are the ethical considerations with genetic information? (4)

A

As tech continues to advance, it is BECOMING EASIER and CHEAPER TO OBTAIN INFORMATION
- ethical use of genetic info is an important consideration.

INCLUDING

  1. AUTONOMY - respect for the right to be self-determining and to choose whether or not be tested and, if tested to know and share the information.
    - it also includes the right of an individual to decide their own future, independent of genetic information
  2. CONFIDENTIALITY - the use of genetic info is treated sensitively and is accessed by only those who are authorised to access it
  3. EQUITY - the right to fair and equal treatment regardless of genetic info
  4. PRIVACY - the right to be ‘left alone’ and to make decisions regarding genetic testing and the resulting information, independent of others.
25
Q

What can the information obtained in DNA profiles and sequencing be used for?

A

Comparing the DNA of different organisms

26
Q

‘ALL LIVING THINGS ARE RELATED TO EACH OTHER’.

  • how is this theory supported
  • How are species related/ not
  • explain speciation in this way
A
  • All living things use the SAME DNA CODE
  • adding weight to the hypothesis that ‘ALL LIVING THINGS ARE RELATED TO EACH OTHER’. AND HAVE EVOLVED FROM A COMMON ANCESTOR.

ALL SPECIES of ORGANISMS HAVE DNA
- however, THE SEQUENCE OF BASES OF DNA VARIES

NEW GENES ARE GAINED BY MUTATION
OTHER GENES ARE LOST BY NATURAL SELECTION, GENETIC DRIFT OR SOME OTHER PROCESS.

DESPITE COMMON ANCESTOR - the code in the DNA is different for species.

WHEN NEW SPECIATION OCCURS, the NEW SPECIES WOULD HAVE VERY SIMILAR DNA.
- new species gradually change through mutations, natural selection and genetic drift, new accumulate more and more differences in their DNA.

Species that ARE MORE DISTANTLY RELATED HAVE MORE DIFFERENCES IN THEIR DNA, WHEREAS SPECIES THAT ARE MORE CLOSELY RELATED SHARE A GREATER PORTION OF THEIR DNA.

27
Q

What is a genome?

A

The complete set of DNA in each cell of an organism

28
Q

What is COMPARATIVE GENOMICS?

How does it work?

WHY IS IT USED?

A

COMPARATIVE GENOMICS - is a relatively new field of biological research in which the genome sequences of different species are compared.

  • by comparing the sequence of the human genome with the genome of other organisms, researchers are able to identify regions of similarity and difference.
  • This procedure provides an EFFECTIVE MEANS OF STUDYING EVOLUTIONARY CHANGES AMONG ORGANISIMS,
  • helping to IDENTIFY GENES that are PRESERVED AMONG SPECIES,
  • as well as the GENES THAT GIVE EACH ORGANISIMS ITS UNIQUE CHARACTERISTICS.
29
Q

Human Genome Project
- conclusions

Comparative DNA analysis in play…

A

completed in 2003
- demonstrated that major sequencing projects can generate high-quality data

By analysing the genomic features that have been preserved in a number of species over millions of years, researchers are beginning TEASE APART THE OFTEN-SUBTLE DIFFERENCES BETWEEN ANIMAL SPECIES

  1. COMPARATIVE GENOMICS HAS REVEALED A HIGH LEVEL OF SIMILARITY BETWEEN CLOSELY RELATED ORGANISMS SUCH AS CHIMPANZEES
  2. USED TO REVEAL DIVERSITY OF GENE COMPOSITION IN DIFFERENT EVOLUTIONARY LINEAGES.
    - such research may result in a rearrangement of the way we view some of the evolutionary. relationship between primates
30
Q

Examination of HUMAN GENOME to CLOSEST LIVING RELATIVE

  • Who is it?
  • Relatedness?
  • How different?
A

Examination of HUMAN GENOME to CLOSEST LIVING RELATIVE = CHIMPANZEE

  • they share more than 98% of our DNA
  • scientist quote slightly higher or lower figures depending on exactly what is being compared

HUMANS = 23 PAIRS OF CHROMOSOMES

CHIMPS = 24 PAIRS OF CHROMOSOMES
- hence at some time (theory) 2 small chromosomes found in chimp FUSED TO FORM 1 CHR. in HUMANS

31
Q

What do chromosomes code/ have for?

WHAT ARE NON-CODING SEQUENCES OF BASES?

WHAT HAPPENS WHEN YOU COMPARE THEM WITH OTHERS?

A

Chromosomes contain

  • Genes code for PROTEINS,
  • non-coding sequences of bases

NON-CODING SEQUENCES OF BASES

  • ‘junk’ DNA
  • no apparent function and appear to serve no purpose

COMPARISONS OF JUNK DNA

  • similar result as those for other parts of the genome
  • MORE CLOSELY RELATED SPECIES HAVE MORE JUNK SEQUENCES IN COMMON

THIS OBSERVATION ONLY MAKES SENSE IF RELATED SPECIES HAVE EVOLVED FROM A COMMON ANCESTOR.

32
Q

Example of NON-CODING SEQUENCES OF BASES
(EVR)

HOW MUCH AFFECTED IN DNA?

A

ENDOGENOUS RETROVIRUS

  • stretches of apparently non-functional DNA
  • An EVR IS A VIRAL SEQUENCE THAT VHAS BECOME PART OF AN ORGANISM’S GENOME
  • they STORE THEIR GENETIC INFO, as RNA NOT DNA.
  • 8% of the human genome = has EVR
  • other primates also possess some of the same EVRs in EXACTLY THE SAME LOCATION.
33
Q

Explain how EVR entered the genome?

A
  1. Upon ENTERING A CELL, a RETROVIRUS Copies its RNA GENOME INTO DNA = PROCESS CALLED REVERSE TRANSCRIPTION
  2. The DNA then BECOMES INSERTED INTO ONE OF THE HOST CELL’S CHROMOSOMES.
  3. Retrovirus only BECOMES ENDOGENOUS IF IT INSERTS INTO A CELL WHOSE CHROMOSOMES WILL BE INHERITED BY THE NEXT GENERATION
    - AN OVUM OR SPERM CELL
  4. OFFSPRING of INFECTED INDIVDIUSLA will then HAVE A COPY of the EVR in the SAME PLACE.
    - SAME CHR.
    - IN EVERY SINGLE ONE OF THEIR CELLS
  5. ALL SUBSEQUENT GEN. will also have a COPY OF THEVER AT THE SAME LOCATION.
34
Q

Compare the EVR IN CHIMPS AND HUMANS

  • LOCATION
  • WHY
  • HOW
A 
COMPARING CHR. of HUMANS AND CHIMPANZEES. 
The same EVRs are located
- SHORT ARM OF CHR. 10 
- SHORT ARM OF CHR. 1
- LONGARM OF CHR. 9
- SHORT ARM CHR. 6

Compelling evidence that humans and chimpanzees share a common ancestor

ANY RETROVIRUS THAT HAS BECOME INSERTED INTO THE GENOME OF A COMMO ANCESTOR WOULD BE INHERITED BY BOTH CHIMP AND HUMANS AT THE SAME LOCATION (exactly) in the chromosomes.

35
Q

Define endogenous retrovirus

DEFINE REVERSE TRANSCRIPTION

A

a retrovirus that has become part of an organism’s genome and exists in every cell of the body.

REVERSE TRANSCRIPTION - A PROCESS WHERE THE BASE SEQUENCE IN RNA IS COPIED DURI G THE SYNTHESIS OF DNA.

36
Q

Mitochondria

A

Organelles in the cell where the AEROBIC PHASE OF RESPIRATION OCCURS TO RELEASE ENERGY FOR USE BY THE CELL.

37
Q

Mitochondrial DNA.
Explain its features

vs. nDNA

A
  1. mtDNA
  2. located in Mitochondria
  3. small circular molecules
  4. 5-10 molecules in each mitochondrion
  5. 37 gene; all of which are essential for the mitochondrion to function normally
  6. 24 of these genes code for TRANSFER RNA MOLECULES, which are involved in PROTEIN SYNTHESIS
  7. 13 GENES have INSTRUCTIONS FOR MAKING SOME OF THE ENZYMES NECESSARY FOR THE REACTIONS OF CELLULAR RESPIRATION
  8. MOST CELLS contain LARGE NUMBERS OF MITOCHONDRIA AND THEREFORE USUALLY HAVE BETWEEN 500 ND 1000 COPIES OF THE mtDNA molecule.
  9. This makes it a lot easier to find and extract than the DNA in the NUCELUS, and so smaller samples can be used.
  10. In humans, the mtDNA genome consists of about 16 500 base pairs, representing only a fraction of the total amount of DNA in a cell.

NUCLEAR DNA

  • nucleus
  • long strands
38
Q

How is mDNA inherited?

A

Human eggs and sperm both have mitochondria
egg = many 100s

sperm = only approx 100
- enough to provide the energy for the sperm to swim to the egg

  1. after a sperm has penetrated the egg at fertilisation, the mitochondria in the sperm are rapidly destroyed
  2. nuclear DNA comes from the nucleus of the egg and the sperm, our mitochondrial DNA comes only from the egg.
  3. we inherit Nuclear DNA from both parents, but we inherit mitochondrial DNA only from our mothers
39
Q

Mutations in Mitochondrial DNA

A

Mitochondrial DNA has a HIGHER RATE of MUTATION than NUCLEAR DNA.

  • human mtDNA has BEEN SLOWLY DIVERGING from mtDNA of our ORIGINAL FEMALE ANCESTOR,
  • AMOUNT OF MUTATION IS ROUGHLY PROPORTIONAL TO THE NUMBER OF TIMES THAT HAS PASSED.
40
Q

Use of Mitochondrial DNA in Evolution understanding

-2

A
  1. Scientists are ABLE TO USE SIMILARITY BETWEEN THE mtDNA of ANY 2 INDIVIDUALS TO PROVIDE ESTIMATE OF THE CLOSENESS OF THEIR RELATIONSHIP THROUGH MATERNAL ANCESTOR LIVED LONG AGO.

The use of mtDNA has been found to BE MOST VALUE WHEN COMPARING INDIVIDUALS WITHIN A SPECIES AND FOR SPECIES THAT ARE CLOSELY RELATED.

tracks ANCESTETORY OF MANY SPECIES BACK 100S OF GENERATIONS.

EXAMPLE

  • Trace migration routes of ancient peoples
  • studies have shown most Europeans are DESCENDED from hunter-gatherers who MIGRATED into EUROPE DURING THE LAST AGE.
  • rather than from farmers coming from the middle east east
  1. Used to DEMONSTRATE THE EVOLUTIONARY RELATIONSHIPS BETWEEN SPECIES
    - such analysis, scientists can verify the evidence of evolution gained from other sources

EXAMPLE
- examination of mtDNA has shown that the LAST COMMON ANCESTOR OF MODERN HUMANS AND NEANDERTHALS LIVED APPROX 600000 YRS AGO

41
Q

What are proteins?

how many?

A

Proteins = long chains of particular amino acids linked together in a precise sequence determined by the DNA

  • 10s of 1000s of types of proteins in living things
    FABRICATED FROM 20 KINDS OF AMINO ACIDS.
42
Q

Explain what is Amino Acid or Proetin sequence comparison technique

A
  • provide evidence for evolution

Modern Biochemical techniques enable the sequence of amino acids in a protein to be determined.

by comparing the TYPE AND SEQUENCE of the AA’s in SIMILAR PROTEIN =S FROM DIFFERENT SPECIES - the degree of similarity can be established.

Animals of the same species have identical amino acid sequences in their proteins,
- those from the different species have different amino acids or they are arranged in a different order.

Just like DNA analysis, the DEGREE of DIFFERENCE between proteins ENABLES AN ESTIMATE TO BE MADE OF THE AMOUNT OF EVOLUTION THAT HAS TAKEN PLACE SINCE 2 SPECIES DEVELOPED FROM A COMMON ANCESTOR.

  • LONGER PERIOD OF TIME INVOLVED THE GREATER NUMBER OF AA’s that are different
43
Q

What AA’s Made of?

HOW are AA’s named?

A

AA’s represented by 3 letter code.
- first three letters of their name

To make a comparison of AA chains easier, scientists have also adopted a system of coding whereby 1 letter is used to represent 1 particular AA.

BY listing the AA for a particular protein in sequence, a comparison can be made with other species.

This has been done for a number of proteins that appear to be in all species and which referred to as UBIQUITOUS PROTEINS.

44
Q

What is Cytochrome C?

A

An iron-containing protein that can alternate between a reduced form and an oxidised form;
- important in the electron transport system in cellular respiration

EXAMPLE OF AN UBIQUITOUS PROTEIN
- SHOWS HOW PROTEIN SEQUENCES CAN PROVIDE EVIDENCE FOR EVOLUTION.

45
Q

What is the role of Cytochrome C

A

Protein performs an essential step in the production of cellular energy.

It appears to have changed very little over millions of years of evolution .

Human cytochrome C contains 104 AAs.

Regardless of the species tested, 37 of these have been found at the same positions in every sequenced cytochrome C molecule.

This strongly suggests that these proetisn have descended from an ancestral cytochrome C molecule found in primitive microbe that existed more than 2000 million years ago.

46
Q

What is the role of Cytochrome C

A

Protein performs an essential step in the production of cellular energy.

It appears to have changed very little over millions of years of evolution.

Human cytochrome C contains 104 AAs.

Regardless of the species tested, 37 of these have been found at the same positions in every sequenced cytochrome C molecule.

This strongly suggests that these proteins have descended from an ancestral cytochrome C molecule found in a primitive microbe that existed more than 2000 million years ago.

47
Q

WHAT the main step TO COMPARE C CYTOCHROME SEQUENCES?

How does Cytochrome C link to Common Ancestor?

A
  1. they need to be aligned so that the MAXIMUM No. of POSITIONS CONTAIN ING THE SAME AA can be determined
    - the more similarity there is between the 2 molecules = the more recently they have evolved from a COMMON ANCESTOR.

By doing such comparisons determined that the Cytochrome C of Chimpanzees and Gorilla = same for humans
- Rhesus monkey differs only by 1 amino acid compared that of humans

48
Q

EXAMPLES OF OTHER PROTEIN STUDIES WHICH PROVIDE MORE SUPPORT FOR THE EVOLUTIONARY RELATIONSHIPS BETWEEN PRIMATES THAT HAVE ALREADY BEEN ESTABLISHED IN DNA COMPARISON

  • ALPHA AND BETA
  • DELTA
A

Other protein sequences have been examined and yielded similar results.
- SUCH PROTEIN STUDIES PROVIDE MORE SUPPORT FOR THE EVOLUTIONARY RELATIONSHIPS BETWEEN PRIMATES THAT HAVE ALREADY BEEN ESTABLISHED IN DNA COMPARISON

  1. ALPHA AND BETA
    The alpha and beta chains of the blood protein haemoglobin are identical in humans and chimpanzees,
  • But the same protein sequences in gorillas differ by one AA.
  • When the same chains are examined in Gibbons, there are 3 amino acid differences
  1. DELTA CHAIN
    - A comparison of the delta chain indicates that humans differ from chimps and gorillas by 1 AA, and from gibbons by 2.
49
Q

What is Bioinformatics?

A

Bioinformatics is the use of computers to describe the ‘molecular components of living things.

USES BIOCHEMICAL ANALYSIS TO GAIN INFORMATION ABOUT DNA AND PROTEINS, AND THE COMPUTER SOFTWARE TO STORE AND ANALYSE IT.

  • multidisciplinary field combines all areas of biological science with computer science,e mathematics, engineering and statistics to help understand biological processes.
50
Q

When does bioinformatics become useful?

A

Useful in ASIUSTING EVOLUTIONARY BIOLOGISTS to TRACE THE EVLUTION OF a LARGE NUMBER OF ORGANISMS BY MEARUING THE CHANGES in their DNA
- rather than through traditional techniques of physical taxonomy or physiological observations

THE MORE SIMILAR THE GENES OF 2 SPECIES = THE CLOSER THEIR EVOLUTIONARY RELATIONSHIP

51
Q

What is the process of annotation?

A

Annotation is the identification of genes in a DNA sequence.

52
Q

WHEN DOES ANNOTATION BECOME USEFUL?

HOW USED?

A

This process needs to be computerised, as most genomes are far TOO LARGE to be annotated by hand.

Annotation is made possible by the fact that genes have a recognisable start and stop codons

  • enabled to compare entire genomes
  • genes and other biological features in DNA sequence need to be identified IN A PROCESS CALLED ANNOTATION

Human Biology: Unit 4 (7 decks)

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