topic 4 - genetic infomration, variatoin and relationships between organisms

Question 1

why do different specieslook the same?

Answer 1

similar environmnents
similar selction pressures
similar alles with selctive advantage
similar protiens produced
similar charachteristcs

Question 2

3 domains

Answer 2

eukaryotes
prokaryotes
archea

Question 3

why do we clasify organisms?

Answer 3

understand relationships between organisms
universal
treack changeswhy

Question 4

why do we not clasify off the basis of physical characteristcis?

Answer 4

some members of the same specifies look different e..g idfferent dog breeds
some different species look similar, may accidently class htem as the same speciies.

Question 5

phylogenic clasifcation

Answer 5

tells us about evolutionamlry origins and relsationships
who and how closely related

Question 6

what do we classify on the basis of?

Answer 6

mrna sequence
dna seqeunce
amino acid sequence
immunological - shape of self anti bodies

Question 7

what are the taxes

Answer 7

domian
kingdom
phylum
class
order
family
genus
species

Question 8

hierarchy defenition

Answer 8

smaller groups within larger groups, no overlap between groups.

Question 9

binomial name.
what is it ?
why do we use it?

Answer 9

genus. species
universal and gives us a better understnaidn gof how species are related

Question 10

what are some of the ways bioldiversity is decreased?

Answer 10

destriction of hegerows
selective breeding
monocultures
draining weltsnds
over grazing
fillings ponds

Question 11

what is genetic diversity?

Answer 11

variety of genes within all indivuduals of a population of one species

Question 12

ecosystem diversity

Answer 12

range of different habitats

Question 13

species richness

Answer 13

number of species in a particilar area at a parcticluar time

Question 14

species diversity

Answer 14

number of soecies and indivudlas within each species in a comunity

Question 15

what is an index of diversity?

Answer 15

measure of soecies diversity measures the relationship between the number ofspecies in a comunity and numbr of indiviuduals in a species.

Question 16

what are mutations

Answer 16

alteratoin of base dna

Question 17

what are the mutagenic agents

Answer 17

alpha or beta
x rays or gamma rays
carcinogens

Question 18

outline additoin ( mutatoin )

Answer 18

nucleotide is added in
frame shift altering amino acid sequence
akk triplets byone mutation are altred

Question 19

outline deletion ( mutation )

Answer 19

backwards frame shift

Question 20

outline substitution ( mutation )

Answer 20

one base is swapped for another
degenrate - possibly no change

Question 21

outline inversion ( mutatin )

Answer 21

selection of bases leave and return inversted

Question 22

outline transolcation ( mutatin )

Answer 22

leave and attatch onto different chromozones

Question 23

what is directional selection

Answer 23

extreme trait has sleective advantage due to a chnage in the envoronment

Question 24

3 different adaptation types

Answer 24

anatomical
physical
behavioural

Question 25

evolution - defentiotn

Answer 25

change in allele freuencey over many generations in a population

Question 26

how to identiify meiosis

Answer 26

2n - n diploid - haplopid

Question 27

4 steps to crossing over:

Answer 27

when facing eachoher parts of chormatids become twisted around eachother this puts tention on the pars of chromatids causing them to break broken portions of chromatids rejoin wiht another chormatid new allele combos

Question 28

oitline indepandant segregatoin

Answer 28

randomly paternal and paternal pairs line up on the qeuator of the cell pairs are seperated and one of each pair ends up in the daughter cell

Question 29

how is variatoin is mitosis produced?

Answer 29

crossing over independatn segrgation

Question 30

what is 2n

Answer 30

number of homogenous pairs indenedant segregatoin

Question 31

random fertlaisatoin...

Answer 31

produced vsristion in chromozones (2^n)^n

Question 32

what are three main features of the genetic code

Answer 32

universal degenrate non overlapping

Question 33

what are start codons

Answer 33

start of the polype[tide chain

Question 34

what are stop condons

Answer 34

end of the polypeptide chain dont code for amino acids ( so no completmeentry anti codons ) atc, act, att caude ribsolsome to detatch and stop translocatoin

Question 35

what is degenerate. advantage why?

Answer 35

each amino acid is coded for by mroe than one triplet of bases point mutatoin - change in one base trieplet dsifference, may still code for the same aa ( silent mutastion )

Question 36

what is universal. advanatge?

Answer 36

same base triplety codes for the same amino acid ine every organism adv - genertic engenering is possible e.g inserting human gene for insulin into basvteria

Question 37

what is non overlapping. advantage?

Answer 37

each base is only part of one trplet, triplets read as one discrete unit advantage? - point muation only affects one codon / triplet - 1 aa

Question 38

what are introns

Answer 38

non conding section of dna not in bacteria spliced out of mrna

Question 39

what are exons

Answer 39

coding section of dna code for animo acid therefore polypetide chain

Question 40

what is genome

Answer 40

compete set of dna

Question 41

what is a proteome

Answer 41

range of protiens that is constantly changing

Question 42

what are homologous pairs of chromozones

Answer 42

same genes different allels

Question 43

dna is wrapped around? to creat?

Answer 43

histomes, neucleozomes ( only in eukaeyontes )

Question 44

what is a gene

Answer 44

seoction of dna conding for a polypeptide and functional rna

Question 45

what is a locus

Answer 45

location of a particalr gene on a chromozone

Question 46

alle what is

Answer 46

a version of a gene

Question 47

transciption - defenition

Answer 47

copy of one gene onto mrna

Question 48

translation - defenition

Answer 48

mrna joins with ribosome and trna beings specific amino acid

Question 49

steps - transciption

Answer 49

1. dna helix unwinds 2. one strand used as a template 3. done by dna helicasse catalisng the reaction breaking hydrogen bonds 4. free mrna neucleotides join wiht template strand 5. rna polymerase bings erna neucolotides

Question 50

what happens after transcription

Answer 50

pre mrna is made into mrna introns spliced out vias splicezome

Question 51

steps to translatoin

Answer 51

mrna attatvhed to ribosome in cytoplasm at start codon trna wirth completmentry anti codons aligns oposite mrna polymerase contunies till stop codon ( doesnt code for mrna ) so ribosome detatches