4.1.3 classification and evolution Flashcards

Question

what makes the domains different

Answer 1

they contain a unique form of rRNA and different ribosomes eukarya: 80s ribos, RNA polymerase has 12 proteins archae: 70s ribos, RNA polymerase has 8-10 proteins bacteria: 70s ribos, RNA polymerase has 5 proteins

Answer 2

By comparing similarities in the DNA and proteins of species, we can discover evolutionary relationships. For example Hb in humans and chimpanzees is different in one amino acid, and 3 between humans and gorillas, as the structure is remarkably similar, it is an indication of common ancestry between primate groups.

Answer 3

groups organisms using differences in sequences of nucleotides in the cell’s ribosomal RNA, and the cells’ membrane lipid structure and the sensitivity to antibiotics. Woese’s system divides prokaryotae into eubacteria and archaebacteria . Although they are both unicellular prokaryotes, their chemical composition is different, for example eubacteria have a peptidoglycan cell wall and archaebacteria don’t.

Answer 4

if they belong to similar ecological niches and experiecne the same environmental pressure resulting in natural selection of similar characteristics.

Answer 5

classifies organisms according to their evolutionary relationships, not visible differences. species that share a more recent common ancestor are classified together.

Answer 6

produces a continuous tree compared to discrete groups in taxonomy- scientists not forced to put organisms in a group that doesn't quite fit.

Answer 7

certain large biochemical molecules that are found in all living things perform the same function but they vary slightly. differences reflect the evolutionary history of the species. these include cytochrome C and DNA

Answer 8

its a protein used in respiration, can have different amino acid sequences, and shows evolutionary relationships between species. for example we have the same sequence as chimps, but 1 amino acid different from rhesus monkeys, whilst dogfish are 11 amino acids different.

Answer 9

the percentage difference in coding DNA can be used to determine evolutionary history.

Answer 10

the theory that describes the way in which organisms evolve, or change, over many years as a result of natural selection.

Answer 11

Darwin noticed that organisms which are best suited to their environment are more likely to survive and reproduce, passing on their characteristics to their offspring. gradually, a species changes over time to have a more advantageous phenotype for its environment.

Answer 12

fossils are formed when organisms' remains are preserved in rocks. over time, sediment is deposited on the earth to form strata. the fossil record shows that - fossils of simplest organisms like bacteria and algae and found in the oldest rocks, fossils of more complex organisms are in more recent rocks, supports theory that simple life forms have evolved into more complex ones - the sequence in which the organisms are found matches their ecological links - by studying similarities in anatomies of fossils, we can see how closely related organisms have evolved from the same ancestor - fossila allow relationships between extinct and current organisms to be established the fossil record is incomplete, many organisms are sot bodied and decompose too quickly to fossilise.

Answer 13

the study of differences between living species. a homologous structure is a structure that appears superficially different in different organisms but has the same underlying structure. e.g. the pentadactyl limb of vertebreates. these limbs are used for flying, jumping, running. you would expect different bone structures between a flying or swimming vertebrate. however they are very similar. the same bones are adapted to carry out different functions- explanation is a common ancestor. the presence of homologous structures provides evidence for divergent evolutoin- how from a common ancestor, different species have evolved, each with adaptive features.

Answer 14

study of similarities and differences in proteins and other molecules that control life processes. some remain highly unchanged among species. slight changes that occur help to identify evolutionary links. the hypothesis of neutral evolution states that variability in the structure of a molecule doesn't affect its function- this is as variability occurs outside of the molecules functional regions. to discover how closely two species are related, molecular sequences of a particular molecule are compared, by looking at DNA vase order, or amino acid sequences, the number of differences are plotted against the rate the molecule undergoes neutral base pair substitutions. scientists can estimate the point as which the two shared a common ancestor.

Answer 15

between members of different species, for example a mouse has four legs, teeth, and fue whilst a bird has two legs, two wings, a beak, and feathers

Answer 16

between organisms within a species- humans vary in height, build, intelligence, skin colour

Answer 17

rose bush in sun will grow more. scars on the body

Answer 18

alleles- genes have different alleles. with a gene for a particular characteristic different alleles produce different effects mutations- changes to DNA base sequences lead to changes in the proteins made- can affect physical and metabolic characteristics Meiosis- gametes are produced by meiosis organisms that sexually reproduce- each gamete recieves half the genetic content of a parent cell. sexual reproduction: offspring inherit different alleles. chance

Answer 19

can only result in crtain values which fall into discrete groups. can be no inbetween values. determined purely by genetics. such as blood type or sex. represented in a bar chart, pie chart.

Answer 20

characteristic that can take on any value within a range. a graduation in values from one extreme to another. e.g. height and mass of plants and animals- controlled by many genes (polygenic). also influenced by environment. often plotted onto a histogram or a frequency table

Answer 21

when continuous variation data is plotted onto a graph, it results in a bell shaped curve known as a distribution curve. the mean, median, and mode are the same.

Answer 22

a measure of how spread out the data is. the higher the SD the greater the spread.

Answer 23

calculate the mean value of the data set subtract the mean value from every data piece square each value sum these values divide this sum value by the sample size square root this value

Answer 24

a feature of a living organism that increases its chances of survival and reproduction in its environment

Answer 25

a feature of a living organism that increases its chance of survival and reproduction in its environment. behaviour can be innate of acquired

Answer 26

feature that ensures the correct functioning of cellular processes

Answer 27

any physical structure that enhances the survival of the organism

Answer 28

shared ancestry, with similar underlying anatomy, may have similar or different functions. e.g. ex-vertebrate limbs (pentadactyl)

Answer 29

have different ancestries, dissimilar anatomies but similar functions. such as the butterfly wing and the bird wing.

Answer 30

involves related species diverging from a common ancestor and evolving distinct characteristics. relate to homologous structures.

Answer 31

occurs when unrelated species independently evolve similarities due to similar environmental or selection pressures. relates to analogous structures

Answer 32

the mechanism for evolution of a new species. there is variation in a population (alleles from mutation). the best adapted organisms in a population outcompete those that are less well adapted. they are selected y the environment to survive and reproduce. they pass on their favourable alleles to the next generation. over time the frequency of the alleles in the gene pool changes.

Answer 33

chemicals produced by a living organism which inhibit or kill bacteria without harming human tissue.

Answer 34

a resistant genus of bacteria becomes resistant- this is staphyloccocus (MRSA). it has a selective advantage with this allele, it therefore survives and reproduces. the allele for resistance arises from the plasmifs. bacteria become resistant due to mutation, the allele for resistance to penicilllin.

Answer 35

- limit the use of antibiotics - regularly change the antibiotic type - use two or more at a time

4.1.3 classification and evolution Flashcards

(59 cards)