[问答题]
Data was collected on the protein composition
gks5p,h:m9z rof venom samples taken from t
,i4h( afzy celr s tn-xom0;*8he Malayan Krait (
o0hcy8anz eft( is-;,mxr4l*B. candidus) found in three localities; Malaysia, Indonesia and Thailand. All samples were carefully transported and preserved at temperatures below 20$^{circ}$C. The graph shows the number of different types of protein found in each venom sample.
1.1.Identify the independent and dependent variables in this investigation.
1.2.Venom samples were collected from different snakes, in different localities. Suggest two controlled variables, other than temperature, that would support the collection of comparable samples.
Below are the results from gel electrophoresis of one group of venom proteins.
2.1.Identify the group of venom proteins shown.
2.2.Explain how proteins are separated using gel electrophoresis.
Different mice were envenomed with samples from each of the three localities. It was observed that the venom with the lowest neurotoxicity was from the Malayan krait sampled in Malaysia.
3.Suggest why it was important to transport venom samples at temperatures below 20$^{circ}$C.
4.List two advantages of using mice as model organisms for humans.
The venom samples were further analysed, and it was suggested that the Three Finger Toxins group (3FTx) of proteins contributed significantly to the neurotoxicity of the venom. This prompted a closer analysis of the different types of 3FTx proteins found in each venom sample. The data was presented in a graph.
5.Based on the data, suggest which type of 3FTx protein is most likely responsible for differences in the levels of toxicity observed between the different venom samples. Justify your answer.
