Baseline assesment Flashcards
Recessive
Both of these alleles need to be present in order for the recessive phenotype to be expressed
How does a mutation in the GALC gene result in a rchange in the enzyme galactocerbrosidase
- Gene = a sequence of bases that code for the sequence of amino acids in the protein
- Mutation will alter the codon
- THis may result in a different amino acid
- This may change the sshape of the protein/enzyme
- Therefore causing no synthesis of enzyme
Where does transcription occur?
Nucleus
(transcribe the DNA molecule onto an mRNA strand)
Where does translation occur?
Ribosome
(TRANSLATE the mRNA strand in the ribosome to arrange amino acids)
Protein synthesis process
- A complementary mRNA strand is made using DNA as a template
- The mRNA leaves the nucleus and attaches to the ribosome in the cytoplasm
- A triplet of bases on the mRNA code for specific amino acid
- The amino acids are delivered to the ribsome by tRNA
- Peptide bonds are formed between the amino acid to make the polypeptide
Why is it important that sperm has a nucleus that is haploid
Haploids have half the required chromosome complement
2. So at fertilisation the diploid number is restored
3. allows the mixing of alleles for genetic variation
Where is there likely to be a greater genetic diversity in the hybrid plants than in either of the two seperate spoecies
- Different alleles in each of the two populations
- Each population is adapted to live in different environmental conditions
- there will have been different mutations in each population
- Alleles from different species will mix
Suggest how natural selection has led to the evolution of these two different forms of the same species?
- Leopards (spotted fur, grasslands)
- Panthers (black fur, forests)
- Camoflagued in its environment
- More likely to catch prey (has a selective advantage)
- Therefore survive adulthood
- To breed
- and Pass on alleles to
- Offspring
- Change in allele frequency over generations
Explain why the piece of potato placed in 0.2mol dm-3 sucrose solution had the largest change in mass
- Due to high uptake of more water
- As higher water potential outside potato
- there was the largest difference in concentrations of solutions
Student suggested that there would be no change in the mass of a piece of potato placed in a sucrose solution of 0.75 moldm-3. Give an explanation for this suggestion
- (GRAPH)
- results were plotted onto a graph
- The line crossed the x-axis at 0.75 moldm-3
- no net movement of water at that point