2020 Paper 1 Flashcards
Explain the function of ATP hydrolyse
- (ATP to ADP + Pi ) Releases energy;
2. (energy) allows active transport of ions
Movement of Na+ out of the cell allows the absorption of glucose into the cell lining the ileum
Generates a conc grad for Na+ from ileum into cell
Na+ moving in by facilitated diffusion
Describe and explain 2 feature you would expect to find in a ell specialised for absorption
1) large numbers of Chanel proteins for active transport
2) large numbers of mitochondria so make more ATP
Describe and explain how amino acids join to form a polypeptide
NH2 group joins to COOH group to form a peptide bond
Explain differences in results for sample A and B
Triglycerides decrease because of the action of LIPASE
Triglycerides decrease because of hydrolysis
Triglycerides decrease because of digestion of ester bonds
Why did scientists heat sample to 70 degrees for 10 mins
To denature enzymes
So no further digestion
Describe the role of micelles in the absorption of fats into the cells lining the ileum
Micelles include bile salts and fatty acids
Make fatty acids more soluble in water
Carry fatty acids to cell of ileum.
Maintain high conc of fatty acids to cell
Fatty acids absorbed by diffusion
At this time the rate of blood flow has not yet started to increase in aorta but pressure in left ventricle is increasing
Semi luna valve is closed
Pressure in aorta higher than in ventricle
At Q on F3 there is a small increase in pressure and in rate of blood flow in the aorta. Explain how this happens and its importance
Elastic recoil
Maintains blood pressure
Right ventricle curve
Same pattern
Lower pressure
Heat rate of dog
167
Name two other variable the student should have kept constant during this investigation
Temp
Concentration of ethanol
Colorimeter and light absorbance
Higher absorbance = more anthocyanin
More membrane damage = more anthocyanin released
E + F greater than G as phospholipids dissolved in ethanol
E greater than F as acid denatures membrane proteins
No colorimeter. Describe a method to prepare colour standards and use them to give data fo the total anthocyanin extracted
Known conc of blueberry extract
Dilution series
Compare with colour standards to give conc
Describe the role of DNA polymerase in semi conservative replication of DNA
Joins adjacent nucleotides
Condensation reactions
Phosphodiester bonds
Describe how an enzyme can be phosphorylated
Attachment of inorganic phosphate
Released from hydrolysis of ATP to ADP and pi
Why higher than normal concentrations of cyclin D could result in a tumour
Shorter side interphase
Faster cell divisions
Group of abnormal cells
Why death of alveolar epithelium cells reduces gas exchange in human lungs
Reduced SA
Increased diffusion distance
Reduced rate of gas exchange
How one antibody can be specific to tick protein anf alpha gal
Have a similar structure
Antibody is complementary
Was it an earlier immune response to tick Protein that cause the allergic reaction
Exposure to tick protein is followed by increase in antibody
Secondary faster increase in antibody = memory cells
Antibody increases during allergic reaction
During allergic reaction total antibody increases more than alpha gal antibody
So may be other antibodies
Non coding base sequences and where they are positioned
DA that does not code for protein
Between genes
Phylogenetic tree
C
T
L
R
Evaluate how thus information affects the validity of the phylogenetic tree
More similar than with any other species
High variation in species T
Small sample
Null hypothesis ans stats test
No correlation between conc of CO2 and stomata density
Correlation coefficient
Increase in atmospheric CO2 conc could result in less transpiration evaluate
Increase in CO2 conc = decrease in stromata density
Decrease stomata = decrease transpiration
Don’t know size of stomata
Don’t know if leaf has changed
Don’t know how long stomata open for
Other factors affect transpiration rate
How mRNA is formed by transcription in eukaryotes
HB break One DNA strand acts as template Free RNA nucleotides align by complementary base pairing U = A C = G RNA polymerase joins nucleotides By phosphodiester bonds Pre-mRNA is spliced
Describe how a polypeptide if formed by translation of mRNA
MRNA attaches to ribosome
TRNA anticodon bind to complementary mRNA codons
TRNA brings specific amino acid
Amino acid join by peptide bonds
Use of ATP
TRNA released
Ribosome moves along mRNA to form the polypeptide
Define gene mutation and how they can have no effect or positive effect
Change in bases
Formation of new alleles
No effect = genetic code is degenerate
Positive effect = may result in increased chance of survival
Calculate time difference as a percentage decrease
33%
Does data in figur 6 show a linear relationship
No
9% per 5
1.42/1.8 % per 5
Calculate mean stomata density
171
Number of stomata per mm2 per 10 year period
2.7
