Paper 1 Exam Qs Flashcards
A heartbeat sound is described as ‘lub-dub’ what happens during the ‘lub’ at ventricular systole
atrioventricular valves close and blood leaves the ventricles
what monosaccharides are made from the breakdown of sucrose
alpha glucose
fructose
the enzyme microtubule depolymerase breaks down the spindle fibres in mitosis - at what stage will there be the most active enzymes
telophase
what is atrial fibrillation
irregular and rapid rate
summarise chloride shift
hydrogen carbonate ions movin out of red blood cells and chloride ions moving into red blood cells
state 2 differences between ADP and a DNA nucleotide
ADP has 2 phosphates WHEREAS DNA nucleotide has 1 phosphate
ADP has ribose WHEREAS DNA nucleotide has deoxyribose
ADP binds with a Pi to make ATP - what type of reaction is this
condensation (phosphorylation)
explain how the genetic code in the gene for a protein codes for that protein
3 bases code for amino acid
sequence of bases determines sequence of amino acids
code is non overlapping
explain how to calculate a diameter of the nucleus using a light microscope
use eyepiece graticule
calibrate eyepiece graticule with stage micrometer
measure the diameter in eyepiece graticule units
take repeat measurements and calculate a mean
using a transmission electron microscope, it was concluded that a WBC had stopped dividing at the G2 checkpoint - state 2 observations that would have led to this conclusion
no visible chromosomes
nuclear membrane present
during the DNA extraction practical, why do WBCs not need to be crushed before adding detergent
they have no cell wall to break
why is detergent used in DNA extraction
breaks down the phospholipid bilayer
what type of enzyme should be used in this practical
protease which breaks down histones
why would using standard deviation error bars improve confidence in a conclusion
SD shows spread of data compared to the mean
so reduces the effect of anomalies
suggest 3 reasons for an increase in antibiotic resistance over 5 years
not completing course of antibiotics
overprescription of antibiotics
natural selection
explain the importance of maintaining biodiversity for the discovery of new antibiotics
plants are an important source of drugs
so maintaining biodiversity increases the chance of finding new drugs
maintains genetic resource for the future
define synthetic biology
synthesis of new genes
