past paper questions Flashcards
which stage in the cell cycle would DNA polymerase be most active
S phase (when the cell replicates it own DNA and for mitosis)
what does DNA polymerase do
makes phosphodiester bonds between adjacent nucleotides
what does alcohol do to the cell surface membrane
contains OH- which change the PH of the membrane this denatures the proteins on the membrane causing it do break down, breaks down lipid bilayer properties dissolves the layers
what is ectopic heartbeat
irregular heart beat usually harmless
what is fibrillation
irregular and fast heart beat, the heart beats with no coordination so little blood cirulated
what is the spiracle in insects
respiratory openings found on the thorax and abdomen of insects.
what is the temperature coefficient
q10= Rt/R(T-10)
what does saturated/ unsaturated mean
full molecule no double bond, unsaturated contains double bonds
what is the name of the reaction in which lipase breaks fatty acids & glycerol
Hydrolysis
what does discontinuous mean in variation
limited amount of possible variations it can be
what does intraspecific mean in variation
variation amongst individuals of the same species
what does totipotent, pluripotent mean
totipotent- can different into any cell and organism
pluripotent- can differentiate into most cells but cannot make a whole organism
difference between mitosis and meiosis
mitosis is to do with growth, repair of cells so cells need to be genetically identical(diploid), meiosis forms sex cells/ gametes(haploid cells), more to do with genetic variation
what’s the role of the inner mass of embryonic stem cells
undifferentiated cells, which are a renewing force and can differentiate into any cell
what kind of cells are inner cell mass
pluripotent, cant make a whole organism , slightly differentiated into embryonic cells
