NOTES: Italics indicates NOT from the mark scheme (often means no
mark schemes relating to the spec point). These are taken instead
from the CIE A Level textbook, which occasionally includes extra
detail to help my own understanding. All others are directly copied
from CIE 9700 mark schemes.
Mark scheme abbreviations: I = ignore, A = accept, R = reject. A
semi-colon “;” separates marking points, which are sometimes
numbered. “AVP” = any valid point. See the start of any mark
scheme for full abbreviations.
1. Cell Structure (incl. Microscopy)
Nucleolus + nuclear envelope:
1 two membranes forming, nuclear envelope ;
A nuclear envelope is composed of a double membrane
2 nuclear pores too small to allow DNA to, pass through / escape ;
3 AVP ;
prevents DNA from being broken down (by enzymes)
I DNA damage by enzymes
protects DNA from hydrolytic enzymes
nuclear envelope is a barrier, between nucleus and, cytoplasm
Golgi:
Structure:
flattened sacs / cisternae ;
stack / layered / described ;
idea that each cisterna in stack is, separate / not interconnected ;
smooth (outer surface) / no ribosomes ;
close to, nucleus / RER ; single membrane ;
ref. to swollen ends to cisternae
Function:
modification of protein / glycosylation / described modification of
lipid
mark schemes relating to the spec point). These are taken instead
from the CIE A Level textbook, which occasionally includes extra
detail to help my own understanding. All others are directly copied
from CIE 9700 mark schemes.
Mark scheme abbreviations: I = ignore, A = accept, R = reject. A
semi-colon “;” separates marking points, which are sometimes
numbered. “AVP” = any valid point. See the start of any mark
scheme for full abbreviations.
1. Cell Structure (incl. Microscopy)
Nucleolus + nuclear envelope:
1 two membranes forming, nuclear envelope ;
A nuclear envelope is composed of a double membrane
2 nuclear pores too small to allow DNA to, pass through / escape ;
3 AVP ;
prevents DNA from being broken down (by enzymes)
I DNA damage by enzymes
protects DNA from hydrolytic enzymes
nuclear envelope is a barrier, between nucleus and, cytoplasm
Golgi:
Structure:
flattened sacs / cisternae ;
stack / layered / described ;
idea that each cisterna in stack is, separate / not interconnected ;
smooth (outer surface) / no ribosomes ;
close to, nucleus / RER ; single membrane ;
ref. to swollen ends to cisternae
Function:
modification of protein / glycosylation / described modification of
lipid
