OCR A LEVEL BIOLOGY PAPER 2 TEST PAPER
2026 QUESTIONS AND FULL ANSWER KEY
◉ Describe the nucleolus. Answer: Inside the nucleus
No membrane
Contains RNA
Where ribosomes are made
◉ Describe the rough endoplasmic reticulum (RER). Answer: -
Membranes continuous with nuclear envelope
-fluid-filled cavities called cisternae
-Ribosomes attached
-Produce proteins
-A transport system
◉ Describe the smooth endoplasmic reticulum (SER). Answer: -
membranes not continuous with nuclear membrane
-continuous with RER
-cisternae
-lipid enzymes
-absorption, synthesis and transport of lipids
-no ribosomes
,◉ Describe the Golgi Apparatus. Answer: -stack of membrane-bound
flattened sacs
-modify proteins (e.g. add sugar to make glycoproteins)
-proteins packaged into vesicles
◉ Describe lysosomes. Answer: -single membrane
-contain powerful hydrolytic enzymes
-Abundant in phagocytic cells
-can engulf old cell organelles
-keep enzymes separate from cell
◉ Describe mitochondria. Answer: -double membrane
-inner membrane folded into cristae
-fluid-filled matrix
-self-replicating
-ATP production
-abundant in cells with lots of metabolic activity (muscle, liver etc.)
◉ Describe chloroplasts. Answer: -double membrane
-only in plants
-thylakoids containing chlorophyll
,-each thylakoid stack called a granum
-Stroma - fluid-filled matrix
-loops of DNA and starch grains
-site of photosynthesis
-Abundant in palisade mesophyll layer
◉ Describe vacuole. Answer: -surrounded by tonoplast membrane
-contains water and solutes
-maintains stability (turgid when full)
-only in plants
◉ What type of cell wall do plants have?. Answer: cellulose
◉ What type of cell wall do bacteria have?. Answer: peptidoglycan
◉ What type of cell wall do fungi have?. Answer: chitin
◉ Describe the cellulose cell wall. Answer: -outside plasma
membrane
-bundles of cellulose fibres
-prevents cell from bursting when turgid
- strength and support
, - maintains cell shape
-permeable
-only in plants
◉ Describe cilia and undulipodia. Answer: -protrusions surrounded
by cell membrane
-contains microtubules
-formed from centrioles
-nearly all cells have cilia containing receptors
◉ What type of cell has cilia and why?. Answer: Epithelial cells have
cilia to move mucus
◉ What type of cell has undulipodium and why?. Answer: A sperm
cell has a undulipodium to move
◉ Describe ribosomes . What is the difference between the functions
of free ribosomes and RER ribosomes?. Answer: -no membrane
-made of ribosomal RNA
- made in nucleolus in two parts
-those bound to RER, synthesise proteins for use outside cell
- those free in cytoplasm, assemble proteins for use inside the cell
2026 QUESTIONS AND FULL ANSWER KEY
◉ Describe the nucleolus. Answer: Inside the nucleus
No membrane
Contains RNA
Where ribosomes are made
◉ Describe the rough endoplasmic reticulum (RER). Answer: -
Membranes continuous with nuclear envelope
-fluid-filled cavities called cisternae
-Ribosomes attached
-Produce proteins
-A transport system
◉ Describe the smooth endoplasmic reticulum (SER). Answer: -
membranes not continuous with nuclear membrane
-continuous with RER
-cisternae
-lipid enzymes
-absorption, synthesis and transport of lipids
-no ribosomes
,◉ Describe the Golgi Apparatus. Answer: -stack of membrane-bound
flattened sacs
-modify proteins (e.g. add sugar to make glycoproteins)
-proteins packaged into vesicles
◉ Describe lysosomes. Answer: -single membrane
-contain powerful hydrolytic enzymes
-Abundant in phagocytic cells
-can engulf old cell organelles
-keep enzymes separate from cell
◉ Describe mitochondria. Answer: -double membrane
-inner membrane folded into cristae
-fluid-filled matrix
-self-replicating
-ATP production
-abundant in cells with lots of metabolic activity (muscle, liver etc.)
◉ Describe chloroplasts. Answer: -double membrane
-only in plants
-thylakoids containing chlorophyll
,-each thylakoid stack called a granum
-Stroma - fluid-filled matrix
-loops of DNA and starch grains
-site of photosynthesis
-Abundant in palisade mesophyll layer
◉ Describe vacuole. Answer: -surrounded by tonoplast membrane
-contains water and solutes
-maintains stability (turgid when full)
-only in plants
◉ What type of cell wall do plants have?. Answer: cellulose
◉ What type of cell wall do bacteria have?. Answer: peptidoglycan
◉ What type of cell wall do fungi have?. Answer: chitin
◉ Describe the cellulose cell wall. Answer: -outside plasma
membrane
-bundles of cellulose fibres
-prevents cell from bursting when turgid
- strength and support
, - maintains cell shape
-permeable
-only in plants
◉ Describe cilia and undulipodia. Answer: -protrusions surrounded
by cell membrane
-contains microtubules
-formed from centrioles
-nearly all cells have cilia containing receptors
◉ What type of cell has cilia and why?. Answer: Epithelial cells have
cilia to move mucus
◉ What type of cell has undulipodium and why?. Answer: A sperm
cell has a undulipodium to move
◉ Describe ribosomes . What is the difference between the functions
of free ribosomes and RER ribosomes?. Answer: -no membrane
-made of ribosomal RNA
- made in nucleolus in two parts
-those bound to RER, synthesise proteins for use outside cell
- those free in cytoplasm, assemble proteins for use inside the cell
