IB Biology Topic 1 paper 1 past paper
questions and 100% making scheme 25/2026
Cell theory states - Answer 1. all living things are composed of cells
2. cells are the basic units of structure and function in living things
3. all cells are produced from other cells
Evidence for cell theory - Answer 1. The use of a microscope
2. Cell lysis experiment (using a centrifuge) which has resulted in anything smaller than a cell, not
surviving on its own
3. Louis Pasteur's Chicken broth experiment (1860s)
Exceptions to the cell theory - Answer Striated muscle fibres
(Aseptate) fungal hyphae
Giant Algae
Magnification - Answer Image size/actual size
Definition of a cell - Answer the basic structural and functional unit of all living organisms
Definition of prokaryote - Answer a single-celled organism without a nucleus or membrane-bound
organelles
Organelles in prokaryotes - Answer cell wall, cytoplasm, Escherichia coli (E. coli), flagella, nucleoid, pili,
plasma membrane, ribosomes
Definition of Eukaryotes - Answer
Organelles in eukaryotes - Answer nucleus, plasma membrane, free ribosomes, rough endoplasmic
reticulum, golgi apparatus, cytoplasm, lysosome, mitchondria
, Function of the nucleus - Answer contains the cell's DNA
Function of the plasma membrane - Answer controls movement of materials in and out of the cell
Function of the free ribosomes - Answer synthesis of proteins used inside the cell
Function of the rough endoplasmic reticulum - Answer synthesis of proteins used outside the cell
Function of the golgi apparatus - Answer Storage, modification and package of proteins
Function of the cytoplasm - Answer 1. contains the organelles
2. allows metabolic reactions to occur
Function of the lysosome - Answer 1. contains digestive enzymes
2. fuses with vesicles containing damaged organelles
Function of the mitochondria - Answer the site of aerobic respiration - production of ATP
Function of vesicles - Answer transportation of materials inside the cell
Function of the flagella - Answer enables movement with its whip-like structures with a core of
microtubules
Function of the pili - Answer allows bacteria to attach to things with its hair-like protein structures
Definition of chromatin - Answer uncoiled chromosomes
Definition of cisterna - Answer flattened membrane sacs
questions and 100% making scheme 25/2026
Cell theory states - Answer 1. all living things are composed of cells
2. cells are the basic units of structure and function in living things
3. all cells are produced from other cells
Evidence for cell theory - Answer 1. The use of a microscope
2. Cell lysis experiment (using a centrifuge) which has resulted in anything smaller than a cell, not
surviving on its own
3. Louis Pasteur's Chicken broth experiment (1860s)
Exceptions to the cell theory - Answer Striated muscle fibres
(Aseptate) fungal hyphae
Giant Algae
Magnification - Answer Image size/actual size
Definition of a cell - Answer the basic structural and functional unit of all living organisms
Definition of prokaryote - Answer a single-celled organism without a nucleus or membrane-bound
organelles
Organelles in prokaryotes - Answer cell wall, cytoplasm, Escherichia coli (E. coli), flagella, nucleoid, pili,
plasma membrane, ribosomes
Definition of Eukaryotes - Answer
Organelles in eukaryotes - Answer nucleus, plasma membrane, free ribosomes, rough endoplasmic
reticulum, golgi apparatus, cytoplasm, lysosome, mitchondria
, Function of the nucleus - Answer contains the cell's DNA
Function of the plasma membrane - Answer controls movement of materials in and out of the cell
Function of the free ribosomes - Answer synthesis of proteins used inside the cell
Function of the rough endoplasmic reticulum - Answer synthesis of proteins used outside the cell
Function of the golgi apparatus - Answer Storage, modification and package of proteins
Function of the cytoplasm - Answer 1. contains the organelles
2. allows metabolic reactions to occur
Function of the lysosome - Answer 1. contains digestive enzymes
2. fuses with vesicles containing damaged organelles
Function of the mitochondria - Answer the site of aerobic respiration - production of ATP
Function of vesicles - Answer transportation of materials inside the cell
Function of the flagella - Answer enables movement with its whip-like structures with a core of
microtubules
Function of the pili - Answer allows bacteria to attach to things with its hair-like protein structures
Definition of chromatin - Answer uncoiled chromosomes
Definition of cisterna - Answer flattened membrane sacs
