AQA GCSE Biology - Paper 1
What does a nucleus do? - Correct Answers-It contains genetic material and controls the
activities of the cell
What does cytoplasm do? - Correct Answers-It's a gel-like substance where most of the
chemical reactions happen. It contains enzymes that control these chemical reactions
What does a cell membrane do? - Correct Answers-It holds the cell together and controls what
goes in and out
What do mitochondria do? - Correct Answers-These are where most of the reactions for
aerobic respiration occur. Respiration transfers energy that the cell needs to work
What do ribosomes do? - Correct Answers-This is where protein synthesis takes place - where
proteins are made in the cell
What do cell walls do? - Correct Answers-They are made of cellulose and they support and
strengthen the cell
What does a vacuole do? - Correct Answers-It contains cell sap and helps maintain the shape of
the cell
What do chloroplasts do? - Correct Answers-This is where photosynthesis occurs, which makes
food for the plant. They contain chlorophyll - a green pigment - which absorbs light needed for
photosynthesis
What do bacterial cells contain? - Correct Answers-Cytoplasm, cell membrane, cell wall, flagella,
ribosomes, mitochondria, slime capsule, plasmids (small rings of DNA) and a single circular
strand of DNA that floats freely in the cytoplasm
What do bacterial cells NOT contain? - Correct Answers-A nucleus
What is the equation for magnification? - Correct Answers-Image size divided by actual size
What is differentiation? - Correct Answers-The process by which a cell changes to become
specialised for its job
,What are undifferentiated cells called? - Correct Answers-Stem cells
What are sperm cells specialised for and how are they specialised? - Correct Answers-
Reproduction - they transport the male DNA to the female DNA
-It has a flagella and a streamlined head to help it swim towards the egg
-There are lots of mitochondria in the cell to provide the energy needed
-It carries enzymes in its head to help digest through the egg cell membranes
What are nerve cells specialised for and how are they specialised? - Correct Answers-Rapid
signalling - they carry electrical signals from one part of the body to another
-They are long to cover more distance
-They have branched connections at their ends to connect to other nerve cells and form a
network throughout the body
What are muscle cells specialised for and how are they specialised? - Correct Answers-
Contraction - they need to contract quickly
-They are long so they have space to contract
-They contain lots of mitochondria to generate the energy needed for contraction
What are root hair cells specialised for and how are they specialised? - Correct Answers-
Absorbing water and minerals
-They are cells on the surface of plant roots which grow into long hairs that stick out into the
soil
-They have a large surface area for absorbing water and mineral ions from the soil
What are chromosomes? - Correct Answers-Coiled up lengths of DNA molecules that are found
in the nuclei
What do multicellular organisms use mitosis for? - Correct Answers-To grow or replace cells
that have been damaged
What are stem cells? - Correct Answers-They are undifferentiated cells that divide to produce
lots more undifferentiated cells. They then differentiate into different types of cell
Where are stem cells found? - Correct Answers-In early human embryos or the bone marrow of
adults
What do embryonic stem cells do? - Correct Answers-1) Used to replace faulty cells in sick
people - insulin-producing cells for diabetes and nerve cells for paralysed spinal injuries
2) Used to replace faulty blood cells
, What is diffusion? - Correct Answers-Diffusion is the movement of particles from an area of
high concentration to an area of low concentration
Name the substances that can diffuse through cell membranes - Correct Answers-Glucose,
water, oxygen and amino acids
Name two substances that can't diffuse through cell membranes - Correct Answers-Protein and
starch
What is osmosis? - Correct Answers-Osmosis is the passive movement of water molecules
through a partially permeable cell membrane from an area of high water concentration to an
area of low water concentration
What are the two main differences between active transport and diffusion? - Correct Answers-
Active transport uses energy whereas diffusion doesn't. Active transport goes against the
concentration gradient whereas diffusion goes along it
Adaptations of Exchange Surfaces - Correct Answers-1) Large surface area - lots of substances
can diffuse at once
2) Lots of blood vessels - to get stuff into and out of the blood quickly
3) Thin membrane - short distance for substances to diffuse
4) Often ventilated - air moves in & out
Give two ways that the villi in the small intestine are adapted for absorbing digested food -
Correct Answers-1) A single layer of surface cells
2) A very good blood supply to assist quick absorption
Explain how the leaves are adapted to maximise the amount of carbon dioxide that gets into
their cells - Correct Answers-1) The exchange surface in a leaf is covered in stomata which the
carbon dioxide diffuses through
2) The leaf has a flattened shape which increases the area of its exchange surface, therefore it's
more effective
3) The walls of the cells inside the leaf act as another exchange surface
4) The air spaces inside the leaf increase the area of the exchange surface which increases the
chance for carbon dioxide to enter the cells
What affects the rate of diffusion? - Correct Answers-Concentration gradient - the steeper the
gradient, the faster the rate
Temperature - the higher the temperature, the faster the rate (the particles have more energy
What does a nucleus do? - Correct Answers-It contains genetic material and controls the
activities of the cell
What does cytoplasm do? - Correct Answers-It's a gel-like substance where most of the
chemical reactions happen. It contains enzymes that control these chemical reactions
What does a cell membrane do? - Correct Answers-It holds the cell together and controls what
goes in and out
What do mitochondria do? - Correct Answers-These are where most of the reactions for
aerobic respiration occur. Respiration transfers energy that the cell needs to work
What do ribosomes do? - Correct Answers-This is where protein synthesis takes place - where
proteins are made in the cell
What do cell walls do? - Correct Answers-They are made of cellulose and they support and
strengthen the cell
What does a vacuole do? - Correct Answers-It contains cell sap and helps maintain the shape of
the cell
What do chloroplasts do? - Correct Answers-This is where photosynthesis occurs, which makes
food for the plant. They contain chlorophyll - a green pigment - which absorbs light needed for
photosynthesis
What do bacterial cells contain? - Correct Answers-Cytoplasm, cell membrane, cell wall, flagella,
ribosomes, mitochondria, slime capsule, plasmids (small rings of DNA) and a single circular
strand of DNA that floats freely in the cytoplasm
What do bacterial cells NOT contain? - Correct Answers-A nucleus
What is the equation for magnification? - Correct Answers-Image size divided by actual size
What is differentiation? - Correct Answers-The process by which a cell changes to become
specialised for its job
,What are undifferentiated cells called? - Correct Answers-Stem cells
What are sperm cells specialised for and how are they specialised? - Correct Answers-
Reproduction - they transport the male DNA to the female DNA
-It has a flagella and a streamlined head to help it swim towards the egg
-There are lots of mitochondria in the cell to provide the energy needed
-It carries enzymes in its head to help digest through the egg cell membranes
What are nerve cells specialised for and how are they specialised? - Correct Answers-Rapid
signalling - they carry electrical signals from one part of the body to another
-They are long to cover more distance
-They have branched connections at their ends to connect to other nerve cells and form a
network throughout the body
What are muscle cells specialised for and how are they specialised? - Correct Answers-
Contraction - they need to contract quickly
-They are long so they have space to contract
-They contain lots of mitochondria to generate the energy needed for contraction
What are root hair cells specialised for and how are they specialised? - Correct Answers-
Absorbing water and minerals
-They are cells on the surface of plant roots which grow into long hairs that stick out into the
soil
-They have a large surface area for absorbing water and mineral ions from the soil
What are chromosomes? - Correct Answers-Coiled up lengths of DNA molecules that are found
in the nuclei
What do multicellular organisms use mitosis for? - Correct Answers-To grow or replace cells
that have been damaged
What are stem cells? - Correct Answers-They are undifferentiated cells that divide to produce
lots more undifferentiated cells. They then differentiate into different types of cell
Where are stem cells found? - Correct Answers-In early human embryos or the bone marrow of
adults
What do embryonic stem cells do? - Correct Answers-1) Used to replace faulty cells in sick
people - insulin-producing cells for diabetes and nerve cells for paralysed spinal injuries
2) Used to replace faulty blood cells
, What is diffusion? - Correct Answers-Diffusion is the movement of particles from an area of
high concentration to an area of low concentration
Name the substances that can diffuse through cell membranes - Correct Answers-Glucose,
water, oxygen and amino acids
Name two substances that can't diffuse through cell membranes - Correct Answers-Protein and
starch
What is osmosis? - Correct Answers-Osmosis is the passive movement of water molecules
through a partially permeable cell membrane from an area of high water concentration to an
area of low water concentration
What are the two main differences between active transport and diffusion? - Correct Answers-
Active transport uses energy whereas diffusion doesn't. Active transport goes against the
concentration gradient whereas diffusion goes along it
Adaptations of Exchange Surfaces - Correct Answers-1) Large surface area - lots of substances
can diffuse at once
2) Lots of blood vessels - to get stuff into and out of the blood quickly
3) Thin membrane - short distance for substances to diffuse
4) Often ventilated - air moves in & out
Give two ways that the villi in the small intestine are adapted for absorbing digested food -
Correct Answers-1) A single layer of surface cells
2) A very good blood supply to assist quick absorption
Explain how the leaves are adapted to maximise the amount of carbon dioxide that gets into
their cells - Correct Answers-1) The exchange surface in a leaf is covered in stomata which the
carbon dioxide diffuses through
2) The leaf has a flattened shape which increases the area of its exchange surface, therefore it's
more effective
3) The walls of the cells inside the leaf act as another exchange surface
4) The air spaces inside the leaf increase the area of the exchange surface which increases the
chance for carbon dioxide to enter the cells
What affects the rate of diffusion? - Correct Answers-Concentration gradient - the steeper the
gradient, the faster the rate
Temperature - the higher the temperature, the faster the rate (the particles have more energy
