AQA GCSE Biology - Paper 1 Questions And Answers Graded A+.
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AQA GCSE Biology - Paper 1
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AQA GCSE Biology - Paper 1
AQA GCSE Biology - Paper 1 Questions And Answers Graded A+.
What does a nucleus do? - correct answer. It contains genetic material and controls the activities of the cell
What does cytoplasm do? - correct answer. It's a gel-like substance where most of the chemical reactions happen....
AQA GCSE Biology - Paper 1 Questions
And Answers Graded A+.
What does a nucleus do? - correct answer. It contains genetic material and controls
the activities of the cell
What does cytoplasm do? - correct answer. 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 answer. It holds the cell together and
controls what goes in and out
What do mitochondria do? - correct answer. 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 answer. This is where protein synthesis takes place
- where proteins are made in the cell
What do cell walls do? - correct answer. They are made of cellulose and they support
and strengthen the cell
What does a vacuole do? - correct answer. It contains cell sap and helps maintain the
shape of the cell
What do chloroplasts do? - correct answer. 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 answer. 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 answer. A nucleus
What is the equation for magnification? - correct answer. Image size divided by actual
size
What is differentiation? - correct answer. The process by which a cell changes to
become specialised for its job
What are undifferentiated cells called? - correct answer. Stem cells
,What are sperm cells specialised for and how are they specialised? - correct answer.
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 answer.
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 answer.
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 answer.
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 answer. Coiled up lengths of DNA molecules that
are found in the nuclei
What do multicellular organisms use mitosis for? - correct answer. To grow or replace
cells that have been damaged
What are stem cells? - correct answer. 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 answer. In early human embryos or the bone
marrow of adults
What do embryonic stem cells do? - correct answer. 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 answer. 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 answer.
Glucose, water, oxygen and amino acids
, Name two substances that can't diffuse through cell membranes - correct answer.
Protein and starch
What is osmosis? - correct answer. 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
answer. 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 answer. 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 answer. 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 answer. 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 answer. Concentration gradient - the
steeper the gradient, the faster the rate
Temperature - the higher the temperature, the faster the rate (the particles have more
energy thus move around faster)
Surface area - the larger it is, the faster the rate
Diffusion distance - the shorter the distance, the faster the rate
Examples of active transport - correct answer. Plants = Root hairs absorb minerals
and water. Each branch of a root will be covered in tiny hairs, therefore increasing the
surface area for the absorption of minerals and water. The concentration of minerals is
usually higher in the root hair cells than in the soil around them, therefore they can't use
diffusion for this process.
Animals = Glucose is taken in from the gut and from kidney tubules.
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