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AQA GCSE BIOLOGY - PAPER 1 EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
Terms in this set (251)
What does a nucleus do? It contains genetic material and controls the activities of the cell
It's a gel-like substance where most of the chemical reactions happen. It
What does cytoplasm do?
contains enzymes that control these chemical reactions
What does a cell membrane do? It holds the cell together and controls what goes in and out
These are where most of the reactions for aerobic respiration occur. Respiration
What do mitochondria do?
transfers energy that the cell needs to work
What do ribosomes do? This is where protein synthesis takes place - where proteins are made in the cell
What do cell walls do? They are made of cellulose and they support and strengthen the cell
What does a vacuole do? It contains cell sap and helps maintain the shape of the cell
This is where photosynthesis occurs, which makes food for the plant. They
What do chloroplasts do?
contain chlorophyll - a green pigment - which absorbs light needed for
photosynthesis
Cytoplasm, cell membrane, cell wall, flagella, ribosomes, mitochondria, slime
What do bacterial cells contain? 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? A nucleus
What is the equation for magnification? Image size divided by actual size
What is differentiation? The process by which a cell changes to become specialised for its job
What are undifferentiated cells called? Stem cells
Reproduction - they transport the male DNA to the female DNA
What are sperm cells specialised for and -It has a flagella and a streamlined head to help it swim towards the egg
how are they specialised? -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
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, 3/25/25, 5:34 AQA GCSE Biology - Paper 1 |
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Rapid signalling - they carry electrical signals from one part of the body to another
What are nerve cells specialised for and -They are long to cover more distance
how are they specialised? -They have branched connections at their ends to connect to other nerve cells and
form a network throughout the body
Contraction - they need to contract quickly
What are muscle cells specialised for and
-They are long so they have space to contract
how are they specialised?
-They contain lots of mitochondria to generate the energy needed for contraction
Absorbing water and minerals
What are root hair cells specialised for and -They are cells on the surface of plant roots which grow into long hairs that stick out
how are they specialised? into the soil
-They have a large surface area for absorbing water and mineral ions from the soil
What are chromosomes? Coiled up lengths of DNA molecules that are found in the nuclei
What do multicellular organisms use mitosis To grow or replace cells that have been damaged
for?
They are undifferentiated cells that divide to produce lots more undifferentiated
What are stem cells?
cells. They then differentiate into different types of cell
Where are stem cells found? In early human embryos or the bone marrow of adults
1) Used to replace faulty cells in sick people - insulin-producing cells for
What do embryonic stem cells do? diabetes and nerve cells for paralysed spinal injuries
2)Used to replace faulty blood cells
Diffusion is the movement of particles from an area of high concentration to an area
What is diffusion?
of low concentration
Name the substances that can diffuse Glucose, water, oxygen and amino acids
through cell membranes
Name two substances that can't diffuse Protein and starch
through cell membranes
Osmosis is the passive movement of water molecules through a partially permeable
What is osmosis? 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 uses energy whereas diffusion doesn't. Active transport goes against
active transport and diffusion? the concentration gradient whereas diffusion goes along it
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
Adaptations of Exchange Surfaces
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 1) A single layer of surface cells
intestine are adapted for absorbing 2)A very good blood supply to assist quick absorption
digested food
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