AQA GCSE Biology Paper 1
What does a nucleus do?
It contains genetic material and controls the activities of the cell
What does cytoplasm do?
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?
It holds the cell together and controls what goes in and out
What do mitochondria do?
These are where most of the reactions for aerobic respiration occur. Respiration
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
What do chloroplasts do?
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?
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?
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 specialized for its job
What are undifferentiated cells called?
Stem cells
What are sperm cells specialized for and how are they specialized?
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 specialized for and how are they specialized?
Rapid signaling - 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 specialized for and how are they specialized?
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 specialized for and how are they specialized?
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?
Coiled up lengths of DNA molecules that are found in the nuclei
What do multicellular organisms use mitosis for?
To grow or replace cells that have been damaged
What does a nucleus do?
It contains genetic material and controls the activities of the cell
What does cytoplasm do?
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?
It holds the cell together and controls what goes in and out
What do mitochondria do?
These are where most of the reactions for aerobic respiration occur. Respiration
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
What do chloroplasts do?
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?
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?
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 specialized for its job
What are undifferentiated cells called?
Stem cells
What are sperm cells specialized for and how are they specialized?
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 specialized for and how are they specialized?
Rapid signaling - 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 specialized for and how are they specialized?
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 specialized for and how are they specialized?
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?
Coiled up lengths of DNA molecules that are found in the nuclei
What do multicellular organisms use mitosis for?
To grow or replace cells that have been damaged
