GCSE Biology
What are the differences between plant and animal cells? ✔✔Plant
> has a cell wall
> only one vacuole
> chloroplasts
Animal
> no cell wall
> multiple vacuoles
> no chloroplasts
List all of the organelles which define an animal cell. ✔✔> nucleus
> cell membrane
> cytoplasm
> vacuoles
> mitochondria
What is the function of the nucleus? ✔✔contains genetic information contained in chromosomes
which are assembled into DNA
Which cell organelle is responsible for protein synthesis? ✔✔ribosomes
Which cell organelle contains chlorophyll and is the site of photosynthesis? ✔✔chloroplast
Where is the site of aerobic respiration in a cell? ✔✔mitochondria
What is the function of vacuoles? ✔✔storage > contain a solution
What is a cell wall made of? ✔✔cellulose
Describe the function of the cytoplasm. ✔✔clear jelly which contains dissolved substances >
site of many metabolic reactions
,How many nanometres are in a metre? ✔✔1 billion or 1x10^9
What are the differences between a light and electron microscope? ✔✔> electron microscopes
have a higher magnification and resolution
> in light microscopes, the source of the image is light waves whereas in electron microscopes
the source of the image is electron beams
> electron microscopes are more expensive
> the specimen has to be dead to view it under an electron microscope but a light microscope can
view either live or dead specimens
> in a light microscope the image is moving and in colour but in an electron microscope the
image is still and in black and white
> light microscope preparation is chemicals but electron microscope preparation is more
complex and the specimen has to be coated in materials and dehydrated
What are the differences between the scanning (SEM) and transmission electron microscopes
(TEM)? ✔✔> SEM is used to scan external features
> TEM is used to view internal features
What is the difference between magnification and resolution? ✔✔magnification tells us how
much bigger the image will appear, resolution is how clear the image is
What are the 7 characteristics of life? ✔✔MRSGREN
Movement
Respiration
Sensitivity
Growth
Reproduction
Excretion
Nutrition
, What is the equation for magnification? ✔✔magnification = image size / actual size
What features of a sperm cell make them suitable for sexual reproduction? ✔✔> flagellum
which helps them move towards the egg
> haploids (one set of chromosomes)
> mitochondria to give them energy from respiration to move
What are the differences between prokaryotic and eukaryotic cells? ✔✔prokaryotic cells do not
have DNA contained inside a nucleus or organelles
Why are viruses not considered living? ✔✔they cannot reproduce by themselves > which is one
of the MRSGREN requirements
How do bacteria divide? ✔✔binary fission
What are the 3 phases of the cell cycle? ✔✔1. Interphase
2. Mitosis
3. Cytokinesis
What are the 3 stages of interphase? ✔✔1. G1 > the cell carries out normal activities e.g
respiration
2. S > DNA replicates to form two copies of each chromosome
3. G2 > further growth occurs; organelles such as mitochondria replicate and the DNA is
checked for errors and any repairs are made
What happens during mitosis and cytokinesis? ✔✔Mitosis > the stage where the chromosomes
separate and the nucleus divides into 2 within the cell
Cytokinesis > the stage where cells physically divide into 2
What are stem cells? ✔✔undifferentiated cells with the potential to divide and produce new
specialised cells such as nerve cells or muscle cells
What are the differences between plant and animal cells? ✔✔Plant
> has a cell wall
> only one vacuole
> chloroplasts
Animal
> no cell wall
> multiple vacuoles
> no chloroplasts
List all of the organelles which define an animal cell. ✔✔> nucleus
> cell membrane
> cytoplasm
> vacuoles
> mitochondria
What is the function of the nucleus? ✔✔contains genetic information contained in chromosomes
which are assembled into DNA
Which cell organelle is responsible for protein synthesis? ✔✔ribosomes
Which cell organelle contains chlorophyll and is the site of photosynthesis? ✔✔chloroplast
Where is the site of aerobic respiration in a cell? ✔✔mitochondria
What is the function of vacuoles? ✔✔storage > contain a solution
What is a cell wall made of? ✔✔cellulose
Describe the function of the cytoplasm. ✔✔clear jelly which contains dissolved substances >
site of many metabolic reactions
,How many nanometres are in a metre? ✔✔1 billion or 1x10^9
What are the differences between a light and electron microscope? ✔✔> electron microscopes
have a higher magnification and resolution
> in light microscopes, the source of the image is light waves whereas in electron microscopes
the source of the image is electron beams
> electron microscopes are more expensive
> the specimen has to be dead to view it under an electron microscope but a light microscope can
view either live or dead specimens
> in a light microscope the image is moving and in colour but in an electron microscope the
image is still and in black and white
> light microscope preparation is chemicals but electron microscope preparation is more
complex and the specimen has to be coated in materials and dehydrated
What are the differences between the scanning (SEM) and transmission electron microscopes
(TEM)? ✔✔> SEM is used to scan external features
> TEM is used to view internal features
What is the difference between magnification and resolution? ✔✔magnification tells us how
much bigger the image will appear, resolution is how clear the image is
What are the 7 characteristics of life? ✔✔MRSGREN
Movement
Respiration
Sensitivity
Growth
Reproduction
Excretion
Nutrition
, What is the equation for magnification? ✔✔magnification = image size / actual size
What features of a sperm cell make them suitable for sexual reproduction? ✔✔> flagellum
which helps them move towards the egg
> haploids (one set of chromosomes)
> mitochondria to give them energy from respiration to move
What are the differences between prokaryotic and eukaryotic cells? ✔✔prokaryotic cells do not
have DNA contained inside a nucleus or organelles
Why are viruses not considered living? ✔✔they cannot reproduce by themselves > which is one
of the MRSGREN requirements
How do bacteria divide? ✔✔binary fission
What are the 3 phases of the cell cycle? ✔✔1. Interphase
2. Mitosis
3. Cytokinesis
What are the 3 stages of interphase? ✔✔1. G1 > the cell carries out normal activities e.g
respiration
2. S > DNA replicates to form two copies of each chromosome
3. G2 > further growth occurs; organelles such as mitochondria replicate and the DNA is
checked for errors and any repairs are made
What happens during mitosis and cytokinesis? ✔✔Mitosis > the stage where the chromosomes
separate and the nucleus divides into 2 within the cell
Cytokinesis > the stage where cells physically divide into 2
What are stem cells? ✔✔undifferentiated cells with the potential to divide and produce new
specialised cells such as nerve cells or muscle cells
