Biology Revision Notes – Term 1
This includes:
4.1 Cell biology
4.1.1 Cell structure
4.1.3 Transport in cells
4.2 Organisation
4.2.1 Principles of organisation
4.2.2 Animal tissues, organs and organ systems (up to 4.2.2.4 Coronary heart disease: a
non-communicable disease)
Colour coding:
Green Highlighter – stuff writt en word for word from the spec
Pink Highlighter – key & important words (and phrases)
4.1 Cell Biology
4.1.1 Cell Structure
4.1.1.1 Eukaryotes and prokaryotes
Eukaryotic cells are complex
Eukaryotic cells all have a cell membrane, cytoplasm and genetic material that is enclosed in
a nucleus
Genetic material is also known as DNA, and it is stored in forms of chromosomes, within the
nucleus
Plants, animals, fungi are all examples of eukaryotes
Bacteria are single-celled living organisms
They are way smaller than eukaryotes
Bacterial cells are called prokaryotes
, A prokaryote is a prokaryotic cell – it’s a single celled organism
They contain small rings of DNA – plasmids and their genetic material is not enclosed in a
nucleus but is freely moving around cytoplasm in a single loop
Bacteria have cytoplasm and a cell membrane surrounded by a cell wall
Bacterial cells sometimes have slime capsule and flagella – to swim (2nd)
The order of sizes goes as eukaryotic cells, prokaryotic cells, viruses, DNA, small molecule
A typical bacterial cell would have:
o Slime capsule – protects the cell
o Cell wall – its not made out of cellulose like in plants
o Cell membrane
o Plasmids – contain genetic code for specific features
o Flagella – long proteins, used for movement
o Genetic material – it’s a single strand of DNA, not enclosed in a nucleus
o Cytoplasm
4.1.1.2 Animal and plant cells
Plant and animal cells are eukaryotes
Different parts of the cell are called subcellular structures or organeles
Parts of animal cells + their functions:
o Nucleus – controls all the activities of the cell, surrounded by a nuclear membrane.
Contains genetic material in the form of chromosomes
o Cytoplasm – liquid gel where most of the organelles are suspended and where most
of the chemical reactions take place
o Cell membrane – controls the passage of the substances in and out of the cell
o Mitochondria – releases energy for the cell through a process of aerobic respiration
o Ribosomes – makes the proteins, through protein synthesis
Plant cells have all the previous subcellular structures, as well as:
o Cell wall – supports and strengthens the cell (made of cellulose)
o Vacuole – contains the cell sap, needed to keep cell rigid
o Chloroplasts (not always present) – contain chlorophyll needed for photosynthesis,
which converts sunlight into glucose
Required practical activity 1: use a light microscope to observe, draw and label a selection
of plant and animal cells. A magnification scale must be included.
This includes:
4.1 Cell biology
4.1.1 Cell structure
4.1.3 Transport in cells
4.2 Organisation
4.2.1 Principles of organisation
4.2.2 Animal tissues, organs and organ systems (up to 4.2.2.4 Coronary heart disease: a
non-communicable disease)
Colour coding:
Green Highlighter – stuff writt en word for word from the spec
Pink Highlighter – key & important words (and phrases)
4.1 Cell Biology
4.1.1 Cell Structure
4.1.1.1 Eukaryotes and prokaryotes
Eukaryotic cells are complex
Eukaryotic cells all have a cell membrane, cytoplasm and genetic material that is enclosed in
a nucleus
Genetic material is also known as DNA, and it is stored in forms of chromosomes, within the
nucleus
Plants, animals, fungi are all examples of eukaryotes
Bacteria are single-celled living organisms
They are way smaller than eukaryotes
Bacterial cells are called prokaryotes
, A prokaryote is a prokaryotic cell – it’s a single celled organism
They contain small rings of DNA – plasmids and their genetic material is not enclosed in a
nucleus but is freely moving around cytoplasm in a single loop
Bacteria have cytoplasm and a cell membrane surrounded by a cell wall
Bacterial cells sometimes have slime capsule and flagella – to swim (2nd)
The order of sizes goes as eukaryotic cells, prokaryotic cells, viruses, DNA, small molecule
A typical bacterial cell would have:
o Slime capsule – protects the cell
o Cell wall – its not made out of cellulose like in plants
o Cell membrane
o Plasmids – contain genetic code for specific features
o Flagella – long proteins, used for movement
o Genetic material – it’s a single strand of DNA, not enclosed in a nucleus
o Cytoplasm
4.1.1.2 Animal and plant cells
Plant and animal cells are eukaryotes
Different parts of the cell are called subcellular structures or organeles
Parts of animal cells + their functions:
o Nucleus – controls all the activities of the cell, surrounded by a nuclear membrane.
Contains genetic material in the form of chromosomes
o Cytoplasm – liquid gel where most of the organelles are suspended and where most
of the chemical reactions take place
o Cell membrane – controls the passage of the substances in and out of the cell
o Mitochondria – releases energy for the cell through a process of aerobic respiration
o Ribosomes – makes the proteins, through protein synthesis
Plant cells have all the previous subcellular structures, as well as:
o Cell wall – supports and strengthens the cell (made of cellulose)
o Vacuole – contains the cell sap, needed to keep cell rigid
o Chloroplasts (not always present) – contain chlorophyll needed for photosynthesis,
which converts sunlight into glucose
Required practical activity 1: use a light microscope to observe, draw and label a selection
of plant and animal cells. A magnification scale must be included.
