AS-LEVEL
AS-LEVEL
BIOLOGY
BIOLOGY
NOTES
snaprevise.co.uk
, I have designed and compiled
these beautiful notes to
provide a detailed but concise
summary of this module.
I have spent a lot of time
perfecting the content as
well as the presentation to
make your learning as easy as
possible and less daunting.
A-LEVEL REVISION & EXAM
PREP IN A SNAP
Concise & exam High quality notes Created by A*
board specific videos and summaries students
Visit snaprevise.co.uk to find out more
DISCLAIMER
The information presented is no way produced
or endorsed by any exam board.
,INDEX
MODULE 2: FOUNDATIONS IN BIOLOGY ............................... 7
TOPIC 1: CELL STRUCTURE ......................................................................... 8
1. Microscopy ..................................................................................................................................... 9
2. Light & Electron Microscopy ...................................................................................................... 10
3. Cell Structure ............................................................................................................................... 13
4. Magnification Formula ................................................................................................................ 14
5. Magnification vs. Resolution ...................................................................................................... 14
6. Eukaryotic Cells & Cellular Components .................................................................................. 15
7. Organelles Involved in the Production & Secretion of Proteins ............................................. 18
8. Cytoskeleton ................................................................................................................................ 18
9. Structure & Ultrastructure of Prokaryotic & Eukaryotic Cells ................................................. 19
TOPIC 2: BIOLOGICAL MOLECULES ........................................................ 21
1. Hydrogen Bonding ..................................................................................................................... 22
2. Monomers & Polymers ......................................................................................................... 24
3. Biological Molecules and Their Chemical Elements ................................................................ 24
4 Glucose and Ribose.................................................................................................................... 25
5. Formation and Breakage of Glycosidic Bonds ......................................................................... 26
6. Starch, Glycogen & Cellulose ..................................................................................................... 27
7. Triglycerides and Phospholipids ................................................................................................ 28
8. The General Structure of an Amino Acid .................................................................................. 30
9. Dipeptides, Polypeptides and Peptide Bonds .......................................................................... 31
10. The Levels of Protein Structure ................................................................................................. 32
11. Globular and Fibrous Proteins ............................................................................................. 34
12. Inorganic Ions ............................................................................................................................. 35
13. Chemical Tests ............................................................................................................................ 35
14. Concentration of a Chemical Substance in a Solution ............................................................ 36
15. Thin Layer Chromatography ...................................................................................................... 37
TOPIC 3: NUCLEOTIDES & NUCLEIC ACIDS .......................................... 38
1. Nucleotides & Polynucleotides............................................................................................ 39
2. ADP & ATP.................................................................................................................................... 40
3. Deoxyribonucleic Acid (DNA) .................................................................................................... 40
3
, 4. Semi-Conservative DNA Replication ......................................................................................... 42
5. The Genetic Code ........................................................................................................................ 43
6. Transcription and Translation of Genes ................................................................................... 43
TOPIC 4: ENZYMES................................................................................................ 45
1. Enzymes & Catalysing Reactions ............................................................................................... 46
2. Enzyme Action ............................................................................................................................. 46
3. Factors Affecting Enzyme Activity .................................................................................................. 48
4. Coenzymes, Cofactors & Prosthetic Groups .................................................................................. 50
5. Inhibitors & Enzyme-Controlled Reactions ................................................................................... 51
TOPIC 5: BIOLOGICAL MEMBRANES ............................................................. 53
1. Role of Membranes .................................................................................................................... 54
2. The Fluid Mosaic Model.............................................................................................................. 54
3. Membrane Structure and Permeability .................................................................................... 55
4. The Movement Molecules Across Membranes ....................................................................... 55
TOPIC 6: CELL DIVISION, CELL DIVERSITY AND CELL
ORGANISATION ............................................................................ 58
1. The Cell Cycle .................................................................................................................................... 59
2. How the Cell Cycle is Regulated................................................................................................. 60
3. The Main Stages of Mitosis ........................................................................................................ 60
4. The Significance of Mitosis in Life Cycles .................................................................................. 63
5. The Significance of Meiosis in Life Cycles ................................................................................. 63
6. Stages of Meiosis......................................................................................................................... 64
7. Cells of Multicellular Organisms and their specialised Functions.......................................... 66
8. Tissues, Organs and Organ systems ......................................................................................... 67
9. Stem Cells.................................................................................................................................... 67
10. Erythrocytes & Neutrophils Derived from Stem Cells in Bone Marrow ................................ 68
11. Xylem Vessels & Phloem Sieve Tubes ....................................................................................... 68
12. The Potential of Stem Cells in Research & Medicine ............................................................... 69
MODULE 3:EXCHANGE AND TRANSPORT ............................ 71
TOPIC 1: EXCHANGE SURFACES ..................................................................... 72
1. The Need for Specialised Exchange Surfaces .......................................................................... 73
2. Efficient Exchange Surface ............................................................................................................. 74
3. Components of the Mammalian Gaseous Exchange System ................................................ 74
4. Ventilation in Mammals ............................................................................................................. 75
4
AS-LEVEL
BIOLOGY
BIOLOGY
NOTES
snaprevise.co.uk
, I have designed and compiled
these beautiful notes to
provide a detailed but concise
summary of this module.
I have spent a lot of time
perfecting the content as
well as the presentation to
make your learning as easy as
possible and less daunting.
A-LEVEL REVISION & EXAM
PREP IN A SNAP
Concise & exam High quality notes Created by A*
board specific videos and summaries students
Visit snaprevise.co.uk to find out more
DISCLAIMER
The information presented is no way produced
or endorsed by any exam board.
,INDEX
MODULE 2: FOUNDATIONS IN BIOLOGY ............................... 7
TOPIC 1: CELL STRUCTURE ......................................................................... 8
1. Microscopy ..................................................................................................................................... 9
2. Light & Electron Microscopy ...................................................................................................... 10
3. Cell Structure ............................................................................................................................... 13
4. Magnification Formula ................................................................................................................ 14
5. Magnification vs. Resolution ...................................................................................................... 14
6. Eukaryotic Cells & Cellular Components .................................................................................. 15
7. Organelles Involved in the Production & Secretion of Proteins ............................................. 18
8. Cytoskeleton ................................................................................................................................ 18
9. Structure & Ultrastructure of Prokaryotic & Eukaryotic Cells ................................................. 19
TOPIC 2: BIOLOGICAL MOLECULES ........................................................ 21
1. Hydrogen Bonding ..................................................................................................................... 22
2. Monomers & Polymers ......................................................................................................... 24
3. Biological Molecules and Their Chemical Elements ................................................................ 24
4 Glucose and Ribose.................................................................................................................... 25
5. Formation and Breakage of Glycosidic Bonds ......................................................................... 26
6. Starch, Glycogen & Cellulose ..................................................................................................... 27
7. Triglycerides and Phospholipids ................................................................................................ 28
8. The General Structure of an Amino Acid .................................................................................. 30
9. Dipeptides, Polypeptides and Peptide Bonds .......................................................................... 31
10. The Levels of Protein Structure ................................................................................................. 32
11. Globular and Fibrous Proteins ............................................................................................. 34
12. Inorganic Ions ............................................................................................................................. 35
13. Chemical Tests ............................................................................................................................ 35
14. Concentration of a Chemical Substance in a Solution ............................................................ 36
15. Thin Layer Chromatography ...................................................................................................... 37
TOPIC 3: NUCLEOTIDES & NUCLEIC ACIDS .......................................... 38
1. Nucleotides & Polynucleotides............................................................................................ 39
2. ADP & ATP.................................................................................................................................... 40
3. Deoxyribonucleic Acid (DNA) .................................................................................................... 40
3
, 4. Semi-Conservative DNA Replication ......................................................................................... 42
5. The Genetic Code ........................................................................................................................ 43
6. Transcription and Translation of Genes ................................................................................... 43
TOPIC 4: ENZYMES................................................................................................ 45
1. Enzymes & Catalysing Reactions ............................................................................................... 46
2. Enzyme Action ............................................................................................................................. 46
3. Factors Affecting Enzyme Activity .................................................................................................. 48
4. Coenzymes, Cofactors & Prosthetic Groups .................................................................................. 50
5. Inhibitors & Enzyme-Controlled Reactions ................................................................................... 51
TOPIC 5: BIOLOGICAL MEMBRANES ............................................................. 53
1. Role of Membranes .................................................................................................................... 54
2. The Fluid Mosaic Model.............................................................................................................. 54
3. Membrane Structure and Permeability .................................................................................... 55
4. The Movement Molecules Across Membranes ....................................................................... 55
TOPIC 6: CELL DIVISION, CELL DIVERSITY AND CELL
ORGANISATION ............................................................................ 58
1. The Cell Cycle .................................................................................................................................... 59
2. How the Cell Cycle is Regulated................................................................................................. 60
3. The Main Stages of Mitosis ........................................................................................................ 60
4. The Significance of Mitosis in Life Cycles .................................................................................. 63
5. The Significance of Meiosis in Life Cycles ................................................................................. 63
6. Stages of Meiosis......................................................................................................................... 64
7. Cells of Multicellular Organisms and their specialised Functions.......................................... 66
8. Tissues, Organs and Organ systems ......................................................................................... 67
9. Stem Cells.................................................................................................................................... 67
10. Erythrocytes & Neutrophils Derived from Stem Cells in Bone Marrow ................................ 68
11. Xylem Vessels & Phloem Sieve Tubes ....................................................................................... 68
12. The Potential of Stem Cells in Research & Medicine ............................................................... 69
MODULE 3:EXCHANGE AND TRANSPORT ............................ 71
TOPIC 1: EXCHANGE SURFACES ..................................................................... 72
1. The Need for Specialised Exchange Surfaces .......................................................................... 73
2. Efficient Exchange Surface ............................................................................................................. 74
3. Components of the Mammalian Gaseous Exchange System ................................................ 74
4. Ventilation in Mammals ............................................................................................................. 75
4
