Images & Animations — AQA A-level Biology | Random Walker

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Phosphodiester Bond

Phosphodiester Bond SVG

Peptide Bond

Peptide Bond SVG

Monomers and Polymers

Monomers and Polymers SVG

Hydrolysis of Starch

Hydrolysis of Starch SVG

Hydrolysis of a Polypeptide

Hydrolysis of a Polypeptide SVG

Benedict's Test Colours

Benedict's Test Colours SVG

Iodine Test for Starch

Iodine Test for Starch SVG

α-Glucose and β-Glucose

α-Glucose and β-Glucose SVG

Maltose and the 1-4 Glycosidic Bond

Maltose and the 1-4 Glycosidic Bond SVG

Amylose

Amylose SVG

Amylopectin

Amylopectin SVG

Glycogen Structure

Glycogen Structure SVG

Cellulose Structure

Cellulose Structure SVG

Mannan Monomer and Polymer

Mannan Monomer and Polymer SVG

Lipid Digestion

Lipid Digestion SVG

Fluid-Mosaic Model

Fluid-Mosaic Model SVG

Emulsion Test for Lipids

Emulsion Test for Lipids SVG

Formation of a Triglyceride

Formation of a Triglyceride SVG

Glycerol and a Fatty Acid

Glycerol and a Fatty Acid SVG

Phospholipid Structure

Phospholipid Structure SVG

Saturated and Unsaturated Fatty Acids

Saturated and Unsaturated Fatty Acids SVG

Amino Acid Structure

Amino Acid Structure SVG

Primary Protein Structure

Primary Protein Structure SVG

Alpha Helix

Alpha Helix SVG

Beta Pleated Sheet

Beta Pleated Sheet SVG

Tertiary Protein Structure

Tertiary Protein Structure SVG

Quaternary Protein Structure

Quaternary Protein Structure SVG

Biuret Test

Biuret Test SVG

Haemoglobin Structure

Haemoglobin Structure SVG

The 20 Amino Acids

The 20 Amino Acids SVG

Activation Energy

Activation Energy SVG

Induced-Fit Model

Induced-Fit Model SVG

Rate vs Enzyme Concentration

Rate vs Enzyme Concentration SVG

Rate vs Substrate Concentration

Rate vs Substrate Concentration SVG

Competitive and Non-Competitive Inhibitors

Competitive and Non-Competitive Inhibitors SVG

Rate vs pH

Rate vs pH SVG

Rate vs Temperature

Rate vs Temperature SVG

Initial Rate from a Tangent

Initial Rate from a Tangent SVG

Nucleotide Structure

Nucleotide Structure SVG

DNA Structure

DNA Structure PNG

Semi-Conservative Replication

Semi-Conservative Replication SVG

DNA Replication Summary

DNA Replication Summary SVG

Three Models of DNA Replication

Three Models of DNA Replication SVG

Meselson–Stahl Results

Meselson–Stahl Results SVG

Three Models of Replication (A, B, C)

Three Models of Replication (A, B, C) SVG

DNA Density Bands Over Generations

DNA Density Bands Over Generations SVG

ATP Structure

ATP Structure SVG

ATP Hydrolysis & Condensation

ATP Hydrolysis & Condensation SVG

Glucose / Amino Acid Absorption (Co-transport)

Glucose / Amino Acid Absorption (Co-transport) SVG

Hydrogen Bonds Between Water Molecules

Hydrogen Bonds Between Water Molecules SVG

Cohesion in a Xylem Vessel

Cohesion in a Xylem Vessel SVG

Surface Tension

Surface Tension SVG

Prokaryotic Cell Structure

Prokaryotic Cell Structure PNG

Virus Structure

Virus Structure SVG

Magnification and Resolution

Magnification and Resolution SVG

Magnification Practice Cell

Magnification Practice Cell SVG

Cell Fractionation

Cell Fractionation SVG

Ultracentrifugation

Ultracentrifugation SVG

Chloroplasts Centrifuged With and Without Detergent

Chloroplasts Centrifuged With and Without Detergent SVG

The Cell Cycle

The Cell Cycle SVG

Stages of Mitosis

Stages of Mitosis SVG

Prophase

Prophase SVG

Metaphase

Metaphase SVG

Anaphase

Anaphase SVG

Telophase

Telophase SVG

Calculating the Mitotic Index

Calculating the Mitotic Index SVG

Binary Fission

Binary Fission SVG

Root Tip Squash Field of View

Root Tip Squash Field of View SVG

Potato Cylinders in Sucrose (RP3)

Potato Cylinders in Sucrose (RP3) SVG

Water Potential Calibration Curve (RP3)

Water Potential Calibration Curve (RP3) SVG

Membrane Permeability vs Temperature (RP4)

Membrane Permeability vs Temperature (RP4) SVG

Visking Tubing Osmometer

Visking Tubing Osmometer SVG

Pigment Release with Different Solvents

Pigment Release with Different Solvents SVG

Antigen

Antigen SVG

Antigen Variability

Antigen Variability SVG

Phagocytosis

Phagocytosis SVG

Cellular Response (T Lymphocytes)

Cellular Response (T Lymphocytes) SVG

B Cell with Antibodies

B Cell with Antibodies SVG

Humoral Response (B Lymphocytes)

Humoral Response (B Lymphocytes) SVG

Antibody Structure

Antibody Structure SVG

Primary vs Secondary Immune Response

Primary vs Secondary Immune Response SVG

Immune Response Overview

Immune Response Overview SVG

HIV Structure

HIV Structure SVG

HIV Replication in Helper T Cells

HIV Replication in Helper T Cells SVG

Antibody-Drug Conjugate (Cancer Treatment)

Antibody-Drug Conjugate (Cancer Treatment) SVG

Pregnancy Test (Monoclonal Antibody)

Pregnancy Test (Monoclonal Antibody) SVG

ELISA Test (Indirect)

ELISA Test (Indirect) SVG

Lateral Flow Antibody Test

Lateral Flow Antibody Test SVG

SA:V Ratio — Cube and Cuboid Comparison

SA:V Ratio — Cube and Cuboid Comparison SVG

Amoeba — Gas Exchange

Amoeba — Gas Exchange SVG

Insect Tracheal System

Insect Tracheal System SVG

Fish Gill Structure

Fish Gill Structure SVG

Counter-current Flow in Fish Gills

Counter-current Flow in Fish Gills SVG

Plant Leaf Gas Exchange

Plant Leaf Gas Exchange SVG

Human Lung Structure

Human Lung Structure SVG

Alveolar Adaptations

Alveolar Adaptations SVG

Inspiration (Breathing In)

Inspiration (Breathing In) SVG

Expiration (Breathing Out)

Expiration (Breathing Out) SVG

Smoking and FEV₁

Smoking and FEV₁ SVG

Digestive System Structure

Digestive System Structure SVG

Carbohydrate Digestion

Carbohydrate Digestion SVG

Protein Digestion

Protein Digestion SVG

Micelle Structure

Micelle Structure SVG

Villi and Microvilli

Villi and Microvilli SVG

Lipid Absorption

Lipid Absorption SVG

Heart Structure

Heart Structure SVG

Cardiac Cycle

Cardiac Cycle SVG

Artery vs Vein Structure

Artery vs Vein Structure SVG

Capillary Structure

Capillary Structure SVG

Double Circulatory System

Double Circulatory System SVG

Tissue Fluid Formation (Arterial End)

Tissue Fluid Formation (Arterial End) SVG

Tissue Fluid Formation (Venous End)

Tissue Fluid Formation (Venous End) SVG

Lymphatic Return

Lymphatic Return SVG

Dissociation Curve after Nitrite Exposure

Dissociation Curve after Nitrite Exposure SVG

Left Side of the Heart (Valve A)

Left Side of the Heart (Valve A) SVG

Xylem Structure

Xylem Structure SVG

Potometer

Potometer SVG

Xylem Vessel Structure

Xylem Vessel Structure SVG

Potometer

Potometer SVG

Transpiration Over 24 Hours

Transpiration Over 24 Hours SVG

Phloem Structure

Phloem Structure SVG

Phloem Structure

Phloem Structure SVG

Phloem Cell Detail

Phloem Cell Detail SVG

Mass Flow Hypothesis Animation VIDEO

Watch on YouTube

Radioactive Tracer in Tomato Plants

Radioactive Tracer in Tomato Plants SVG

DNA, Histones and Chromosomes

DNA, Histones and Chromosomes SVG

A Gene on a DNA Molecule

A Gene on a DNA Molecule SVG

Locus on Homologous Chromosomes

Locus on Homologous Chromosomes SVG

Splicing of Pre-mRNA

Splicing of Pre-mRNA SVG

Eukaryotic vs Prokaryotic Genes

Eukaryotic vs Prokaryotic Genes SVG

Transcription and Translation Overview

Transcription and Translation Overview SVG

Transcription

Transcription SVG

Pre-mRNA Splicing

Pre-mRNA Splicing SVG

Translation

Translation SVG

mRNA Structure

mRNA Structure PNG

tRNA Structure

tRNA Structure PNG

Non-Disjunction

Non-Disjunction PNG

Meiosis I

Meiosis I SVG

Meiosis II

Meiosis II SVG

Crossing Over

Crossing Over SVG

Independent Segregation

Independent Segregation SVG

Directional Selection

Directional Selection SVG

Stabilising Selection (Birth Weight)

Stabilising Selection (Birth Weight) SVG

Zones of Inhibition (RP6)

Zones of Inhibition (RP6) SVG

Phylogenetic Tree

Phylogenetic Tree SVG

Reading a Phylogenetic Tree

Reading a Phylogenetic Tree SVG

Immunological Comparisons

Immunological Comparisons SVG

Standard Deviation: Narrow and Wide Spread

Standard Deviation: Narrow and Wide Spread SVG

Normal Distribution (±2 SD)

Normal Distribution (±2 SD) SVG

Chloroplast Structure

Chloroplast Structure SVG

Photosynthesis Overview

Photosynthesis Overview SVG

Light Dependent Reaction

Light Dependent Reaction SVG

Photolysis

Photolysis SVG

ATP Synthesis (Photosynthesis)

ATP Synthesis (Photosynthesis) SVG

NADPH Formation

NADPH Formation SVG

Cyclic Photophosphorylation

Cyclic Photophosphorylation SVG

Calvin Cycle - Carbon Fixation

Calvin Cycle - Carbon Fixation SVG

Calvin Cycle - Reduction

Calvin Cycle - Reduction SVG

Calvin Cycle - Regeneration

Calvin Cycle - Regeneration SVG

Light Intensity Graph

Light Intensity Graph SVG

CO2 Concentration Graph

CO2 Concentration Graph SVG

Temperature Graph

Temperature Graph SVG

Reduction of GP to Triose Phosphate

Reduction of GP to Triose Phosphate SVG

Chromatography

Chromatography SVG

Absorption Spectrum

Absorption Spectrum SVG

DCPIP Experiment

DCPIP Experiment SVG

Respiration Overview

Respiration Overview SVG

Glycolysis

Glycolysis SVG

Link Reaction

Link Reaction SVG

Krebs Cycle

Krebs Cycle SVG

Oxidative Phosphorylation - Hydrogen Carriers

Oxidative Phosphorylation - Hydrogen Carriers SVG

Oxidative Phosphorylation - Electron Transport Chain

Oxidative Phosphorylation - Electron Transport Chain SVG

Oxidative Phosphorylation - Chemiosmosis

Oxidative Phosphorylation - Chemiosmosis SVG

Oxidative Phosphorylation - Oxygen Final Acceptor

Oxidative Phosphorylation - Oxygen Final Acceptor SVG

Anaerobic Respiration Overview

Anaerobic Respiration Overview SVG

Anaerobic Respiration - Fermentation

Anaerobic Respiration - Fermentation SVG

Full Glycolysis Pathway

Full Glycolysis Pathway PNG

Substrate-Level Phosphorylation

Substrate-Level Phosphorylation SVG

Chemiosmosis

Chemiosmosis SVG

Oxygen as the Final Electron Acceptor

Oxygen as the Final Electron Acceptor SVG

Energy Transfer Overview

Energy Transfer Overview SVG

Energy - GPP & NPP

Energy - GPP & NPP SVG

Energy - Consumer Net Production

Energy - Consumer Net Production SVG

Nitrogen Cycle Overview

Nitrogen Cycle Overview SVG

Nitrogen Fixation

Nitrogen Fixation SVG

Ammonification

Ammonification SVG

Nitrification

Nitrification SVG

Denitrification

Denitrification SVG

Phosphorus Cycle

Phosphorus Cycle SVG

Eutrophication

Eutrophication SVG

Neurone Structure

Neurone Structure SVG

Resting Potential

Resting Potential SVG

Resting to Action Potential

Resting to Action Potential SVG

Depolarisation

Depolarisation SVG

Repolarisation

Repolarisation SVG

Myelin & Saltatory Conduction

Myelin & Saltatory Conduction SVG

Nerve Impulse Animation VIDEO

Watch on YouTube

Action Potential: Stimulus

Action Potential: Stimulus SVG

Action Potential: Hyperpolarisation

Action Potential: Hyperpolarisation SVG

$Absolute and Relative Refractory Periods$

Absolute and Relative Refractory Periods SVG

$Refractory Period$

Refractory Period SVG

Wave of Depolarisation

Wave of Depolarisation SVG

All-or-Nothing Principle

All-or-Nothing Principle SVG

Synapse Structure

Synapse Structure SVG

Synaptic Transmission Animation VIDEO

Watch on YouTube

Spatial Summation

Spatial Summation SVG

Temporal Summation

Temporal Summation SVG

Synapse Animation VIDEO

Watch on YouTube

Sarcomere VIDEO

Watch on YouTube

Sliding Filament Theory VIDEO

Watch on YouTube

Upper Arm Muscles VIDEO

Watch on YouTube

Muscle Fascicles and Fibres

Muscle Fascicles and Fibres PNG

Myofibrils and Sarcomeres

Myofibrils and Sarcomeres PNG

Kidney Structure

Kidney Structure SVG

Nephron Structure

Nephron Structure SVG

Ultrafiltration

Ultrafiltration SVG

Glomerular Capillary Wall

Glomerular Capillary Wall SVG

Proteins Remain in Blood

Proteins Remain in Blood SVG

PCT Overview

PCT Overview SVG

PCT Adaptations

PCT Adaptations SVG

PCT - Active Transport

PCT - Active Transport SVG

PCT - Co-transport

PCT - Co-transport SVG

PCT - Facilitated Diffusion & Osmosis

PCT - Facilitated Diffusion & Osmosis SVG

Loop of Henle Structure

Loop of Henle Structure SVG

Loop of Henle - Na+ Transport

Loop of Henle - Na+ Transport SVG

Loop of Henle - Water Movement

Loop of Henle - Water Movement SVG

Loop of Henle - Concentration Gradient

Loop of Henle - Concentration Gradient SVG

Loop of Henle - Na+ Diffusion

Loop of Henle - Na+ Diffusion SVG

DCT & Collecting Duct - Water Reabsorption

DCT & Collecting Duct - Water Reabsorption SVG

ADH - Osmoreceptors & Hypothalamus

ADH - Osmoreceptors & Hypothalamus SVG

ADH - Aquaporins & Permeability

ADH - Aquaporins & Permeability SVG

Kidney Osmoregulation Summary

Kidney Osmoregulation Summary SVG

Insulin and Glucose Uptake

Insulin and Glucose Uptake SVG

Glucagon (Alpha Cells)

Glucagon (Alpha Cells) SVG

Second Messenger Model (cAMP)

Second Messenger Model (cAMP) SVG

Islets of Langerhans

Islets of Langerhans PNG

Genotypes TT, Tt and tt

Genotypes TT, Tt and tt SVG

A Cross: Meiosis and Fertilisation

A Cross: Meiosis and Fertilisation SVG

Punnett Square (Tt × Tt)

Punnett Square (Tt × Tt) SVG

The 23 Pairs of Chromosomes

The 23 Pairs of Chromosomes SVG

Sex-Linked Carrier Female and Affected Male

Sex-Linked Carrier Female and Affected Male SVG

Pedigree Diagram

Pedigree Diagram SVG

Pedigree: Polydactyly

Pedigree: Polydactyly SVG

Autosomal Linkage

Autosomal Linkage SVG

Recessive Epistasis (Mice)

Recessive Epistasis (Mice) SVG

Dominant Epistasis (Squash)

Dominant Epistasis (Squash) SVG

Gene Pool and Allele Frequency

Gene Pool and Allele Frequency SVG

Natural Selection

Natural Selection SVG

Types of Selection

Types of Selection SVG

Genetic Drift

Genetic Drift SVG

Allopatric and Sympatric Speciation

Allopatric and Sympatric Speciation SVG

Levels of Organisation

Levels of Organisation SVG

Habitat and Niche

Habitat and Niche SVG

Carrying Capacity

Carrying Capacity SVG

Predator–Prey Cycles

Predator–Prey Cycles SVG

Log Scale: Each Step ×10

Log Scale: Each Step ×10 SVG

Growth Curve on a Log Scale

Growth Curve on a Log Scale SVG

Reading Values from a Log Scale

Reading Values from a Log Scale SVG

Random Quadrats

Random Quadrats SVG

Belt Transect

Belt Transect SVG

Mark-Release-Recapture

Mark-Release-Recapture SVG

Primary Succession

Primary Succession SVG

Gene Expression Overview

Gene Expression Overview SVG

Gene Technology Overview

Gene Technology Overview SVG

Addition Mutation VIDEO

Watch on YouTube

Deletion Mutation VIDEO

Watch on YouTube

Substitution Mutation VIDEO

Watch on YouTube

Duplication Mutation VIDEO

Watch on YouTube

Inversion Mutation VIDEO

Watch on YouTube

Translocation Mutation VIDEO

Watch on YouTube

Gene Mutations

Gene Mutations SVG

Stem Cell

Stem Cell SVG

RNA Interference

RNA Interference SVG

Methylation

Methylation SVG

Acetylation

Acetylation SVG

Deacetylation

Deacetylation SVG

Gene Regulation Overview

Gene Regulation Overview SVG

Epigenetics Overview

Epigenetics Overview SVG

Oestrogen Receptor

Oestrogen Receptor SVG

Epigenetic Marks

Epigenetic Marks SVG

Tumour Suppressor / Oncogene

Tumour Suppressor / Oncogene SVG

Tumour / Cancer 2

Tumour / Cancer 2 SVG

Proto-oncogene

Proto-oncogene SVG

Proto-oncogene 2

Proto-oncogene 2 SVG

Eukaryotic Cell

Eukaryotic Cell SVG

Proteome

Proteome SVG

PCR

PCR SVG

Recombinant DNA - In Vivo

Recombinant DNA - In Vivo SVG

Recombinant DNA - In Vivo 2

Recombinant DNA - In Vivo 2 SVG

Gene Machine

Gene Machine SVG

Reverse Transcriptase

Reverse Transcriptase SVG

PCR

PCR SVG

DNA Probe

DNA Probe SVG

Crime Scene (Genetic Fingerprinting)

Crime Scene (Genetic Fingerprinting) SVG

VNTRs

VNTRs SVG