• International
  • Schools directory
  • Resources Jobs Schools directory News Search

The importance of receptors in living organism-A*/A A LEVEL BIOLOGY ESSAY

The importance of receptors in living organism-A*/A A LEVEL BIOLOGY ESSAY

Subject: Biology

Age range: 16+

Resource type: Unit of work

tvishah18

Last updated

22 June 2020

  • Share through email
  • Share through twitter
  • Share through linkedin
  • Share through facebook
  • Share through pinterest

aqa a level biology receptors essay

AQA A LEVEL A*/A MODEL BIOLOGY ESSAY

Tes paid licence How can I reuse this?

Your rating is required to reflect your happiness.

It's good to leave some feedback.

Something went wrong, please try again later.

This resource hasn't been reviewed yet

To ensure quality for our reviews, only customers who have purchased this resource can review it

Report this resource to let us know if it violates our terms and conditions. Our customer service team will review your report and will be in touch.

Not quite what you were looking for? Search by keyword to find the right resource:

Receptors have two important features:

Illustrative background for Specificity

Specificity

  • Temperature.
  • This means that a receptor that responds to light will not respond to temperature or pressure.

Illustrative background for Generator potentials

Generator potentials

  • Receptors connect with sensory neurones. When stimulated, the receptor creates a generator potential in the sensory neurone.
  • An example where stimulation of the receptor creates a generator potential is in the Pacinian corpuscle.

The Pacinian Corpuscle

The Pacinian corpuscle is a mechanoreceptor found in the skin. Mechanoreceptors respond to changes in pressure to establish a generator potential. The receptor reacts in the following way:

Illustrative background for Resting potential

Resting potential

  • The Pacinian corpuscle consists of concentric rings of connective tissue that surround a sensory neurone.
  • When the corpuscle is not being stimulated it is at resting state.
  • At resting state, the charge inside the neurone is more negative than outside (-70mV). This is because there are more Na + ions outside the neurone than inside.
  • A difference in charge across the cell membrane is called the potential difference.

Illustrative background for Stimulation of the receptor

Stimulation of the receptor

  • When pressure is applied to the Pacinian corpuscle, the rings of connective tissue apply pressure on the sensory neurone.
  • The sensory neurone has stretch mediated Na + channels, these channels normally restrict the movement of Na + ions.
  • Applied pressure causes the stretch-mediated Na + channels to open.

Illustrative background for Generator potential

Generator potential

  • Na + ions flood into the sensory neurone through the open Na + channels.
  • There are now more Na + ions inside the neurone than outside.
  • The charge inside the neurone becomes more positive than outside, so the potential difference has changed.
  • The generator potential has been established.

Illustrative background for Action potential

Action potential

  • If the generator potential reaches the threshold level (about -50mV) then an action potential is produced in the sensory neurone.

1 Biological Molecules

1.1 Monomers & Polymers

1.1.1 Monomers & Polymers

1.1.2 Condensation & Hydrolysis Reactions

1.2 Carbohydrates

1.2.1 Structure of Carbohydrates

1.2.2 Types of Polysaccharides

1.2.3 End of Topic Test - Monomers, Polymers and Carbs

1.2.4 Exam-Style Question - Carbohydrates

1.2.5 A-A* (AO3/4) - Carbohydrates

1.3.1 Triglycerides & Phospholipids

1.3.2 Types of Fatty Acids

1.3.3 Testing for Lipids

1.3.4 Exam-Style Question - Fats

1.3.5 A-A* (AO3/4) - Lipids

1.4 Proteins

1.4.1 The Peptide Chain

1.4.2 Investigating Proteins

1.4.3 Primary & Secondary Protein Structure

1.4.4 Tertiary & Quaternary Protein Structure

1.4.5 Enzymes

1.4.6 Factors Affecting Enzyme Activity

1.4.7 Enzyme-Controlled Reactions

1.4.8 End of Topic Test - Lipids & Proteins

1.4.9 A-A* (AO3/4) - Enzymes

1.4.10 A-A* (AO3/4) - Proteins

1.5 Nucleic Acids

1.5.1 DNA & RNA

1.5.2 Polynucleotides

1.5.3 DNA Replication

1.5.4 Exam-Style Question - Nucleic Acids

1.5.5 A-A* (AO3/4) - Nucleic Acids

1.6.1 Structure of ATP

1.6.2 End of Topic Test - Nucleic Acids & ATP

1.7.1 Structure & Function of Water

1.7.2 A-A* (AO3/4) - Water

1.8 Inorganic Ions

1.8.1 Inorganic Ions

1.8.2 End of Topic Test - Water & Inorganic Ions

2.1 Cell Structure

2.1.1 Introduction to Cells

2.1.2 Eukaryotic Cells & Organelles

2.1.3 Eukaryotic Cells & Organelles 2

2.1.4 Prokaryotes

2.1.5 A-A* (AO3/4) - Organelles

2.1.6 Methods of Studying Cells

2.1.7 Microscopes

2.1.8 End of Topic Test - Cell Structure

2.1.9 Exam-Style Question - Cells

2.1.10 A-A* (AO3/4) - Cells

2.2 Mitosis & Cancer

2.2.1 Mitosis

2.2.2 Investigating Mitosis

2.2.3 Cancer

2.2.4 A-A* (AO3/4) - The Cell Cycle

2.3 Transport Across Cell Membrane

2.3.1 Cell Membrane Structure

2.3.2 A-A* (AO3/4) - Membrane Structure

2.3.3 Diffusion

2.3.4 Osmosis

2.3.5 Active Transport

2.3.6 End of Topic Test - Mitosis, Cancer & Transport

2.3.7 Exam-Style Question - Membranes

2.3.8 A-A* (AO3/4) - Membranes & Transport

2.3.9 A-A*- Mitosis, Cancer & Transport

2.4 Cell Recognition & the Immune System

2.4.1 Immune System

2.4.2 The Immune Response

2.4.3 Antibodies

2.4.4 Primary & Secondary Response

2.4.5 Vaccines

2.4.7 Ethical Issues

2.4.8 End of Topic Test - Immune System

2.4.9 Exam-Style Question - Immune System

2.4.10 A-A* (AO3/4) - Immune System

3 Substance Exchange

3.1 Surface Area to Volume Ratio

3.1.1 Size & Surface Area

3.1.2 A-A* (AO3/4) - Cell Size

3.2 Gas Exchange

3.2.1 Single-Celled Organisms

3.2.2 Multicellular Organisms

3.2.3 Control of Water Loss

3.2.4 Human Gas Exchange

3.2.5 Ventilation

3.2.6 Dissection

3.2.7 Measuring Gas Exchange

3.2.8 Lung Disease

3.2.9 Lung Disease Data

3.2.10 End of Topic Test - Gas Exchange

3.2.11 A-A* (AO3/4) - Gas Exchange

3.3 Digestion & Absorption

3.3.1 Overview of Digestion

3.3.2 Digestion in Mammals

3.3.3 Absorption

3.3.4 End of Topic Test - Substance Exchange & Digestion

3.3.5 A-A* (AO3/4) - Substance Ex & Digestion

3.4 Mass Transport

3.4.1 Haemoglobin

3.4.2 Oxygen Transport

3.4.3 The Circulatory System

3.4.4 The Heart

3.4.5 Blood Vessels

3.4.6 Cardiovascular Disease

3.4.7 Heart Dissection

3.4.8 Xylem

3.4.9 Phloem

3.4.10 Investigating Plant Transport

3.4.11 End of Topic Test - Mass Transport

3.4.12 A-A* (AO3/4) - Mass Transport

4 Genetic Information & Variation

4.1 DNA, Genes & Chromosomes

4.1.2 Genes

4.1.3 A-A* (AO3/4) - DNA

4.2 DNA & Protein Synthesis

4.2.1 Protein Synthesis

4.2.2 Transcription & Translation

4.2.3 End of Topic Test - DNA, Genes & Protein Synthesis

4.2.4 Exam-Style Question - Protein Synthesis

4.2.5 A-A* (AO3/4) - Coronavirus Translation

4.2.6 A-A* (AO3/4) - Transcription

4.2.7 A-A* (AO3/4) - Translation

4.3 Mutations & Meiosis

4.3.1 Mutations

4.3.2 Meiosis

4.3.3 A-A* (AO3/4) - Meiosis

4.3.4 Meiosis vs Mitosis

4.3.5 End of Topic Test - Mutations, Meiosis

4.3.6 A-A* (AO3/4) - DNA,Genes, CellDiv & ProtSynth

4.4 Genetic Diversity & Adaptation

4.4.1 Genetic Diversity

4.4.2 Natural Selection

4.4.3 A-A* (AO3/4) - Natural Selection

4.4.4 Adaptations

4.4.5 Investigating Natural Selection

4.4.6 End of Topic Test - Genetic Diversity & Adaptation

4.4.7 A-A* (AO3/4) - Genetic Diversity & Adaptation

4.5 Species & Taxonomy

4.5.1 Classification

4.5.2 DNA Technology

4.5.3 A-A* (AO3/4) - Species & Taxonomy

4.6 Biodiversity Within a Community

4.6.1 Biodiversity

4.6.2 Agriculture

4.6.3 End of Topic Test - Species,Taxonomy& Biodiversity

4.6.4 A-A* (AO3/4) - Species,Taxon&Biodiversity

4.7 Investigating Diversity

4.7.1 Genetic Diversity

4.7.2 Quantitative Investigation

5 Energy Transfers (A2 only)

5.1 Photosynthesis

5.1.1 Overview of Photosynthesis

5.1.2 Light-Dependent Reaction

5.1.3 Light-Independent Reaction

5.1.4 A-A* (AO3/4) - Photosynthesis Reactions

5.1.5 Limiting Factors

5.1.6 Photosynthesis Experiments

5.1.7 End of Topic Test - Photosynthesis

5.1.8 A-A* (AO3/4) - Photosynthesis

5.2 Respiration

5.2.1 Overview of Respiration

5.2.2 Anaerobic Respiration

5.2.3 A-A* (AO3/4) - Anaerobic Respiration

5.2.4 Aerobic Respiration

5.2.5 Respiration Experiments

5.2.6 End of Topic Test - Respiration

5.2.7 A-A* (AO3/4) - Respiration

5.3 Energy & Ecosystems

5.3.1 Biomass

5.3.2 Production & Productivity

5.3.3 Agricultural Practices

5.4 Nutrient Cycles

5.4.1 Nitrogen Cycle

5.4.2 Phosphorous Cycle

5.4.3 Fertilisers & Eutrophication

5.4.4 End of Topic Test - Nutrient Cycles

5.4.5 A-A* (AO3/4) - Energy,Ecosystems&NutrientCycles

6 Responding to Change (A2 only)

6.1 Nervous Communication

6.1.1 Survival

6.1.2 Plant Responses

6.1.3 Animal Responses

6.1.4 Reflexes

6.1.5 End of Topic Test - Reflexes, Responses & Survival

6.1.6 Receptors

6.1.7 The Human Retina

6.1.8 Control of Heart Rate

6.1.9 End of Topic Test - Receptors, Retina & Heart Rate

6.2 Nervous Coordination

6.2.1 Neurones

6.2.2 Action Potentials

6.2.3 Speed of Transmission

6.2.4 End of Topic Test - Neurones & Action Potentials

6.2.5 Synapses

6.2.6 Types of Synapse

6.2.7 Medical Application

6.2.8 End of Topic Test - Synapses

6.2.9 A-A* (AO3/4) - Nervous Comm&Coord

6.3 Muscle Contraction

6.3.1 Skeletal Muscle

6.3.2 Sliding Filament Theory

6.3.3 Contraction

6.3.4 Slow & Fast Twitch Fibres

6.3.5 End of Topic Test - Muscles

6.3.6 A-A* (AO3/4) - Muscle Contraction

6.4 Homeostasis

6.4.1 Overview of Homeostasis

6.4.2 Blood Glucose Concentration

6.4.3 Controlling Blood Glucose Concentration

6.4.4 End of Topic Test - Blood Glucose

6.4.5 Primary & Secondary Messengers

6.4.6 Diabetes Mellitus

6.4.7 Measuring Glucose Concentration

6.4.8 Osmoregulation

6.4.9 Controlling Blood Water Potential

6.4.11 End of Topic Test - Diabetes & Osmoregulation

6.4.12 A-A* (AO3/4) - Homeostasis

7 Genetics & Ecosystems (A2 only)

7.1 Genetics

7.1.1 Key Terms in Genetics

7.1.2 Inheritance

7.1.3 Linkage

7.1.4 Multiple Alleles & Epistasis

7.1.5 Chi-Squared Test

7.1.6 End of Topic Test - Genetics

7.1.7 A-A* (AO3/4) - Genetics

7.2 Populations

7.2.1 Populations

7.2.2 Hardy-Weinberg Principle

7.3 Evolution

7.3.1 Variation

7.3.2 Natural Selection & Evolution

7.3.3 End of Topic Test - Populations & Evolution

7.3.4 Types of Selection

7.3.5 Types of Selection Summary

7.3.6 Overview of Speciation

7.3.7 Causes of Speciation

7.3.8 Diversity

7.3.9 End of Topic Test - Selection & Speciation

7.3.10 A-A* (AO3/4) - Populations & Evolution

7.4 Populations in Ecosystems

7.4.1 Overview of Ecosystems

7.4.2 Niche

7.4.3 Population Size

7.4.4 Investigating Population Size

7.4.5 End of Topic Test - Ecosystems & Population Size

7.4.6 Succession

7.4.7 Conservation

7.4.8 End of Topic Test - Succession & Conservation

7.4.9 A-A* (AO3/4) - Ecosystems

8 The Control of Gene Expression (A2 only)

8.1 Mutation

8.1.1 Mutations

8.1.2 Effects of Mutations

8.1.3 Causes of Mutations

8.2 Gene Expression

8.2.1 Stem Cells

8.2.2 Stem Cells in Disease

8.2.3 End of Topic Test - Mutation & Gene Epression

8.2.4 A-A* (AO3/4) - Mutation & Stem Cells

8.2.5 Regulating Transcription

8.2.6 Epigenetics

8.2.7 Epigenetics & Disease

8.2.8 Regulating Translation

8.2.9 Experimental Data

8.2.10 End of Topic Test - Transcription & Translation

8.2.11 Tumours

8.2.12 Correlations & Causes

8.2.13 Prevention & Treatment

8.2.14 End of Topic Test - Cancer

8.2.15 A-A* (AO3/4) - Gene Expression & Cancer

8.3 Genome Projects

8.3.1 Using Genome Projects

8.4 Gene Technology

8.4.1 Recombinant DNA

8.4.2 Producing Fragments

8.4.3 Amplification

8.4.4 End of Topic Test - Genome Project & Amplification

8.4.5 Using Recombinant DNA

8.4.6 Medical Diagnosis

8.4.7 Genetic Fingerprinting

8.4.8 End of Topic Test - Gene Technologies

8.4.9 A-A* (AO3/4) - Gene Technology

Jump to other topics

Go student ad image

Unlock your full potential with GoStudent tutoring

Affordable 1:1 tutoring from the comfort of your home

Tutors are matched to your specific learning needs

30+ school subjects covered

End of Topic Test - Reflexes, Responses & Survival

The Human Retina

We are sorry Physics & Maths Tutor is slow. There's so many of you visiting at the same time, it's struggling. We are releasing an update later this week.

PMT

Topic 6 – Organisms Respond to Changes in Environments

Bailey 's Profile Picture

Bailey L. ★ 5.0 (2)

Univeristy of leicester - mbchb medicine.

Experienced A-level Biology and Chemistry tutor, expert in medical entrance exams, personal statments and interviews

PMT Education

Notes || Questions by Topic

  • Definitions
  • Summary Notes
  • 6.1 Internal and external stimuli are detected and lead to a response
  • 6.2 Nervous coordination
  • 6.3 Skeletal muscles
  • 6.4 Homeostasis is the maintenance of a stable internal environment
  • 6.1 Internal and External Stimuli
  • 6.2 Nervous Coordination
  • 6.3 Skeletal Muscle
  • 6.4 Homeostasis

Questions by Topic

2016-2021 papers.

  • 6.1 Control of Heart Rate MS
  • 6.1 Control of Heart Rate QP
  • 6.1 Receptors MS
  • 6.1 Receptors QP
  • 6.1 Survival and Response MS
  • 6.1 Survival and Response QP
  • 6.2 Nervous Coordination MS
  • 6.2 Nervous Coordination QP
  • 6.3 Contraction of Skeletal Muscles MS
  • 6.3 Contraction of Skeletal Muscles QP
  • 6.4 Control of blood glucose concentration MS
  • 6.4 Control of blood glucose concentration QP
  • 6.4 Control of blood water potential MS
  • 6.4 Control of blood water potential QP
  • 6.4 Homeostasis MS
  • 6.4 Homeostasis QP

pre-2016 papers

  • 6.2 Nerve Impulses MS
  • 6.2 Nerve Impulses QP
  • 6.2 Synaptic Transmission MS
  • 6.2 Synaptic Transmission QP
  • 6.3 Skeletal Muscles MS
  • 6.3 Skeletal Muscles QP
  • 6.4 Control of Blood Glucose MS
  • 6.4 Control of Blood Glucose QP
  • 6.4 Osmoregulation MS
  • 6.4 Osmoregulation QP
  • 6.4 Principles of Homeostasis and Negative Feedback MS
  • 6.4 Principles of Homeostasis and Negative Feedback QP

Connect with PMT Education!

  • Revision Courses
  • Past Papers
  • Solution Banks
  • University Admissions
  • Numerical Reasoning
  • Legal Notices

A Level Biology

Instant Access to A Level Biology Revision

Sign up now to get access to the entire library of a level biology resources for all exam boards.

Study Mind logo

Book a free consultation now

100+ Video Tutorials, Flashcards and Weekly Seminars

  • Revision notes >
  • A-Level Biology >
  • CIE A-level Biology

Photoreceptors (A-level Biology)

Photoreceptors, light receptors in the eye.

Receptors , which are specialised cells, help to make up the sense organs to detect stimuli.

The retinas of the eye contain photoreceptors that detect light. They contain different light-sensitive optical pigments, so they are sensitive to different wavelengths of light.

There are two types of photoreceptors in the retina: cones and rods .

Light rays enter through the pupil and are focused onto the retina by the lens.

The photoreceptors in the retina produce impulses that travel through the optic nerve to the brain.

Conversion of Light into Electrical Impulses

  • The light is absorbed by light-sensitive optical pigments in the photoreceptors .
  • This causes a chemical change that increases the permeability of the membrane to Na+ ions.
  • Na+ ions rush into the membrane. This stimulates a generator potential, which sends the impulse along a bipolar nerve to the brain.

Cone cells are located in the centre of the retina in an area called the fovea . There are around 6 million of these cells which help to produce the clearest image possible.

  • Cone cells give information in colour . There are three types: red -sensitive receptors, green -sensitive receptors and blue -sensitive receptors. Different intensities of light in these pigments allow for colour to be seen.
  • Cone cells only detect high light intensity . This is because each cone   cell connects to only one neurone , so it takes higher intensities of light to trigger a generator potential.
  • They have high visual acuity . Visual acuity is the ability to tell apart two points that are close together. Cone cells only connect to one other neurone, so each individual stimuli can be distinguished.

A-level Biology - Photoreceptors

Rod cells are located in the periphery of the retina (the outer region), giving peripheral vision, and are more abundant than cone cells, approximating 120 million cells.

  • Rod cells absorb light energy . A light-sensitive pigment, rhodopsin , in contained in rod cells. It absorbs light energy to split into cis-retinal and cis-opsin, in a process known as bleaching .
  • Rod cells are monochromatic . This means that they only give information in black and white.
  • Rod cells can detect both high and low light intensity . This is because three rod cells are connected to one bipolar cell , so many weaker signals can combine to trigger a generator potential.
  • Rod cells have low visual acuity . Many rod cells are connected to one neurone , which means the stimuli merge together, making points harder to differentiate.

A-level Biology - Photoreceptors

How Rod Cells Work

  • The membrane is depolarised . Active transport pumps sodium ions through open sodium ion channels, making the cell slightly more negative on the inside, causing a depolarisation .
  • Glutamate in rod cells stop information being passed to the brain . Glutamate , a neurotransmitter, stops neurones connecting the rod cells to the optic nerve (creating an ISPS), inhibiting information reaching the brain.
  • The membrane becomes hyper-polarised . After bleaching, the sodium ion channels close, not affecting the active transport of sodium ions, as cis-opsin binds to the membranes.
  • An action potential forms . The neurotransmitter isn’t released into the synaptic cleft creating an action potential, getting transported to the brain through the optic nerve.

The table below gives an overview of where the photoreceptors are located and what their function is.

A-level Biology - Photoreceptors

Photoreceptors are specialized cells in the eye that detect light and convert it into neural signals that can be processed by the brain.

The two types of photoreceptors in the eye are rods and cones.

Rods are specialized photoreceptors that are sensitive to low levels of light and are responsible for night vision. Cones, on the other hand, are specialized photoreceptors that are responsible for color vision and visual acuity in bright light.

Photoreceptors work by absorbing photons of light and triggering chemical and electrical changes in the cell, which then triggers a nerve impulse that is sent to the brain.

The process by which photoreceptors convert light into a neural signal is known as phototransduction. This process involves the activation of a photopigment in the photoreceptor, which triggers a cascade of chemical reactions that result in the release of a neurotransmitter.

The neurotransmitter plays a critical role in phototransduction as it helps to transmit the neural signal from the photoreceptor to the bipolar cells in the retina, which then pass the signal on to the ganglion cells and eventually to the brain.

When there is too much light in the eye, it can cause the photoreceptors to become overstimulated, leading to visual discomfort and even temporary vision loss in extreme cases.

The pigment epithelium is a layer of cells in the eye that helps to support and protect the photoreceptors, as well as to recycle the photopigments that are used in phototransduction.

Photoreceptor cells are replenished through a process known as neurogenesis, where new photoreceptor cells are generated from stem cells in the retina.

Some disorders related to photoreceptors include age-related macular degeneration, retinitis pigmentosa, and night blindness. These conditions can result in a loss of visual function and can ultimately lead to vision loss if left untreated.

Still got a question? Leave a comment

Leave a comment, cancel reply.

Save my name, email, and website in this browser for the next time I comment.

CIE 1 Cell structure

Roles of atp (a-level biology), atp as an energy source (a-level biology), the synthesis and hydrolysis of atp (a-level biology), the structure of atp (a-level biology), magnification and resolution (a-level biology), calculating cell size (a-level biology), studying cells: confocal microscopes (a-level biology), studying cells: electron microscopes (a-level biology), studying cells: light microscopes (a-level biology), life cycle and replication of viruses (a-level biology), cie 10 infectious disease, bacteria, antibiotics, and other medicines (a-level biology), pathogens and infectious diseases (a-level biology), cie 11 immunity, types of immunity and vaccinations (a-level biology), structure and function of antibodies (a-level biology), the adaptive immune response (a-level biology), introduction to the immune system (a-level biology), primary defences against pathogens (a-level biology), cie 12 energy and respiration, anaerobic respiration in mammals, plants and fungi (a-level biology), anaerobic respiration (a-level biology), oxidative phosphorylation and chemiosmosis (a-level biology), oxidative phosphorylation and the electron transport chain (a-level biology), the krebs cycle (a-level biology), the link reaction (a-level biology), the stages and products of glycolysis (a-level biology), glycolysis (a-level biology), the structure of mitochondria (a-level biology), the need for cellular respiration (a-level biology), cie 13 photosynthesis, limiting factors of photosynthesis (a-level biology), cyclic and non-cyclic phosphorylation (a-level biology), the 2 stages of photosynthesis (a-level biology), photosystems and photosynthetic pigments (a-level biology), site of photosynthesis, overview of photosynthesis (a-level biology), cie 14 homeostasis, ectotherms and endotherms (a-level biology), thermoregulation (a-level biology), plant responses to changes in the environment (a-level biology), cie 15 control and co-ordination, the nervous system (a-level biology), sources of atp during contraction (a-level biology), the ultrastructure of the sarcomere during contraction (a-level biology), the role of troponin and tropomyosin (a-level biology), the structure of myofibrils (a-level biology), slow and fast twitch muscles (a-level biology), the structure of mammalian muscles (a-level biology), how muscles allow movement (a-level biology), the neuromuscular junction (a-level biology), features of synapses (a-level biology), cie 16 inherited change, calculating genetic diversity (a-level biology), how meiosis produces variation (a-level biology), cell division by meiosis (a-level biology), importance of meiosis (a-level biology), cie 17 selection and evolution, types of selection (a-level biology), mechanism of natural selection (a-level biology), types of variation (a-level biology), cie 18 biodiversity, classification and conservation, biodiversity and gene technology (a-level biology), factors affecting biodiversity (a-level biology), biodiversity calculations (a-level biology), introducing biodiversity (a-level biology), the three domain system (a-level biology), phylogeny and classification (a-level biology), classifying organisms (a-level biology), cie 19 genetic technology, cie 2 biological molecules, properties of water (a-level biology), structure of water (a-level biology), test for lipids and proteins (a-level biology), tests for carbohydrates (a-level biology), protein structures: globular and fibrous proteins (a-level biology), protein structures: tertiary and quaternary structures (a-level biology), protein structures: primary and secondary structures (a-level biology), protein formation (a-level biology), proteins and amino acids: an introduction (a-level biology), phospholipid bilayer (a-level biology), cie 3 enzymes, enzymes: inhibitors (a-level biology), enzymes: rates of reaction (a-level biology), enzymes: intracellular and extracellular forms (a-level biology), enzymes: mechanism of action (a-level biology), enzymes: key concepts (a-level biology), enzymes: introduction (a-level biology), cie 4 cell membranes and transport, transport across membranes: active transport (a-level biology), investigating transport across membranes (a-level biology), transport across membranes: osmosis (a-level biology), transport across membranes: diffusion (a-level biology), signalling across cell membranes (a-level biology), function of cell membrane (a-level biology), factors affecting cell membrane structure (a-level biology), structure of cell membranes (a-level biology), cie 5 the mitotic cell cycle, chromosome mutations (a-level biology), cell division: checkpoints and mutations (a-level biology), cell division: phases of mitosis (a-level biology), cell division: the cell cycle (a-level biology), cell division: chromosomes (a-level biology), cie 6 nucleic acids and protein synthesis, transfer rna (a-level biology), transcription (a-level biology), messenger rna (a-level biology), introducing the genetic code (a-level biology), genes and protein synthesis (a-level biology), synthesising proteins from dna (a-level biology), structure of rna (a-level biology), dna replication (a-level biology), dna structure and the double helix (a-level biology), polynucleotides (a-level biology), cie 7 transport in plants, translocation and evidence of the mass flow hypothesis (a-level biology), the phloem (a-level biology), importance of and evidence for transpiration (a-level biology), introduction to transpiration (a-level biology), the pathway and movement of water into the roots and xylem (a-level biology), the xylem (a-level biology), cie 8 transport in mammals, controlling heart rate (a-level biology), structure of the heart (a-level biology), transport of carbon dioxide (a-level biology), transport of oxygen (a-level biology), exchange in capillaries (a-level biology), structure and function of blood vessels (a-level biology), cie 9 gas exchange and smoking, lung disease (a-level biology), pulmonary ventilation rate (a-level biology), ventilation (a-level biology), structure of the lungs (a-level biology), general features of exchange surfaces (a-level biology), understanding surface area to volume ratio (a-level biology), the need for exchange surfaces (a-level biology), edexcel a 1: lifestyle, health and risk, phospholipids – introduction (a-level biology), edexcel a 2: genes and health, features of the genetic code (a-level biology), gas exchange in plants (a-level biology), gas exchange in insects (a-level biology), edexcel a 3: voice of the genome, edexcel a 4: biodiversity and natural resources, edexcel a 5: on the wild side, reducing biomass loss (a-level biology), sources of biomass loss (a-level biology), transfer of biomass (a-level biology), measuring biomass (a-level biology), net primary production (a-level biology), gross primary production (a-level biology), trophic levels (a-level biology), edexcel a 6: immunity, infection & forensics, microbial techniques (a-level biology), the innate immune response (a-level biology), edexcel a 7: run for your life, edexcel a 8: grey matter, inhibitory synapses (a-level biology), synaptic transmission (a-level biology), the structure of the synapse (a-level biology), factors affecting the speed of transmission (a-level biology), myelination (a-level biology), the refractory period (a-level biology), all or nothing principle (a-level biology), edexcel b 1: biological molecules, inorganic ions (a-level biology), edexcel b 10: ecosystems, nitrogen cycle: nitrification and denitrification (a-level biology), the phosphorus cycle (a-level biology), nitrogen cycle: fixation and ammonification (a-level biology), introduction to nutrient cycles (a-level biology), edexcel b 2: cells, viruses, reproduction, edexcel b 3: classification & biodiversity, edexcel b 4: exchange and transport, edexcel b 5: energy for biological processes, edexcel b 6: microbiology and pathogens, edexcel b 7: modern genetics, edexcel b 8: origins of genetic variation, edexcel b 9: control systems, ocr 2.1.1 cell structure, structure of prokaryotic cells (a-level biology), eukaryotic cells: comparing plant and animal cells (a-level biology), eukaryotic cells: plant cell organelles (a-level biology), eukaryotic cells: the endoplasmic reticulum (a-level biology), eukaryotic cells: the golgi apparatus and lysosomes (a-level biology), ocr 2.1.2 biological molecules, introduction to eukaryotic cells and organelles (a-level biology), ocr 2.1.3 nucleotides and nucleic acids, ocr 2.1.4 enzymes, ocr 2.1.5 biological membranes, ocr 2.1.6 cell division, diversity & organisation, ocr 3.1.1 exchange surfaces, ocr 3.1.2 transport in animals, ocr 3.1.3 transport in plants, examples of xerophytes (a-level biology), introduction to xerophytes (a-level biology), ocr 4.1.1 communicable diseases, structure of viruses (a-level biology), ocr 4.2.1 biodiversity, ocr 4.2.2 classification and evolution, ocr 5.1.1 communication and homeostasis, the resting potential (a-level biology), ocr 5.1.2 excretion, ocr 5.1.3 neuronal communication, hyperpolarisation and transmission of the action potential (a-level biology), depolarisation and repolarisation in the action potential (a-level biology), ocr 5.1.4 hormonal communication, ocr 5.1.5 plant and animal responses, ocr 5.2.1 photosynthesis, ocr 5.2.2 respiration, ocr 6.1.1 cellular control, ocr 6.1.2 patterns of inheritance, ocr 6.1.3 manipulating genomes, ocr 6.2.1 cloning and biotechnology, ocr 6.3.1 ecosystems, ocr 6.3.2 populations and sustainability.

aqa a level biology receptors essay

Let's get acquainted ? What is your name?

Nice to meet you, {{name}} what is your preferred e-mail address, nice to meet you, {{name}} what is your preferred phone number, what is your preferred phone number, just to check, what are you interested in, when should we call you.

It would be great to have a 15m chat to discuss a personalised plan and answer any questions

What time works best for you? (UK Time)

Pick a time-slot that works best for you ?

How many hours of 1-1 tutoring are you looking for?

My whatsapp number is..., for our safeguarding policy, please confirm....

Please provide the mobile number of a guardian/parent

Which online course are you interested in?

What is your query, you can apply for a bursary by clicking this link, sure, what is your query, thank you for your response. we will aim to get back to you within 12-24 hours., lock in a 2 hour 1-1 tutoring lesson now.

If you're ready and keen to get started click the button below to book your first 2 hour 1-1 tutoring lesson with us. Connect with a tutor from a university of your choice in minutes. (Use FAST5 to get 5% Off!)

IMAGES

  1. The importance of receptors in living organism-A*/A A LEVEL BIOLOGY

    aqa a level biology receptors essay

  2. AQA A-level Biology

    aqa a level biology receptors essay

  3. Cell Recognition and The Immune System Revision Mind Map

    aqa a level biology receptors essay

  4. AQA A Level Biology Lecture 43

    aqa a level biology receptors essay

  5. AQA A Level Biology Essay

    aqa a level biology receptors essay

  6. AQA A Level Biology Essay Plans

    aqa a level biology receptors essay

VIDEO

  1. Unit 1 AP Biology Topics 1.3

  2. Biology A- Level #ocr #aqa #edexcel

  3. Receptors Biology

  4. K A prediction for AQA A-Level Biology Essay questions #alevel2023 #alevelbiology #alevels2023

  5. OCR A Level Biology Module 2 4 Enzymes: Part 1

  6. Biology Explained Pt 1 & 2

COMMENTS

  1. PDF ASE 2018 A-level Biology Essay Booklet

    Biology is detailed and comprehensive A-level content, uses appropriate terminology, and is very well written and always clearly explained. No significant errors or irrelevant material. For top marks in the band, the answer shows evidence of reading beyond specification requirements. 16-20. Relational.

  2. PDF The A-level Biology essay

    The levels scheme states that more than two A-level topics need to be addressed to get higher than 10 marks. A minimum of four topics is required to get higher than 15 marks. A topic area is a numbered sub-section in the specification. For example, for the 2017 'diffusion' essay, gas exchange (3.3.2) was a topic area.

  3. AQA A level biology essay titles and mark schemes

    44 essay titles and indiciative mark schemes for AQA A level biology Paper 3 25 mark essay question. contents essay mark schemes general guidance. Skip to document. University; High School. Books; Discovery. ... Receptors convert stimuli into electrical impulses in nerve cells [25] Q14. Inorganic ions include those of sodium, phosphorus and ...

  4. PDF Biology essay titles

    AQA Education (AQA) is a registered charity (number 1073334) and a company limited by guarantee registered in England and Wales (number 3644723). Our registered address is AQA, Devas Street, Manchester M15 6EX. Biology essay titles This document contains the essay titles and mark schemes used in AQA A-level Biology examinations since 2007.

  5. AQA A Level Biology

    The importance of shapes fitting together in cells and organisms. 1) Enzyme properties and digestion. 2) Protein structure. 3) Plasma membrane structure and cell transport. 4) Antigens, antibodies, B cells & T cells. 5) Vaccines. 6) Structure of DNA. 7) DNA Replication (not PCR) 8) Transcription & translation.

  6. The importance of receptors in living organism-A*/A A LEVEL BIOLOGY ESSAY

    The importance of receptors in living organism-A*/A A LEVEL BIOLOGY ESSAY. Subject: Biology. Age range: 16+ Resource type: Unit of work. tvishah18. 3.00 ... Share through pinterest; File previews. docx, 8.03 KB. AQA A LEVEL A*/A MODEL BIOLOGY ESSAY. Tes paid licenceHow can I reuse this? Reviews Something went wrong, please try again later. This ...

  7. The Importance of Receptors in Living Organisms_ A level biology essay

    se The Immune Response in living organisms prevents any harmful pathogens from invading precious organisms within the body. Receptors are involved in detection of harmful substances and initiate a response in a according manner. T cells are one of the major components of the immune system and rely on receptors to carry out their functions. Their roles include directly killing infected host ...

  8. Receptors

    Stimulation of the receptor. When pressure is applied to the Pacinian corpuscle, the rings of connective tissue apply pressure on the sensory neurone. The sensory neurone has stretch mediated Na + channels, these channels normally restrict the movement of Na + ions. Applied pressure causes the stretch-mediated Na + channels to open.

  9. PDF AQA Biology A-Level

    The levels mark scheme for the essay contains a number of words and statements that are open to different interpretations. This commentary defines the meanings of these words and statements in the context of marking the essay. Many words and statements are used in the AQA Biology A-Level - Receptors MS PhysicsAndMathsTutor.com

  10. AQA Biology A-level Topic 6: Organisms Respond to Changes in

    6.4 Control of Blood Glucose QP. 6.4 Osmoregulation MS. 6.4 Osmoregulation QP. 6.4 Principles of Homeostasis and Negative Feedback MS. 6.4 Principles of Homeostasis and Negative Feedback QP. Summary notes and past exam questions by topic for AQA Biology A-Level Topic 6 - Organisms Respond to Changes in Their Internal and External Environments.

  11. A LEVEL BIOLOGY: 25 Mark essays Flashcards

    Hydrogen Bonds and their importance in living organisms. •H-bonds determine shape of enzymes in tertiary structure- responsible for complementary structures. •Transpiration pull up xylem. Study with Quizlet and memorize flashcards containing terms like The importance of shapes fitting together in cells and organisms, How bacteria can affect ...

  12. Summary Biology A Level Essay: Receptors

    Extended and high scoring essay example for AQA A Level Biology on the question 'The Importance of Receptors in Biology'. ... Summary - Biology a level essay: receptors Show more . SALE - Bundle: Biology A Level Preparation. £ 14.87 £ 9.29 3 items . 1. Summary - Sale - biology a level revision questions + ...

  13. 6.2.3 Nerve Impulses

    Action potentials. There are channel proteins in the axon membrane that allow sodium ions or potassium ions to pass through; When an action potential is stimulated (eg. by a receptor cell) in a neurone, the following steps occur:; Sodium ion channels in the axon membrane open; Sodium ions pass into the axon down the electrochemical gradient (there is a greater concentration of sodium ions ...

  14. AQA A level Biology Essay Flashcards

    AQA A level Biology Essay. The importance of responses to changes in the internal and external environment of an organism. Click the card to flip 👆. Control of heart rate (changes in pH and pressure) Control of blood glucose (glucagon and insulin) Osmoregulation (water potential changes) Action potentials/ pacinian corpuscles (stimulus)

  15. Receptors

    A-level Biology focuses on providing students, tutors and teachers with detailed revision materials for A-Level Biology. Over 22,000 learners have used our materials to pass their exams. Need a tutor? Check out our partner, Spires; Stressed? Read about the Best CB D Oil for Anxiety

  16. PDF Notes and guidance: Research update: 7402 A-level biology essay

    that essays fall into being the 11-15 level, followed by the 16-20 level and the 6-10 level. The 21-25 level is the next most common mark band for essays, highlighting that it is relatively rare that an essay meets the requirements to achieve a mark over 20 on the A-level biology essay.

  17. 6.1.7 The Pacinian Corpuscle

    Pacinian corpuscles are a type of receptor found deep in the skin. They are present in the skin of fingers, soles of the feet as well as in joints, tendons and ligaments. They respond to changes in pressure. When these receptors are stimulated by pressure on the skin it leads to the establishment of a generator potential.

  18. Photoreceptors (A-level Biology)

    Photoreceptors (A-level Biology) Photoreceptors Light Receptors in the Eye. Receptors, which are specialised cells, help to make up the sense organs to detect stimuli.. The retinas of the eye contain photoreceptors that detect light. They contain different light-sensitive optical pigments, so they are sensitive to different wavelengths of light.. There are two types of photoreceptors in the ...

  19. AQA A Level Biology

    Write an essay about cycles in biology. Carbon dioxide may affect organisms directly or indirectly. Describe and explain these effects. The causes of disease in humans. 25 mark essay titles and points that can be used for them :) AQA BIOL5 Essay Titles Learn with flashcards, games, and more — for free.

  20. A level AQA-A-Level-Biology-Essay-Plans

    Biology Essay Plans. The importance of nitrogen containing substances in biological systems (25 marks) DNA: Has nitrogen containing bases- base pairing In eukaryotes, found in nucleus as histone associated chromosomes Stores genetic information and allows genetic continuity through generations Replicated semi conservatively using DNA helicase and DNA polymerase to form 2 identical molecules ...

  21. AQA A LEVEL BIOLOGY PAPER 1 2023 (7402/1)#aqa # ...

    TikTok video from BestRatedPapers (@bestratedpapers): "AQA A LEVEL BIOLOGY PAPER 1 2023 (7402/1)#aqa #aqaalevelbiology #paper1 #hackedexams". original soundBestRatedPapers.

  22. AQA A level biology essay plans Flashcards

    AQA A level biology essay plans. 1.) Na+ ions in cotransport of glucose. - importance: Na+ ion concentration gradient is what drives the movement of glucose into cell - utilising energy efficiently. 2.) Na+ ions in osmoregulation. - importance: ensures water can leave glomerular filtrate - concentrating urine - less H2O lost.

  23. 6.1.10 The Human Retina

    The Human Retina. The eye is a sense organ containing receptors sensitive to light intensity and colour. Receptors are groups of specialised cells that can generate an electrical impulse in a sensory neurone. The eye contains two types of receptor cell: Rod cells which are sensitive to light intensity.

  24. 6.2.7 Cholinergic Synapses

    Revision notes on 6.2.7 Cholinergic Synapses for the AQA A Level Biology syllabus, written by the Biology experts at Save My Exams. ... Past Papers; AQA Combined: Biology. Topic Questions; Revision Notes; Past Papers; AQA Combined: Chemistry. Topic Questions; ... 6.1.9 Investigating Touch and Temperature Receptors; 6.1.10 The Human Retina;