Bioknowledgy
questioning, investigating and understanding
  • Home
    • About
  • IB Biology
    • Syllabus
    • General Resources
    • Practical scheme of work >
      • Practical activities (Labs)
      • Individual investigation
      • IB Write
      • Group 4 project
  • Core
    • 1. Cell biology >
      • 1.1 Introduction to cells
      • 1.2 Ultrastructure of cells
      • 1.3 Membrane structure
      • 1.4 Membrane transport
      • 1.5 The origin of cells
      • 1.6 Cell division
    • 2. Molecular biology >
      • 2.1 Molecules to metabolism
      • 2.2 Water
      • 2.3 Carbohydrates and lipids
      • 2.4 Proteins
      • 2.5 Enzymes
      • 2.6 Structure of DNA and RNA
      • 2.7 DNA replication, transcription and translation
      • 2.8 Cell respiration
      • 2.9 Photosynthesis
    • 3. Genetics >
      • 3.1 Genes
      • 3.2 Chromosomes
      • 3.3 Meiosis
      • 3.4 Inheritance
      • 3.5 Genetic modification and biotechnology
    • 4. Ecology >
      • 4.1 Species, communities and ecosystems
      • 4.2 Energy flow
      • 4.3 Carbon cycling
      • 4.4 Climate change
    • 5. Evolution and biodiversity >
      • 5.1 Evidence for evolution
      • 5.2 Natural selection
      • 5.3 Classification of biodiversity
      • 5.4 Cladistics
    • 6. Human physiology >
      • 6.1 Digestion and absorption
      • 6.2 The blood system
      • 6.3 Defence against infectious disease
      • 6.4 Gas exchange
      • 6.5 Neurons and synapses
      • 6.6 Hormones, homeostasis and reproduction
  • Additional higher level (AHL)
    • 7. Nucleic acids >
      • 7.1 DNA structure and replication
      • 7.2 Transcription and gene expression
      • 7.3 Translation
    • 8. Metabolism, cell respiration and photosynthesis >
      • 8.1 Metabolism
      • 8.2 Cell respiration
      • 8.3 Photosynthesis
    • 9. Plant biology >
      • 9.1 Transport in the xylem of plants
      • 9.2 Transport in the phloem of plants
      • 9.3 Growth in plants
      • 9.4 Reproduction in plants
    • 10. Genetics and evolution >
      • 10.1 Meiosis
      • 10.2 Inheritance
      • 10.3 Gene pools and speciation
    • 11. Animal physiology >
      • 11.1 Antibody production and vaccination
      • 11.2 Movement
      • 11.3 The kidney and osmoregulation
      • 11.4 Sexual reproduction
  • Options
    • A. Neurobiology and behaviour >
      • A.1 Neural development
      • A.2 The human brain
      • A.3 Perception of stimuli
      • A.4 Innate and learned behaviour (AHL)
      • A.5 Neuropharmacology (AHL)
      • A.6 Ethology (AHL)
    • B. Biotechnology and bioinformatics
    • C. Ecology and conservation >
      • C.1 Species and communities
      • C.2 Communities and ecosystems
      • C.3 Impacts of humans on ecosystems
      • C.4 Conservation of biodiversity
      • C.5 Population ecology (AHL)
      • C.6 Nitrogen and phosphorus cycles (AHL)
    • D. Human physiology
  • BISV Revision
  • Giving back - BioKQQAnswers

Essential idea: Living organisms are able to detect changes in the environment.

The image show the delicate sensory hairs in the (rat's) inner ear. Sound causes vibrations in the air, which in turn causes the sensory hairs to move. The movement of sensory cells stimulates impulses in neurons which the brain interprets as sound.

Understandings, Applications and Skills

A.3.U1 Receptors detect changes in the environment. [Humans’ sensory receptors should include mechanoreceptors, chemoreceptors, thermoreceptors and photoreceptors.]
A.3.U2 Rods and cones are photoreceptors located in the retina.
A.3.U3 Rods and cones differ in their sensitivities to light intensities and wavelengths.
A.3.U4 Bipolar cells send the impulses from rods and cones to ganglion cells.
A.3.U5 Ganglion cells send messages to the brain via the optic nerve.
A.3.U6 The information from the right field of vision from both eyes is sent to the left part of the visual cortex and vice versa.
A.3.U7 Structures in the middle ear transmit and amplify sound.
A.3.U8 Sensory hairs of the cochlea detect sounds of specific wavelengths.
A.3.U9 Impulses caused by sound perception are transmitted to the brain via the auditory nerve.
A.3.U10 Hair cells in the semicircular canals detect movement of the head.
A.3.A1 Red-green colour-blindness as a variant of normal trichromatic vision.
A.3.A2 Detection of chemicals in the air by the many different olfactory receptors.
A.3.A3 Use of cochlear implants in deaf patients.
A.3.S1 Labelling a diagram of the structure of the human eye. [Diagram of human eye should include the sclera, cornea, conjunctiva, eyelid, choroid, aqueous humour, pupil, lens, iris, vitreous humour, retina, fovea, optic nerve and blind spot.]
A.3.S2 Annotation of a diagram of the retina to show the cell types and the direction in which light moves. [Diagram of retina should include rod and cone cells, bipolar neurons and ganglion cells.]
A.3.S3 Labelling a diagram of the structure of the human ear. [Diagram of ear should include pinna, eardrum, bones of the middle ear, oval window, round window, semicircular canals, auditory nerve and cochlea.]
[Text in square brackets indicates guidance notes]

​Presentation and notes

The presentation is designed to help your understanding. The notes outline is intended to be used as a framework for the development of student notes to aid revision.
Use the Cornell style template to collate your own notes for this topic.

Nature of science

Understanding of the underlying science is the basis for technological developments - the discovery that electrical stimulation in the auditory system can create a perception of sound resulted in the development of electrical hearing aids and ultimately cochlear implants. (1.2)

Theory of knowledge

Other organisms can detect stimuli that humans cannot. For example, some pollinators can detect electromagnetic radiation in the non-visible range. As a consequence, they might perceive a flower as patterned when we perceive it as plain. To what extent, therefore, is what we perceive merely an individual construction of reality?
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.Creative Commons License
Proudly powered by Weebly