1. NEW Unit 3 NAR Revision
Higher Human Biology

2. Divisions of the nervous system and parts of the brain
Cerebral Cortex
Personality, intelligence, imagination
Recalls memories, motor control
Medulla
Regulates breathing

3. Memory
Information can be transferred from short term memory into long term memory by;
Rehearsal - repeating information over and over
Organisation- information is grouped into categories
Elaboration of meaning – additional information is added
Information can be lost from short term memory if it is displaced due to new information entering STM

4. Contextual Cue
A contextual cue is a “memory trigger” which aids the retrieval of information. Contextual cues relate to the time that the memory was first encoded.

5. Cells of the nervous system
Motor cell
Cell Body
Myelin sheath insulates the axon and so speeds up the rate of nerve transmission
Dendrite

6. Neurotransmitters
Neurotransmitters diffuse across the synapse from the neuron to the target effector (e.g. muscle).

7. Non-Specific Defence
Mast cells are a type of white blood cell which is present in most tissues, surrounding blood vessels and nerves.
Mast cells release histamine which causes the inflammatory response.
Histamine causes vasodilation and increased capillary permeability

8. Phagocytes
Phagocytes are cells which will engulf and digest pathogens.
Once the pathogen is inside the phagocyte, lysosomes fuse with the vesicle, digesting the bacterium.
VIDEO

9. Specific Defences
Lymphocytes have receptors that are specific to one antigen

10. Clonal Selection
Receptor

11. Clonal Selection
Lymphocyte Y undergoes cell division because the antigen is complementary to its receptor

12. Antibody action The binding of the antibodies causes the
inactivation of the pathogen (or the toxin it produces) and
pathogen to become more susceptible to phagocytosis

13. Herd immunity
Herd immunity is where a large % of a population have been immunised against a particular disease, they can offer protection to non immune individuals… This is because their chance of coming into contact with an infected individual is minimal. Threshold is the percentage of the population who need to be immunised by the vaccine to offer protection for people who are not vaccinated.

14. Read the questions carefully and bring a
Problem Solving
Selecting information, predicting
Calculating percentages, averages
Analysing information
Drawing conclusions from experimental data
REMEMBER!!!!
Read the questions carefully and bring a
CALCULATOR and RULER
Good luck