Biology Unit 3 Flashcards
component of the central nervous system
Brain -spinal cord
Somatic nervous system
Controls voluntary activities and is brought about by skeletal muscles
Autonomic nervous system
Controls involuntary activities and is brought about by smooth muscle
Describe the relationship between sympathetic and parasympathetic muscle fibres
They are antagonistic
What are the sympathetic actions
Increase heart rate and breathing -decreases peristalsis
What are parasympathetic actions
Decrease heart rate and breathing- increase peristalsis
What 2 neurons are present in the somatic nervous system
Motor and sensory neurons
What is the function of the cerebral cortex
Conscious thought and memory
What is the region of the cerebral cortex that receives neuron impulses from sensory organs
Motor area
What is the function of the motor area of the cerebral cortex
Sends nerve impulses to muscles and glands
What is the function of the corpus callosum
Transport information from the cerebral hemispheres
What is sensory memory
All the visual and auditory information that enters the brain
what happens to information entering short term memory
Stores information for a short period of time process and data to limited extent -information can be displaced
2 characteristics of short term memory
limited capacity and proof by chunking
what is chunking
Combining pieces of information interrelated groups
what is the serial position effect
objects early in the sequence or recalled object at the end of the sequence
3 methods of encouraging the transfer of information to long term memory (roc)
rehearsal organisation collaboration
what are contextual cues
contextual Cues related to the time and place of the original encoding
what is the function of the myelin sheath
act as insulation and increases the speed of impulse conducting base allow low-level stimuli to be summated added together to cause impulses to be passed on
what is summation
allow low level stimuli to be summoned to cause impulses to be passed on
what’s the difference between an axon and a dendrite
axons carry nerve impulses away from cell bodies dendrites carry nerve impulses towards cell bodies
whats the function of endorphins
Reduction of pain intensity euphoric feelings release sex hormones
whats the function of dopamine
induces feelings of pleasure reinforces behaviour in the reward pathway
what is the function of agonist drugs
bind to and stimulates receptors to mimic neurotransmitters so impulsive passed on
2 way how neurotransmitters can be removed from the synapse cleft
by degradation by enzymes and by reabsorption reuptake by presynaptic membrane
what’s the difference between drug addiction and drug tolerance
sensitisation increase in neural receptors through exposure to antagonists Can lead to addiction the exposure to agonistic drugs can lead to tolerance
what are non- specific defences
Defences are general to any all individual pathogens
how does the epithelium provide a physical barrier against pathogens
epithelium can form a barrier which prevents entry of pathogens
2 examples of secretions from epithelial cells that provide defences against pathogens
acid secreted by cells in the stomach epithelium enzymes secreted by cells in stomach epithelium muscle secreted from a cell in stomach tears
Name the molecules released by phagocytes which attract other phagocytes to the site of infection
antigens
Describe the role of cytokines in cellular defence
attract more phagocytes to the site of the infection base defence which is specific and response to a particular antigen and pathogen
State what is meant by specific cellular defence
hey are proteins on the surface of pathogen which trigger an immune response
describe the role of non-self antigens in the immune response
divide repeatedly to produce a cloned
describe what happens to be late besides immediately after it binds with an antigen
hypersensitivity b lymphocytes response to a normal harmless antigen
responses allergic response
immune system regulation feel your least a response of T lymphocytes to self antigens
autoimmune response
long-term existence of memory cells following a primary exposure to antigen allow rapid greater immune response to secondary exposure the same antigen
What is immunological memory
caused by HIV which attracts and destroyed t lymphocytes increases individuals of vulnerability to opportunistic defectors
describe the cause and effect of AIDS on an individual’s health
substances containing antigens that produce an immune response without symptoms of disease
Describe what is meant by a vaccine
substance added to Vaccines to enhance the immune response
explain the role of adjuvant in immunization
occurs when large percentage of population in immunized are immunised against infection important in reducing the spread of disease
describe what is meant by herd immunity
occurs when a papa dim changes its antigens are memory cells are not effective against them
describe what is meant by antigenic variation
scientifically planned experimental procedures to test a new drug is safe effective for licensed
What is a clinical trial explain why it is good practice to create randomised groups in a clinical trial
to let the group and not biased towards a certain age gender of participants
State why it is good practice to have as many participants as possible and clinical trial
to increase the reliability of data obtained reduce experimental hatters
describe what is meant by Placebo-controlled trial
upper site is a blank which does not contain the drug under trial but is administered in the same way
describe what is meant by double-blind trial
needed the participants northern doctors know which group of individuals has the vaccine
