Behaviour Flashcards
Outline the organisation and roles of the autonomic nervous system
Sympathetic Nervous System
Most active in times of stress
The neurones of a pathway are linked at a ganglion just
outside of the spinal cord.
Pre-ganglion neurones are very short
Post-ganglion neurones secrete noradrenaline at the
synapse between neurone and effector
Effects of action include
Increased heart rate
Pupil dilation
Increased ventilation rate
Orgasm
Parasympathetic Nervous System
Most active in sleep and relaxation
The neurones of a pathway are linked at a ganglion within
the target tissue, so pre-ganglion neurones vary in length
Post ganglion neurones secrete acetylcholine as the
neurotransmitter at the synapse between neurone and
effector
Effects of action include:
Decreased heart rate
Pupil dilation
Decreased ventilation rate
Sexual arousal
Outline the organisation of the nervous system in terms of central and peripheral systems in humans
Nervous system
Central Nervous System
Peripheral Nervous System
Somatic Nervous System
Autonomic Nervous System
Sympathetic Nervous System
Parasympathetic Nervous System
Describe, the gross structure of the human brain, and outline the functions of the cerebrum, cerebellum, medulla oblongata and hypothalamus
Cerebrum
Control of all higher order processes such as memory,
language, emotions, thinking and planning
Cerebellum
Control and coordination of movement and posture
Medulla Oblongata
Control of breathing, heart rate and smooth muscle of the
gut
Hypothalamus
Control of the autonomic nervous system and some
endocrine glands
Describe the role of the brain and nervous system in the co-ordination of muscular movement
The conscious decision to move voluntarily is initiated in the cerebellum.
Neurones from the cerebellum carry impulses to the motor areas so that motor output to the effectors can be adjusted appropriately in these requirements
Describe how co-ordinated movement requires the action of skeletal muscles about joints, with reference to the movement of the elbow joint
Coordinated and appropriate movement requires the controlled action of skeletal muscles about joints.
This can be seen in the movement of the elbow joint
- Impulses arriving at the neuromuscular junction cause vesicles to fuse with the pre- synaptic membrane and to release acetylcholine into the gap
- Acetylcholine binds to receptors on the muscle fibre membrane (sarcolemma) causing depolarisation
- Depolarisation wave travels down tubules (T system)
- T system depolarisation leads to Ca2+ release from stores in sarcoplasmic reticulum Ca2+ binds to proteins in the muscle, which leads to contraction
- Acetylcholinesterase in the gap rapidly breaks down acetylcholine so that contraction only occurs when impulses arrive continuously
Explain the sliding filament model of muscular contraction
- Myosin head groups attach to the surrounding actin filaments forming a cross bridge
- The head group then bends, forming the thin filament to be pulled along and so overlap more with the thick filament.
This is the power stroke. ADP and Pi are released
- The cross bridge is broken as new ATP attaches to the myosin head
- The head group moves backwards as ATP is hydrolysed to ADP and Pi.
It can then form a cross bridge with the thin filament along and bend again.
Outline the role of ATP in muscular contraction, and how the supply of ATP is maintained in muscles
Role
Energy from ATP is required to break the cross bridge
connection and re-set the myosin head forwards
Maintenance
Aerobic respiration in mitochondria
Anaerobic respiration in sarcoplasm
Transfer of phosphate group from Creatine Phosphate to
ADP in sarcoplasm
Define behaviour
The way organisms respond to the environment, which enables them to survive and seek out favourable environments
Explain the advantages to organisms of innate behaviour
It does not need to be learned
It has immediate survival value for a young, inexperienced animal in a dangerous situation
It is appropriated for invertebrates with a short live span that do not have time to learn
It required few neurones
It is likely to be appropriate for the animal’s habitat, as the alleles controlling it will have been subject to natural selection
Compare and contrast the action of synapses and neuromuscular junctions
Synapse
Post synaptic membrane is the cell surface membrane of a neurone
Neurotransmitter may be ACh, noradrenaline, glutamate or another transmitter
Depolarisation of the post synaptic membrane may be stimulatory or inhibitory
Neuromuscular Junction
Post synaptic membrane is the cell surface membrane of a muscle
Neurotransmitter is ACh
Depolarisation of post synaptic membrane is stimulatory
Both
Neurotransmitter is secreted, diffuses across a cleft, binds to receptors in the postsynaptic membrane and is finally broken down
Outline the structural and functional differences between voluntary, involuntary and cardiac muscle
Voluntary
Striated
Cylindrical cells are multinucleate
Found attached to bone
Controlled by the somatic nervous system
Contracts quickly; tires easily
Involuntary
Unstriated
Spindle-shaped cells each have a single nucleus
Found in the walls of tubular structures, such as the gut, blood vessels and ducts
Controlled by the autonomic nervous system
Contracts slowly; fatigues slowly
Cardiac
Semi-striated
Cylindrical cells, each with a single nucleus, branch and connect with other cells
Found only in the heart
Controlled by the autonomic nervous system
Contracts spontaneously without fatigue
Responses to environmental stimuli in mammals are co-ordinated by…
Nervous and endocrine systems
Describe escape reflexes, taxes and kineses as examples of genetically-determined innate behaviours
Escape reflexes
A particular stimulus brings about an automatic response, the function of which is to avoid predators.
Earthworms withdraw underground in response to vibrations in the ground
Taxes
A directional movement in response to an external stimulus.
Woodlice move away from light to be less visible to predators and less liable to desiccation
Kineses
A movement in response to an external stimulus. The rate of movement is related to the intensity, but not the direction, of a stimulus.
When woodlice are placed in dry/bright conditions, they will move around rapidly and randomly until they are in more suitable conditions
Explain the meaning of the term learned behaviour
Animal responses that change or adapt with experience
Describe habituation, imprinting, classical and operant conditioning, latent and insight learning as examples of learned behaviours
Habituation
Animals learn to ignore certain stimuli because repeated exposure to the stimulus results in neither reward or punishment.
It avoids wasting energy in making escape responses to non-harmful stimuli
Imprinting
Young animals being associated with another organism, usually the parent.
After that, they will only follow and learn from objects that look like the first objects. This helps the young learn skills from the parents
Classical conditioning
A form of adaptive learning in which the innate response is modified.
The animal learns to respond to a stimulus that is different from the usual stimulus
Operant conditioning
A form of adaptive learning in which an animal learns to carry out a particular action in order to receive a reward or avoid an unpleasant experience.
Latent learning
Behaviour that is not directed towards a particular outcome.
Animals explore new surrounding and learn information that has no apparent value at the time, but may be useful at some time.
Insight learning
A form of learning in which an animal integrates memories of two or more earlier actions to produce a new response or gain a reward.
The organism has the ability to think and reason in order to solve problems or deal with situations that do not resemble simple fixed, reflex responses or the need for repeat trial and error
