5.1.5 Animal Responses Flashcards
Define central nervous system
made up of the brain and spinal cord
Define peripheral nervous system
made up of all the neurones that connect the CNS to the rest of the body
(divides into autonomic and somatic nervous system)
Define somatic nervous system
- part of nervous system that is under conscious control
Define autonomic nervous system
- part of nervous system that is under subconscious control (involuntary)
Define sympathetic nervous system
(division of autonomic nervous system)
- if outcome increases activity
e.g. increase in heart rate
Define parasympathetic nervous system
(division of autonomic nervous system)
- if outcome decreases activity it involves parasympathetic nervous system
e.g. decrease in heart rate
What are 4 differences between somatic nervous system and the autonomic nervous system?
- autonomic is involuntary and somatic is under voluntary control
- autonomic mostly non or lightly myelinated, somatic mostly myelinated
- autonomic has atleast 2 neurones to connect CNS with effector, somatic 1 neurone to connect CNS with effector
- autonomic effectors are cardiac muscle, smooth muscle and glands
somatic effectors are skeletal muscles - autonomic both parasympathetic and sympathetic motor neurones to same effector
only somatic motor neurones to each effector
What 2 sub systems does the autonomic nervous system split into?
- sympathetic and parasympathetic nervous system
Define antagonistic system
antagonistic - when the action of one system opposes the action of the other
Define antagonistic system in relation to the sympathetic and parasympathetic nervous systems and how they coordinate responses
- under normal conditions impulses are passing along the neurones of both systems at a relatively low rate
- changes to conditions lead to an altered balance between the 2 systems which leads to an appropriate response
Compare the structure and function of the sympathetic and parasympathetic nervous system
Parasympathetic NS:
- most active in rest
-neurones of a pathway linked at ganglion within target tissue (long pre-ganglion, short post-ganglion neurone)
- post-ganglionic neurones secrete acetylcholine at synapse btw neurone +effector
- heart rate decreased
- pupil size narrow=constrict
- ventilation rate decreases
-saliva production increase
- smooth muscle in bronchiole walls contract
- decreased urine production
- secrete gastric juice
- increased digestion
Sympathetic NS:
-most active times of fight/flight
- neurones of a pathway linked at a ganglion outside spinal cord ~(long post-ganglion neurone, short pre-ganglion)
- post-ganglion neurones secrete noradrenaline at synapse btw neurone +effector
- heart rate increase
- pupil size wider= dilated
- ventilation rate increase
- decreased saliva production
- smooth muscle in walls of bronchioles relax
- increase urine production
- reduced peristalsis
- reduced peristalsis
Label a diagram of the brain - cerebrum, cerebellum, medulla oblongata, hypothalamus, pituitary gland
What is the structure of the cerebrum?
- split into 2 hemispheres (left and right)
- 2 hemispheres connected by the corpus callosum
-left hemisphere=Rhs body
-right hemisphere=Lhs body - outermost layer is cerebral cortex
- cerebral cortex divided into 4 lobes -(frontal, parietal, occipital, temporal)
- 3 types of area in cerebral cortex - (association, sensory, motor)
What are the roles of the sensory areas, association areas and motor areas of the cerebral cortex?
Sensory- receives impulss from receptors and passes it onto association areas
Association - compare input with previous experiences in order to analyse and act on input
Motor - send impulses to effectors to bring about response
What is the role of the cerebellum in coordinated musclar movement?
- if muscle movement conscious its from cerebrum
- cerebellum coordinates info from retina/balance organs/spindle fibres to make adjustments for fine control (posture/balance/nonvoluntary move)
What is the structure of the pituitary gland and its location?
located: at base of hypothalamus
- divided into 2 sections:
- anterior pituitary (front) - produces hormones for growth+reproduction
- posterior pituitary (back) - stores and releases hormones produced by hypothalamus e.g. ADH
What is the role of the cerebrum?
- controls voluntary actions e.g. learning/memory/personality/conscious thought
What is the role of the cerebellum?
- controls unconscious functions e.g. posture/balance/nonvoluntary move)
What is the role of the medulla oblongata?
- used in autonomic control (involuntary) - controls heart rate/breathing rate (swallowing/peristalsis/coughing)
What is the role of the hypothalamus?
- the main controlling region for autonomic (involuntary) nervous system
- has 2 centres - parasympathetic NS and sympathetic NS
Functions: - control complex patterns of behaviour (feeding/sleep/aggression)
- monitor blood plasma composition
- regulate temp and water balance
- produce hormones
What is the role of the pituitary gland?
- stores and releases hormones to regulate body functions
- anterior (front) and posterior (back) sections
Define reflex action
an involuntary response to a sensory stimulus
Define reflex arc
the pathway of neurones involved in reflex action
Define stimulus
detecable change in external or internal environment of an organism
Define receptor
an organ or cell that detects stimulus and creates an action potential in the sensory neurone
Define effector
muscle/gland which carries out bodys response to a stimulus
Define response
the way a body reacts to stimulus
Draw, label a diagram to show the arrangement of neurones in the ‘withdrawal of hand from a heat stimulus’ reflex arc and the actions that occur in the stimulus-response pathway
Draw and label a diagram to show a muscle fibre and its components of the cell and its functions
Define muscle fibre
- a muscle cell that makes up skeletal muscles and is composed of many myofibrils that contract when stimulated
Define myofibril
- provide the cell with ability to contract and generate force
Define sarcolemma
the cell surface membrane of a muscle fibre
Define sarcoplasm
the cytoplasm of a muscle cell
Define sarcoplasmic reticulum
the endoplasmic reticulum of muscle cells
Define t-tubule
- small tubes made from sarcolemma
- electrical impulses transmitted from sarcoplasm to centre of muscle fibre
Define sarcomere
- make up myofibrils by joining repeating units
