Animal Responses Flashcards
What is the autonomic nervous system?
Part old the nervous system responsible for controlling the involuntary motor activities of the body.
What is the somatic nervous system?
The motor neurones under conscious control.
What much a communication system enable?
Detection of changes in the environment
Cell signalling to occur between all parts of the body
Coordination of a range of effectors to Cary out responses to the sensory input
What is the nervous system divided into?
The CNS and the PNS
What is the PNS divided into?
The sensory system and the motor system.
What is the motor system divided into?
The somatic system and the autonomic system.
What type of neurone id the brain mostly comprised of?
Relay neurones
What does the grey matter consist of?
Non-myelinated relay neurones
What does the white matter consist of?
Myelinated neurones
What is the role of the PNS?
To ensure rapid communication between the sensory receptors, the CNS and the effectors
What does the PNS consist of ?
Sensory and motor neurones?
What does the somatic nervous system consist of?
Motor neurones that conduct action potentials from the CNS to the effectors that are under voluntary control
What does the autonomic system consist of?
Motor neurones that conduct action potentials from the CNS to the effectors that are not under voluntary control
What are the features of the sympathetic nervous system?
Short pre gangleonic neurones
Long post gangleonic neurones
Uses noradrenaline and adrenaline
Increases activity
Features of the parasympathetic system?
A few nerves leading out of the CNS
Ganglia in the effector tissue
Long pre gangleonic neurones
Short post gangleonic neurones
What are the four main parts of the brain?
The cerebrum the cerebellum the hypothalamus/pituitary the medulla oblongata
Structure of the cerebrum
Two hemispheres which are connected by major tracts of neurones called the corpus callosum
The outer layer of the cerebrum is called the cerebral cortex.
What does the cerebrum control ?
Cpnscious thought
Actions
Emotional responses
Intelligence reasoning and decision making
Factual memory
The cerebellum structure?
Has half of the neurones in the brain
Cerebellum functions.
Maintaining body position and balance
Judging the position of objects and limbs
Tensioning muscles in order to use tools
Structure of the hypothalamus and pituitary complex structure.
Contains its own sensory receptors for negative feedback.
Function for hypothalamus and pituitary complex
Temperature regulation
Osmoregulation
Releases various hormones
Role of medulla oblongata
The cardiac centre regulates circulation and blood pressure
Regulates heart rate/rate of breathing
How many neurones do reflex pathways usually consist of?
3
What is the blinking reflex?
Temporary closure of the eyelids to protect the eyes from damage
What is the corneal reflex
A reflex mediated by the sensory neurone causing the eyelid to shut when the cornea is touched.
What is the optical reflex?
Protects the light sensitive cells of the retina from damage.
What is adenyl cyclase?
An intracellular enzyme which is activated by certain hormones
Cyclic AMP
A secondary messenger released inside cells to activate a response.
What are examples of output to effectors.
Action potentials in the somatic nervous system
Action potentials in the sympathetic nervous system
Release of hormones via the hypothalamus and pituitary
What are some physiological changes associated with fight or flight?
Pupils dilate
Heart rate and blood pressure increase
Blood glucose levels increase
Ventilation rate and depth increase
Coordination of the fight or flight response
Inputs feed into the sensory centres in the cerebrum
Which passes signals into the association centre
If a thread is recognised the cerebrum stimulates the hypothalamus
Hypothalamus increases activity.
What effect does increasing the sympathetic nervous system have on the effectors.
Increases the activity
How does fight or flight engage a long term response.
Endocrine system
what is the importance of pumping blood around the body?
Transport of oxygen and nutrients
Removal of waste
Distribute heat around the body
How can the heart action be modifies?
Raising or lowering the heart rate
Altering force of contractions of ventricular walls
Altering the stroke volume
What does the heart muscle being myogenic if mean?
It can initiate its own beat at regular intervals
What are some examples of sensory input at the cardiovascular centre?
Stretch receptors in muscles detect movement of the limbs these send impulses
Chemoreceptors in carotid arteries
The concentration of CO2 in the blood
Stretch receptors in the walls of carotid stimulus.
What is cardiac muscle?
Muscle found in the heart walls
What is a neuromuscular junction?
The structure at which a nerve meets the muscle it is similar in action to a synapse
Why are muscles arranged in opposing pairs?
Because they cannot elongate without an antagonist.
Structure of involuntary muscle.
Individual cells tapered at both ends each cell about 500micrometers long and 5micrometers wide.
How does involuntary muscle contract.
Slowly and regularly (controlled by autonomic nervous system).
Cardiac muscle structure.
Individual cells form long fibres which form cross bridges
The cells are joined by intercalated discs.
How does cardiac muscle contract?
It contracts continuously throughout life it can contract powerfully and does not fatigue easily.
What is the membrane around the skeletal muscle?
Sarcolema
What is the junction between the nervous system and the muscle called?
Neuromuscular junction.
What is a motor neurone?
An electric signal which connects to multiple muscle fibres causing them to contract and resulting in a stronger contraction.
Creatine phosphate?
A compound in muscle that acts as a store of phosphates and can supply phosphates to make ATP rapidly.
What units are myofibrils broken down into?
Thin filaments which are aligned to make up the light band.
Thick filaments which make up the dark band.
What is a sarcomere
The distance between two z lines.
How long is a sarcomere at rest?
2.5micrometers
Heat are the thin filaments?
Actin
What is wound around actin
Tropomyosin
What does the thick filament consist of?
A bundle of myosin molecules
What happens during contraction
The thick and thin filaments slide past eachother
What alters the shape of troponin?
Calcium ions from the sarcoplasmic reticulum
How do the thick filaments slide past the thin filaments?
Myosin heads bind to the actin
The myosin heads move pullin actin filaments
The myosin head detaches
What part is ATP used in in the contraction of muscles?
The movement of the myosin head
How is ATP supplied?
Aerobic respiration
Anaerobic respiration
Creatine phosphates is broken down.
