Animal Responses Flashcards
Which part of the nervous system controls unconscious activities?
The Autonomic Nervous System e.g. digestion
What does the Sympathetic Nervous System do?
‘Fight-or-flight’ response, gets the body ready for action
What is the role of the Cerebrum?
Conscious thought, learning, hearing and vision
What is the role of the medulla oblongata?
Controls autonomic functions-heart rate and breathing rate
What is the role of the cerebellum?
Muscle coordination, posture and balance
What is the role of the pituitary gland?
Controls hormones released by body glands, controlled by the hypothalamus.
Role of the hypothalamus.
Maintains body temperature, blood water potential and produces hormones that control the pituitary gland.
What are the neurotransmitters of the sympathetic and parasympathetic nervous system?
Sympathetic=noradrenaline
Parasympathetic=acetylcholine
Describe the responses of the Parasympathetic nervous system.
‘Rest and digest’
Reduces breathing rate, diameter of airways and blood flow to skeletal muscles
Constricts pupils, liver stores glucose
Increases Persitalsis
What reflex arc is triggered if the cornea is stimulated and why does it occur?
Blinking reflex- eyelid closes to prevent anything from entering eye.
Describe the reflex arc if you strike the patellar tendon.
Knee-jerk reflex
1.Stretch receptors in the quadriceps muscle detect the muscle is being stretched.
2. A nerve impulse is passed along a sensory neurone, which communicate directly with a motor neurone in the spinal chord- no brain or no relay neurone
3. The motor neurone carries the nerve impulse to the effector (the quadriceps muscle) causing it to contract and the hamstring muscle to relax.
4. The lower leg moves forward
What does the pituitary gland release and what does it do during a ‘fight or flight’ response?
ACTH
Causes the cortex of the adrenal gland to release steroidal hormones.
What does the pituitary gland release and what does it do during a ‘fight or flight’ response?
ACTH
Causes the cortex of the adrenal gland to release steroidal hormones.
List the effects of noradrenaline and adrenaline.
-Heart rate raised
-Muscles around the bronchioles relax-deeper breathing
-Glycogenesis
-Erector pili muscles contract
-Muscles in arterioles supplying the skin and gut constrict
-Muscles in arterioles supplying the heart, lungs and skeletal muscle dilate
What catalyses the production of the second messanger?
Activated adenylyl cyclase
What is the second messanger?
Cyclic AMP (cAMP)
What are pressure receptors called and what are they stimulated by?
Baroreceptors
Stimulated by high and low blood pressure
What are chemical receptors called and what do they monitor?
Chemoreceptors
Monitor oxygen levels,carbon dioxide levels and the pH in the blood
Where are the impulses sent to initially from the pressure and chemical receptors?
Medulla
Where are the impulses sent to after the medulla and what substance is released in order to reduce the heart rate?
Vagus nerve and acetylcholine
Where are the impulses sent to after the medulla and what substance is released in order to increase the heart rate?
Accelerator nerve and noradrenaline
What does the sinoatrial node do in order to decrease the heart rate?
Decreases frequency of waves of excitation from the SAN.
