Unit 3 AOS 1 SAC 1 - Nervous System Flashcards
Jonah was very scared of spiders. One morning, he walked into the bathroom and saw a very large spider on the mirror. He screamed and ran out of the bathroom. His mouth was dry, his heart was beating very fast and he was also breathing quickly.
With reference to the human nervous system, explain why Jonah would have experienced these changes in his body.
Seeing a spider (a fearful stimulus) activated Jonah’s sympathetic nervous system. The activation of the sympathetic nervous system produced the physiological responses characteristic of the fight-or-flight response including increased heart rate and breathing.
Pam is taking part in an experiment that involves sorting beads into two groups while wearing a blindfold. The first part of this task involves Pam picking up each bead and deciding whether it is rough or smooth. The second part of this task involves Pam placing the bead in its appropriate group.
What type of neuron is responsible for enabling Pam to tell if a bead is rough or smooth?
Sensory neurons
What is the response called where a motor action is initiated by interneurons in the spinal cord?
The spinal reflex
Neurons communicate using what sort of energy?
Electrochemical energy
What is glutamate responsible for?
Memory
What is GABA responsible for?
Reducing anxiety
Name two ways that neurotransmitters can be interrupted.
Alcohol and stress.
Explain a difference in the function of glutamate and GABA in the nervous system.
Glutamate is the brain’s primary excitatory neurotransmitter and makes a post-synaptic neuron MORE likely to fire an action potential whereas GABA is the brain’s primary inhibitory neurotransmitter which makes a post-synaptic neuron LESS likely to fire an action potential.
Brain role in the CNS
The ‘engine room’ of the NS. It receives and processes information from the rest of the body and generates responses to it.
Abi is outside on a cold day waiting for a bus. She starts to feel cold so she decides to put on a jumper. Outline the role of both sensory and motor neurons in this scenario.
The sensation of Abi feeling cold would be transmitted via sensory neurons from her skin receptors to her central nervous system. After deciding that she feels cold, the information will be sent via motor neurons to her arms, enabling the movement of putting on a jumper
Using an example, describe how a neurotransmitter can produce an ‘excitatory’ effect.
The release of neurotransmitters such as glutamate from the presynaptic neuron can have an excitatory effect. This will make the postsynaptic neuron more likely to fire.
Identify and distinguish between the functions of the two divisions of the peripheral nervous system in responding to sensory stimuli.
The somatic nervous system is responsible for voluntary responses through detection of sensory stimuli from the environment; for example, tactile information such as the heat felt on the skin from a shower, along with the activation of the skeletal muscles which enables the individual to respond to the sensory stimuli.
The autonomic nervous system is responsible for involuntary responses to sensory stimuli through changes to the visceral muscles which regulate the activity of vital organs such as the heart; for example, an increase in sweat gland activity in response to moving to a warm environment
Parkinson’s disease is a neurodegenerative disease of the central nervous system. Sufferers can experience physiological symptoms such as uncontrollable tremors in their hands.
Explain the physiological cause underlying the development of Parkinson’s disease.
Parkinson’s disease is due to the degeneration of neurons in the substantia nigra which decreases the amount of dopamine available for motor activity. These dopamine neurons also release dopamine which has an inhibitory effect on neuronal activity
Describe how the lock-and-key process works to create excitatory effects on the nervous system. In your response, refer to a relevant neurotransmitter.
The lock-key-process is a metaphor that explains the means by which a neurotransmitter influences the response of a post-synaptic neuron.
Each neurotransmitter acts as a key, which has a chemically distinct shape.
Receptor sites on the post-synaptic neuron have complementary shapes that can be affected by the relevant neurotransmitters.
Neurotransmitters that have an excitatory effect, such as glutamate, make the post-synaptic neuron more likely to generate an action potential when they are received by the relevant receptor site.
Priya decides to join her friends in a game of soccer. Describe the role of both the central and somatic nervous system required for Priya to kick the soccer ball during the game.
Central nervous system - either of the following points: one mark for each relevant point
Priya would coordinate the movement in her central nervous system (brain).
Priya would transmit the motor signals required for making the movement down her spinal cord.
Somatic nervous system:
The somatic nervous system would carry the motor signal from the spinal cord to the relevant skeletal muscles required to make the kicking movement.
Functions of the human nervous system
● To receive sensory information from the internal and external environment
● To process information and transmit it around the body
● To organise a coordinated response to the information
The nervous system divisions
○ The central nervous system
i. Brain
ii. Spinal cord
○ The peripheral nervous system
i. The autonomic nervous system
ii. The somatic nervous system
- The sympathetic nervous system
- The parasympathetic nervous system
CNS
Define
2 components and roles
Consists of the brain and the spinal cord, responsible for transmitting neural messages to and receiving neural messages from the peripheral nervous system
- The brain is the control centre for the body, allowing the body to respond to information both from within and outside of the body
- The spinal cord is the information route via which these messages are received and transmitted to other parts of the body
