Biospychology as level Flashcards
AS level
What is the role of the nervous system?
has two main functions:
TO collect, process and respond to information in the enviroment - TO co-ordinate the Working of different organs and cells
Function of the central nervous system?
Passes messages to and from the brain and connects nerves to the pns.
What is the cns made up of, and their role?
Spinal cord- an extension of the brain, responsible for reflex actions
Brain- centre of all conscious awareness.
What is the function of the pns?
And what is it divided into?
Transmits message via millions of neurons to and from the cns
Somatic nervous system & autonomic nervous system
Functions of somatic nervous system & autonomic nervous system?
Sns- 12 pairs of cranial nerves from the brain and 31 pairs of spinal nerves from the spinal cord
relays sensory and motor neurons to and from the spinal cord
Ans- regulates involuntary movements
What are the 2 parts of the ANS and their functions?
Sympathetic nervous system- involved in responses that help us deal with threats/emergencies e.g fight or flight
Parasympathetic nervous system- puts the body in the pre sympathetic state (relaxing the individual) once the threat has passed. This may take a while
These systems work in opposition to each other (antagonistic)
What are the reasons for these psychological change?
Increased heart rate- increase blood flow to organs and increase movement of adrenaline around body
Pupil dilation- increase light into the eye to enhance vision
What are examples of the Sympathetic and parasympathetic?
Sympathetic
Heart - increased heart rate
Eye - dilates pupils
Liver - stimulates glucose production
Parasympathetic
Heart - decreased heart rate
Eye - constricts pupils
Liver - stimulates bile production
Outline fight or fight response
Part 1
Anxiety and fear
acts as a mechanism to protect the body against Stress and danger.
• The sympathetic nervous System controls the “fight or plignt”,and it controls the necessary bodily changes needed when faced wich
a situation where we may defend ourselves or escape.
• In order to return everything to normal the parasymparnetic nervous System Kicks In. This
system is slow and may take several minutes
to get your body back to normal before the scare
Outline how the fight or flight works
Step 1
When someone enters a potentially stressful situation, the amygdala
(part of the limbic system in the brain) is activated.
- The amygdala responds to sensory input (what we see, hear, smell, etc.)
and connects sensory input with emotions associated with the fight or
flight response (e.g. fear and anger).
-If the situation is deemed as stressful/dangerous, the amygdala sends
a distress signal to the hypothalamus, which communicates with the body
through the sympathetic nervous system.
Outline how the fight or flight works
Step 2 -4
2) Sympathetic nervous system (SNS) is triggered by the
amygdala.
3) The SNS sends a signal to the adrenal medulla to release the hormone; adrenaline into the blood stream.
4) Adrenaline circulates all over the body causing a number
of changes. E.g. HEART RATE INCREASES, PUPILS
DILATE ETC
Outline how the fight or flight works
Step 5
When the threat has passed, the parasympathetic part of the
Autonomic nervous system is activated to dampen down the
SNS. E.g, heartbeat slows down, digestion begins again, pupils
constrict (rest and digest)
Functions of the 3 types of neurons
Sensory- They process information from the environment,
and carry this information to the CNS (brain and spinal cord)
Relay- Relay neurons are in the CNS, and connect motor and sensory neurons
Motor- Motor neurons carry signals from the CNS to effectors (muscles or glands)
How does a nervous impulse travel down a neuron
-A dendrite receives a signal from another neuron
-The signal is passed down the axon
-In many neurons, there is a myelin sheath surrounding the axon
this increases the speed at which the signals are transmitted
-The signal reaches the terminal buttons at the end of the neuron
-It is then passed along to the next neuron
What is action potential?
The information that arrives at the axon in the form of an electrical signal
Outline the process of synaptic transmission
1) The nervous Impulse (or action potential) arrives at the
presynaptic terminal, at the terminal button
2) This causes Vesicles containing neurotransmitter to move towards the presynaptic membrane
3) The vesicles bind to the presynaptic membrane and releases neurotransmitter Into the synaptic gap.
4)The neurotransmitter diffuses across the synaptic gap
(5) The neurotransmitter binds to receptors On the postsynaptic gap. These are complementary (Shape goes togetner)
6) This Causes channels in the pastsynaptic membrane to open and charged particles
to flow Into the postsynaptic terminal
7) The nervous Impulse can carry on Its
Journey down the next neuron
Examples of the endocrine system
Gland. Hormone. Function
Pancreas. Insulin. Regulate blood glucose
Ovaries. Oestrogen Regulating the
And Menstrual
Progesterone Cycle
Endocrine vs nervous system
Both communicate methods within the body
Ns sends messages electronically but es sends chemical messages
Ns sends messages really fast but es sends messages more slowly
What is the function endocrine system?
A network of glands throughout the body that releases chemicals called hormones into blood or bodily fluids.
The hormones communicate messages to the organs of the body, similarly to neurons- they prompt certain responses e.g adrenaline or fight or flight
