What two groups is the nervous system made up of?
- Central nervous system: controls the body by processing and responding to sensory input from the peripheral nervous system.
- Peripheral nervous system: nerves composed of all the nerves and ganglia outside the brain and spinal cord that communicate information to and from the CNS.
What is the central nervous system made up of?
- The brain: three main sections.
- The spinal chord: bundle of nerve fibres connecting the brain with the peripheral nervous system runs from the brain stem to the lower middle spine.
What is the brain made up of?
- Forebrain: exterior, front. Largest part of the brain. Most conscious and rational. Include cerebral hemispheres.
- Midbrain: centre. Connects hind brain with mid brain.
- Hindbrain: rear brain. Also known as reptilian- not rational.
What is the peripheral nervous system.
- Somatic nervous system: Voluntary nervous system. Carries information to the CNS from the senses and from the CNS to the skeletal muscles. (movements you chose to do). Senses->CNS->skeletal muscles.
- Autonomic nervous system: Involuntary movements. Communication between CNS and non-skeletal muscles. Most bodily functions.
What is the somatic nervous system made up of?
- Sensory nerves: send impulses from the body to the CNS (bringing in).
- Motor nerves: sends impulses from the CNS to organs (bringing out/doing).
What is the autonomic nervous system made up of?
- Sympathetic: (stress) arouses the body. Fight. Flight. Freeze.
- Parasympathetic: (peace) calms after arousal.
Summarise the whole nervous system.
Two main parts: PNS and CNS.
CNS: Brain & Spinal chord.
Brain: Fore, Mid, Hind.
PNS: Somatic and Autonomic.
Somatic: Sensory & Motor.
Autonomic: Sympathetic & Parasympathetic.
Name all the parts of a neuron and where they are positioned.
- Dendrites: long branches on the left side. The same side that has the nucleus.
- Nucleus: small part inside the cell body which is the same side as the dendrites.
- Cell Body/Soma: area surrounding the nucleus and has dendrites attached to it.
- Axon: the whole path connecting both sides of the neuron.
- Myelin Sheath: the segments surrounding the schwann cell that is located along the axon path.
- Node of Ranvier: the small parts connecting the schwann cells and the myelin sheaths.
- Schwann Cell: the small parts on the axon inside the myelin sheaths.
- Axon Terminal: the branches at the end of the axon on the left side. separate from the cell body side.
- Synapse/terminal buttons: small parts at the very end of the axon terminal branches.
What are the 3 types of neurons?
- Sensory: receive sensory info and send it up to the CNS (afferent)
- Interneurons: Integrate sensory input.
- Motor: receive info from CNS and send it out (efferent).
What is a neuron?
Neurons are cells that are specialised to receive, process, and/or transmit information to other cells within the body. These are also known as nerve cells.
What is the function of each part of a neuron?
- Dendrites: receives information from communicating neurons.
- Cell body/soma: control metabolism and maintenance of the neuron.
- Nucleus: contains the instruction of the neuron and keeps it functioning.
- Axon: gets information from the soma to the communicating soma.
- Myelin Sheath: protect and insulate axons and enhance the transmitting of electrical impulses.
- Axon terminal& terminal buttons: transmits information over to the next neuron.
Two neurons connect at their dendrites touching terminal buttons/synapses (terminal buttons (presynaptic) going to the dendrites (postsynaptic)). What makes up this synapse?
-Synapse:
1. Axon: makes up the whole inner part of the synapse.
2. Synaptic vessel: Little parts inside the axon and there are many of them.
3. Neurotransmitter: small little electric impulses going from the synapse over to the dendrites.
4. Synaptic cleft: the gap between the axon and the dendrites.
-Dendrites:
1. These have receptors in them the take up the neurotransmitters coming from the synapse.
