Human Bio- Nervous system part 1

What are the two main divisions of the nervous system?

Central nervous system (CNS) and peripheral nervous system (PNS)

What structures form the CNS

Brain and spinal cord

What structures form the PNS

Nerves and ganglia outside the CNS

What is the function of the CNS

Recieves information from PNS, coordinates responses and sends instructions to effectors

What is the function of the PNS

carries sensory information to and from the CNS

what are the 2 main divisions of the PNS

Efferent and Afferent

What is the function of the Efferent division of the PNS

carried information away from the CNS to effectors

What is the function of the afferent division of the PNS

carries information from sensory neurons to CNS

What is the 2 main divisions of the efferent nervous system and function

• Somatic- carry messages to skeletal muscles

• Autonomic - carries messages to internal organs and muscles

What are the 2 main divisions of the afferent nervous system and functions

• Somatic- sends messages from skin and muscles to CNS

• Visceral- sends messages from internal organs to CNS

what are the 2 divisions of the autonomic nervous system and functions

• Sympathetic- prepares body for flight or fight response

• Parasympathetic- supports rest and digest response

Compare sympathetic and parasympathetic effects on the heart

• Sympathetic- increases heart rate

• Parasympathetic- decreases heart rate

Compare sympathetic and parasympathic effect on digestion

• Sympathetic: slows down digestive activity

• Parasympathetic: stimulates digestive activity

What are the functional types of neurons

• Sensory/afferent - carry messages from receptor to CNS

• Motor/efferent- carry messages from CNS to effectors

• Interneurons- located in CNS and link sensory and motor neuron

What are the structural types of neurons

• Multipolar, Bipolar, unipolar and psudounipolar neurons

What is a multipolar neuron

have one axon and multiple dendrites and includes most interneurons in CNS and motor neurons

Where are bipolar neurons found and what is their description

• eye, ear and nose

• have one axon and one dendrite

where are pseudounipolar neurons found

in most sensory neurons that carry messages to spinal cord

What are nerve fibres called when outside the CNS

nerves - bundles of nerve fibres held together by connective tissue

what is the function of myelin sheaths

• acts as insulator

• protects axon from damage

• speeds up movement of nerve impulse along axon

what are the gaps between myelin sheath called

nodes of ranvier

what is the outermost coil of Schwann cell called and function

• Neurilemma

• Helps repair injured fibres

what forms mylein sheaths

Schwann cells

Where are interneurons located

inside the CNS

What are the functional regions of the brain

Cerebrum, corpus callosum, cerebellum, medulla oblongata, hperthalamus

What is the function of the cerebrum

Conscious thought, memory, sensory interpretation and voluntary movement.

What is the function of the cerebellum

coordinates voluntary movement, posture, balance and fine motor control

What are the 4 lobes of the Cerebrum and the functions

• Frontal lobe

• Parietal lobe

• Temporal:

• Occipital:

what is the function of the frontal lobe

Conscious thought, memory, sensory interpretation and voluntary movement.

What is the function of the occipital lobe

vision

What is the function of the parietal lobe

• processing temp, touch, taste, pain and movement

What is the function of the temporal lobe

Processing memories and linking them with senses, and receives auditory information

What is the difference between grey and white matter

• Grey matter: consists of unmyelinated axons

• White matter: consists of myelinated axons

what is the structure of cerebral cortex

has folded patterns that increase surface area called gyri

what is the function of the Corpus callosum

transfers sensory, motro and cognitive information between 2 hemispheres

connects the 2 halves of the brain

What is the function of the hypothalamus

• regulates vital body functions

• controls homeostasis

• regulates emotions

• hormonal regulation

what is the function of the medulla oblongata

controls automatic functions such as breathing, heart rate, blood pressure and swallowing

what is the function of the spinal cord

take messages between brain and PNS

Compare white and grey matter in the brain and spine

• Grey matter in brain is out side whereas in spine it is in centre

• White matter in brain is in centre and in spine it is outside