Endocrine and nervous Flashcards
1
Q
NERVE IMPULSES
NERVE TRANSMISSION
A
- Sodium and potassium cause weak electrical charge across the membrane of the neurone (resting potential), the membrane is said to be polarised.
- When the neurone is stimulated the action of the sodium and potassium in the membrane pump is interrupted.
- This changes the permeability of the membrane. That allows the sodium to flood into the cell and the potassium to leak out.
- This reverse electrical charge across the membrane (action potential) - t=he cell membrane is said to be depolarised.
- depolarisation down nerve fibre in small steps - nerve impulses as soon as the nerve impulses pass, membrane pumps are re-activated and resting potential restored.
- myelinated fibres impulses jumps from node to node - saltatory conduction
2
Q
NERVE IMPULSES
MYELINATED / UN-MYELINATED
A
- Myelinated neurones - have myelin sheath and use saltatory conduction
- Myelin - white phospholipid covering around an axon
- Nodes of Ranvier - in the myelin covering
- Saltatory conduction - allows for faster conduction of a nerve impulse because impulses jump from node to node
- Unmyelinated neurons - do not have the myelin sheath and use continuous conduction
- Continuous conduction - slower conduction of the nerve impulse because it must travel down the entire length of the neurone
3
Q
REFLEX ARC
A
- A reflex action is an automatic response to a stimulus
- A reflex arc describes the pathway of an electrical impulse in response to a stimulus;
- A relay neurone are found in the spinal cord, connecting sensory neurone to motor neurone;
- Neurone do not connect directly with each other: there is a gap called a synapse.
- The sequence of events is - stimulus (pain point) - receptors (pain receptors skin) - coordinators (spinal cord) - effector (muscle) - response (contraction of muscle)
4
Q
RECEPTORS
NEURONE
A
a basic structural and functional unit of the nervous system
5
Q
RECEPTORS
MULTIPOLAR
A
- one axon
- multiple dendrites extending from cell body
- most common, in brain and spinal cord
- motor neurones
6
Q
RECEPTORS
BIPOLAR
A
- one axon
- one dendrite
- branches at both ends
- occur in eye, ears, nose
- take impulses from receptors to other neurone
7
Q
RECEPTORS
UNIPOLAR
A
- one extension, and axon
- cell body to one side of the axon
- sensory neurones, bring impulse to spine
8
Q
BRAIN
CEREBRUM
A
- balance
- posture
- cardiac, respiratory , and vasomotor centres
9
Q
BRAIN
CORPUS CALLOSUM
A
communication between the left and right side of the brain
10
Q
BRAIN
HYPOTHALAMUS
A
- Moods and motivation
- Sexual maturation
- Temperature regulation
- Hormonal body processes
11
Q
BRAIN
PITURITY GLAND
A
- Hormonal body processes
- Physical maturation
- Growth (height and form)
- Sexual maturation
- Sexual functioning
12
Q
BRAIN
MEDULLA OBLONGATA
A
- Controls heartbeat and breathing
13
Q
BRAIN
CEREBELLUM
A
- Balance
- Posture
- Cardiac, respiratory, and vasomotor centres
14
Q
BRAIN
BRAIN STEM
A
- Motor and sensory pathway to body and face
- Vital centers: cardiac, respiratory, vasomotor
15
Q
BRAIN
HIPPOCAMPUS
A
Memory
16
Q
BRAIN
THALAMUS
A
Relays messages between lower brain centers and cerebral cortex
17
Q
BRAIN
PONS
A
relays information between the cerebrum and the cerebellum, controls arousal and regulates respiration
18
Q
BRAIN
CEREBRAL CORTEX
A
- outermost layer of the cerebral hemisphere that is grey matter.
- Cortices are asymmetrical.
- Both hemispheres are able to analyse sensory data, perform memory functions, learn new information, form thoughts and make decisions.
19
Q
NEROUS SYSTEM
CENTRAL NERVOUS SYSTEM
A
- BRAIN received and processes sensory info, response, stores memories, generates thoughts
- SPINAL CORD conducts signals to and from the brain, control relfex
20
Q
NERVOUS SYSTEM
PERIPHERAL NERVOUS SYSTEM
A
- outside of the body, sensory receptors
