Neural Control & Co-ordination

Flashcards covering the anatomy of the human nervous system, neural impulse generation, synapse types, and parts of the brain based on lecture notes.

How do the endocrine and neural systems differ in terms of communication speed?

The endocrine system provides slow communication via hormones, while the neural system provides fast communication via neurons.

What is the functional difference between afferent and efferent nerves?

Afferent nerves conduct signals from sensory organs to the CNS, while efferent nerves conduct signals from the CNS to effector organs.

What are the targets of the somatic and autonomic nervous systems?

The somatic system conducts signals from the CNS to skeletal muscles (voluntary), while the autonomic system conducts signals from the CNS to smooth muscles (involuntary).

What is the first organism mentioned to have a basic neural system?

Hydra, an invertebrate in the phylum Coelenterata.

What terms describe a collection of cell bodies in the CNS compared to the PNS?

A collection of cell bodies is known as nuclei in the CNS and a ganglion in the PNS.

What terms describe a collection of axons in the CNS compared to the PNS?

A collection of axons is known as a tract in the CNS and a nerve in the PNS.

What are the four types of neurons based on the number of dendrites and axons?

Unipolar (single extension, no dendrites), Bipolar (one dendrite and one axon), Multipolar (multiple dendrites and one axon), and Pseudounipolar (single extension that later divides).

What is the definition and composition of Nissl granules?

Nissl granules are found in the cell body (cyton) of a neuron and are composed of RER + Ribosomes.

What are the three main factors responsible for the polarized state (RMP) of a neuron?

a) The $Na^+/K^+$ ATPase pump ($3 \text{ } Na^+$ out, $2 \text{ } K^+$ in); b) Leaky channels that are more permeable to $K^+$; c) Negatively charged proteins in the axoplasm.

What is the typical value for the Resting Membrane Potential (RMP)?

$$-70 \text{ } mV$$

What is the threshold stimulus required to trigger an action potential?

The minimum stimulus should reach $-55 \text{ } mV$ to $-60 \text{ } mV$.

During hyperpolarization, what is the membrane potential?

$$-90 \text{ } mV$$

What is saltatory conduction and where does it occur?

Saltatory conduction is the faster, jumping conduction of an impulse that occurs across the Nodes of Ranvier in myelinated neurons.

How do electrical synapses differ from chemical synapses in terms of communication direction?

Electrical synapses allow for bidirectional communication, while chemical synapses allow for unidirectional communication.

Provide examples of inhibitory neurotransmitters mentioned in the notes.

Dopamine, GABA, and Serotonin.

Name the three layers of the cranial meninges from innermost to outermost.

Pia mater (innermost), Arachnoid (middle), and Dura mater (outermost).

What is the function of the corpus callosum?

It is a tract of nerve fibres that connects the two cerebral hemispheres.

Which part of the brain is the 'relay centre' for sensory information?

Thalamus.

What are the primary functions of the hypothalamus?

It controls hunger (satiety centre), thirst, reproduction, various human emotions, and thermoregulation.

What structures are located on the dorsal side of the midbrain?

Corpora Quadrigemina (4 swellings).

What are the two major centers located in the Pons?

The Pneumotaxic Centre which controls respiration, and neurons that interconnect different regions of the brain.

What are the primary functions of the cerebellum?

Maintains body balance, postue, and coordinates muscle movements.

Which brain structure controls the gastric reflex and vomiting reflex?

Medulla oblongata.

What components make up the brain stem?

Midbrain + Pons + Medulla.