Nervous Systems Nervous Systems Neurons Neural Signals Action

Nervous Systems

Nervous Systems

Neurons

Neural Signals • Action Potential • Membrane Potential • Sodium-Potassium Pump vs. Resting * Potential

Threshold Potential

Resting State (1) * • Both sodium • and potassium activation gates are closed Interior of cell is negative

Depolarization State (2) * • Sodium • activation gates are opened on some channels Interior of cell becomes more positive

Rising Phase of Action Potential (3) * • Most sodium • activation gates are opened Potassium activation gates are still closed

* Falling Phase of Action Potential (4) • Inactivation • • gates on sodium channels are closes Activation gates on potassium channels are opened interior of cell becomes more negative

Undershoot (5) * • Sodium • • channels are closed Potassium channels are closing Membrane returns to its resting state

Propagation of the Action Potential • Localized event • First action • potential’s depolarization sets off second action potential Travels in one direction due to refractory ______ period

Chemical Synapse

Neurotransmitters LOW –PARKINSON’S Runner’s High – inhibit GABA, increase Dopamine HIGH - SCHIZOPHRENIA Sleep, Mood, Learning Aggression, Serial Killers Low Levels LOW - SCHIZOPHRENIA

Postsynaptic Potentials IPSP – Inhibitory Post-Synaptic Potentials EPSP – Excitatory Post-Synaptic Potentials

Postsynaptic Potentials • Subthreshold – doesn’t reach threshold Temporal Summation • _____ – two signals do not reach threshold level but occur close enough to set off action potential Spatial • _____ Summation – two signals are set off at the same time setting off an action potential • Spatial Summation with an inhibitor – doesn’t reach threshold

Vertebrate Nervous System

Vertebrate Brains

Peripheral Nervous System

Peripheral Nervous System Autonomic • ______ Nervous System regulates the internal environment (usually involuntary) Somatic • ______ Nervous System regulates the external environment (usually voluntary)

Autonomic Nervous System • Sympathetic Division – Flight or fight response • Parasympathetic Division – Rest or digest response

KNOW THIS CHART! * Autonomic Nervous System

Brain

The Brainstem • The Medulla Oblongata and the Pons controls breathing, heart rate, digestion • The Cerebellum controls coordination of movement and balance (not really part of the brain stem) *

The Midbrain • The Midbrain receives, integrates, and projects sensory information to the forebrain *

The Diencepholon • Forebrain – Epithalamus • Includes the pineal gland the choroid plexus – Thalamus • conducts information to specific areas of cerebrum Hypothalamus – _______ • produces hormones and regulates body temperature, hunger, thirst, sexual response, circadian rhythms *

The Telencepholon • Cerebrum – with cortex and corpus callosum • higher thinking *

Cerebrum (KNOW THIS FIG!)

Cerebrum

Memory • Short Term – Done in the frontal lobe • Long Term – Frontal lobes interact with the Hippocampus _____ and the Amygdala ______ to consolidate

“Brainbow” Technology • Insert genes into DNA. • When expressed, some cell types become colorful. • Can see what is connected. Used to show learning. • Can trace short-and-long range connections in brain circuits

Can measure activity in a neuron

Brain-Machine Interface Braingate Neural Interface System

Monkey using brain to move robotic arm

ersity of Pittsburgh

Nutritional Requirements • Undernourished – not enough calories • Overnourished – too many calories Malnourished • ______ – missing one or more essential nutrients

Essential Nutrients • Essential Amino Acids • Essential Fatty Acids • Essential Vitamins • Essential Minerals

Essential Amino Acids • Found in proteins – 20 different types • 8 essential in adult humans (9 infants) • all in animal proteins • vegetarians need to eat grains and beans

Histidine _____ – Essential in infants

Essential Fatty Acids • Unsaturated fatty acids – used to make phospholipids for membranes

Essential Vitamins • Fat Soluble – stored in fat D, A, K, E – ______ • Water Soluble – excreted in urine – B complex and C

Essential Minerals • Inorganic nutrients – Calcium & Phosphorous • bones – Iron • anemia – Iodine • thyroid hormones – Sodium, Chlorine, & Potassium • nerve function, water regulation

Intracellular Digestion • Inside cells • All animals • Exclusive in: – Protista – Porifera

Extracellular Digestion • Outside cells • All animals above the sponges • Two Types Gastrovascular Cavity – _________ Alimentary Canal – _________

Gastrovascular Cavity • One opening • Found in Cnidaria and Platyhelminthes

Alimentary Canal • Two openings • Allows for specialization – – – – Mouth Pharynx Esophagus Crop Gizzard Stomach Intestine Anus

Digestive Tracts • Carnivores shorter – ____ digestive system – small cecum • Herbivores Longer – ____ digestive system – large cecum