BIO 2102 EXAM 4
What is the CNS made up of?
Brain, spinal cord, interneurons
What does the CNS do?
Integrate information
The brain
All info moved through spinal chord is processed in the brain,
The brain material
White matter, grey matter, 100 billion neurons
White matter
Bundles of axon/mylen sheaths
Grey matter
Neural cell bodies (somas)
Parts of the brain
Cerebrum, Cerebelum, Pons, Medulla
Cerebrum
Thought, memory, vision, touch
Cerebelum
Motor skills
Pons
Relay info to cerebelum
Medulla
Autonomic information
Spinal Chord Function
Relay info from PNS to CNS
Spinal Chord Material
Boney vertebrae, Spinal nerve, dorsal (afferent), ventral (efferent)
Spinal Nerve
Paired peripheral nerves that rise from the spinal chord
Dorsal (Afferent) Nerves
Carries sensory info to CNS
Ventral (Efferent) Nerves
Carries motor info to CNS
PNS
Somatic Nerves, Autonomic Nerves
Somatic Nerves
Skin, muscle, etc... (Voluntary)
Autonomic Nerves
Nerves to organs (Involuntary)
PNS Process (write it out)
its worth the grade
Basics of excited cell
Stimulated cells creates action potential->Nerve cells transmit information->Muscle cell intiates contraction
Draw a neuron
Dendrites, Soma, Nucleus, Axon terminal, Axon hillock, Axon, Myelin Sheath
Dendrites
recieve information
Soma
Cell functions
Axon Hillock
Cell body ends, axon begins
Axon
projection of signal
Axon terminal
Passes signal to next dendrites
Action potential
Stimulus->Depolarization->Repolarization->Hyperpolarization
Stimulus
-70mv
Depolarization
-70 -> +40 (Na+ in)
Threshold
-55mV
Repolarization
+40 -> -70 (K+ out)
Hyperpolarization
Over regulation then goes back to baseline
Depolar/Repolar
Molecules move along their concentration gradient
Resting
Molecules move against their concentration gradient
Myelin Sheath
Prevents ions passing through to outside the axon
Multiple Sclerosis
Loss of Myelin Sheath, CNS cannot regenerate Myelin
Draw the Synaptic Process
Voltage Ca+ channel, Synaptic Vessicle, Neurotransmitter, Neurotransmitter transporter, Receptor, Post synaptic density
Excitatory Transmission
Glutamate, Dompamine, Epinephrine
Glutamate
Most abundant, memory/thinking
Glutamate Misregulation
Reduced levels = Dementia, Alzheimers, Seicures
Dopamine
Promote focus, concentration, sleep, motivation, mood
Dopamine misregulation
Reduction = Parkinsons, ADHD, BPD, schizophrenia, restless leg syndrome
Epinephrine
Stimulates fight/flight, blood pressure, heart rate, blood sugar, blood flow
Epinepherine
Excessive levels = high blood pressure/diabetes
Inhibitory Neurotransmitters
Gamma aminobytryic acid, Glycine, Seretonin
Gamma aminotryic acid
regulate brain (concentration/sleep)
Gamma aminotryic acid Misregulation
Reduction = Anxiety, depression, seizures, irritability
Glycine
Most common in Spinal Chord, metabolism, hearing, pain
Glycine Misregulation
Reduction = reduced hearing/metabolism, increased pain
Seretonin
Mood, sleep, sexuality, anxiety, apetite, pain
Seretonin Misregulation
Reduction = Seasonal depression, anxiety, depression, chronic pain, fibromyaglia
Osmolarity
Concentration of solute in a solution
Marine Environment
Animal cells are hypotonic relative to the environment, lose water and gain electrolytes
Freshwater
Animals cells are hypertonic, gain water and lose electrolytes
Terrestrial Environment
Lose water to dry air, seek electrolytes
Osmoconformers (Chondrichthyes)
Confrom to the osmolarity of the surrounding environment
Chondrichthyes
Use Urea to make blood isotonic with their environment
Tradeoff of Urea
highly toxic to cells so must regulate production with TMAOs to protect cells
Shark/Mammalian Kidneys Osmosis process
Sodium/Chloride diffuse across shark gills -> sharks excrete NaCl through rectal glands active transport to maintain low conc. in blood -> Every sodium molecule grabs 2Cl- with it,
Common Osmolarity theme
Actively established electrochemical gradient, Ions move down the gradient, Water follows
Osmoregulators (all boney fish)
maintain osmolarity that differs from surrounding environment
Marine fish Osmoregulation
Drink lots of sea water, pump out excess salts
Freshwater Fish
Limit water intake, Very diluted urine, pump in electrolytes
Osmoregulation shifts in Salmon
Prolactin/Cortisol: Kills gills and replaces depending on environment
Prolactin in Salmon
Kills saltwater cells and brings in freshwater cells
Cortisol in Salmon
Kills freshwater cells and creates saltwater cells
Physionlogical Fluids
All organisms = Intracellular fluid
Multicellular Organisms = Extracellular fluids
ECF includes
Intercital fluids, plasma
Intercital Fluids
surrounds the cells
Plasma
Makes up circulatory liquid
Waste Excretion
NH3, Urea, Uric Acid
Ammonia (NH3)
Bony Fish, Tadpole
Urea
Mammals, Chondrichthyes, Frog
Uric Acid
Reptile and Insect
Most Water Demand to the Least Water Demand
Ammonia -> Urea -> Uric Acid
Most Energy to Least Energy
Uric Acid, Urea, Ammonia
When are excretory systems function
filter fluid and get rid of waste without wasting water
Excretory Structures
Metanephridia, Protonephridia
Metanephredia
Rely on hydorstatic pressure to force fluid through a filtering capsule, Includes secretion and reabsorption, Funnel like, two openings, Most protostomes/dueterostomes
Protonephridia
Rely on cillia to force fluids through, One opening, reabsorption and excretion, rotifers/flatworms/some protosomes, Urine exits through the body through nephridiopores
Malpighian Tubules (specialized metanephridia)
Found in some arthropods, Tubules closed at one end and bathed in Hemolymph, Nitrogenous waste passed from hemolymph into M.T. forming "pre-urine"
Hemolymph
Fluid equivalent to blood in arthropods
Vertebrate Filtration
Kidney and Nephron
Kidney
Organ that filters the blood, produces urine and involved in secreting hormones
Nephron
Functional Unit of the kidney that filters blood and concentrates salts to produce urine
Draw the Anatomy of the kidney
Capilary blood cells, Cortex, Medulla, Ureter
Cortex
Where most nephrons are located
Medulla
Collection Site/Reabsorption (Na+/Cl-/H2O)
Ureter
Connects nephron to the bladder
Draw the Anatomy of the Nephron
Glomerulus, Bowmans Capsule, Proximal Tubule, Decending Tubule
Renal Corpuscle
Blood fills bowmans capsule through small pores, Plasma filtered 60x a day
Proximal Tubule
Reabsorption
Ascending Tubule
Filtration of Ions
Descending Tubule
Filtration of H2O
Counter-Current Multiplier
Parallel tubes carrying fluids in the opposite directions to maximize transfer of soluble substances between tubules
Draw anatomy of renal Corpuscle
Glomerulus, Bowmans Capsule, Cells
Antidiuretic Hormone
Increases the absoroption in tissues surrounding collection ducts (released by pituitary gland), in response to water levels detected by hypothalumus
Too little water
Hypothalumus detects (sensor/integrator) -> Pituitary gland releases ADH (effector) -> Kidneys maintain blood water level -> Less water is lost in urine (urine is more concentrated) -> Blood water level returns to normal
Aldosterone
Hormone that increases sodium absorption in response to changes in blood pressure or blood volume