Unit 1- Introduction to Human Physiology and Neurophysiology Flashcards
What are the characteristics of Living Organisms?
Organization Acquire Materials and Energy from Environment Grow and Develop Reproduce Respond to Stimuli Homeostatic
What are the Levels of Organization?
Atom Molecule Macromolecule Organelle Cell Tissue Organ Organ System Organism
Nutrients provide ____ for energy
Materials
Energy is….
The Capacity to do work
Work is needed to…
Maintain the organization of the cell and the organism, which is needed for growth, reproduction, and development
What is needed for chemical reactions to occur in the human body?
Oxygen, Water, and Proper Body Temperature
With proper nutrients and environment, what occurs?
Normal Growth and Development.
Life comes only from?
Life
DNA
Deoxyribonucleic Acid
Genes code for
Proteins
What is necessary for all life?
Proteins
Proteins are necessary for what type of reactions?
Metabolic reactions
Metabolism
Sum total of the chemical reactions occurring in the body cells
Stimulus
A Specific form of energy detected by receptors
What do Stimuli do?
Make an organism aware of its internal and external environments.
Receptors
Detect environmental stimuli
Integrators
receive information from receptors and determine response; integrators send information about a response to effectors.
Effectors
Generate a response to the original stimulus
Homeostasis
The maintenance of a constant internal environment within its tolerance limit.
Tolerance Limits
A Narrow range of conditions where cellular processes are able to function at a level consistent with continuation of life in response to changes in the internal and external environment
What are the 3 mechanisms involved in homeostasis?
Structural
Behavioral
Functional
Structural homeostatic maintenance
Physical features of the organism
Behavioral Homeostatic maintenance
Actions and interactions of the organism
Functional Homeostatic maintenance
Metabolism of organism (Cellular, Tissue Level, or Organ)
Homeostasis is a self-adjusting mechanism involving ______.
Feedback
Feedback Mechanisms
Occur when the response to a stimulus has an effect of some kind on the original stimulus.
Negative Feedback
When the response diminishes the original stimulus.
Example of a Negative feedback loop
Exercise creates metabolic heat which raises body temp. (stimulus), cooling mechanisms such as vasodilation and sweating (response), body temp. falls (decreasing original stimulus)
Positive Feedback
When the response enhances the original stimulus.
What type of feedback is more common?
Negative
Example of a Positive Feedback Loop?
Baby begins to suckle her mother’s nipple (stimulus), a few drops of milk are released (response), baby is encouraged and continues to suckle increasing milk released ( increasing original stimulus)
What systems control Homeostasis?
The Nervous System and the Endocrine System
What is the link between the Nervous system and the endocrine system?
The Hypothalamus
Both Homeostasis and _____ are endogenous systems responsible for maintaining the internal stability of an organism.
Allostasis
Allostasis Word Origin
Allostasis was coined similarly, from the Greek allo, which means “variable;” thus, “remaining stable by being variable
Homeostasis Word Origin
from the Greek homeo, means “same,” while stasis means “stable;” thus, “remaining stable by staying the same
Allostatic Load
It’s the price the body has to pay for either doing its job less efficiently or simply being overwhelmed by too many challenges
Allostatic Load
The physiological wear and tear on the body that results from ongoing adaptive efforts to maintain stability (homeostasis) in response to stressors
What are the 11 Organ Systems
Nervous Reproductive Nephro/Urine Skeletal Muscular Lymphatic/Immune Integumentary/Exocrine Respiratory Endocrine Digestive
What are the parts of the Central Nervous System?
Brain
Spinal Cord
What are the parts of the Peripheral Nervous System?
Nerves
Ganglia
Sensory Division
Motor Division
What makes up the Sensory Division of the Peripheral Nervous System?
Visceral Sensory Division
Somatic Sensory Division
What makes up the Motor Division of the Peripheral Nervous System?
Visceral Motor Division
Somatic Motor Division
What makes up the Visceral Motor Division of the peripheral Motor Division of the Peripheral Nervous System?
Sympathetic Division
Parasympathetic Division
What are the 3 Types of Neurons?
Sensory (Afferent)
Interneurons
Motor (Efferent)
90% of our Neurons are _______
Interneurons
What is the function of Interneurons
Process, Store, and Retrieve information
Interneurons lie between the ______ and ____ Pathways in the Central Nervous System.
Sensory
Motor
Sensory (Afferent) Neurons
Conduct signals from receptors to the CNS
Interneurons (Association Neurons)
are confined to the CNS
Motor (Efferent) Neurons
Conduct signals from the CNS to effectors such as muscles and glands.
Cell Body
Soma
Perikaryon
The structure of a Neuron includes a single, central _____ with a large _____
Nucleus
Nucleolus
The structure of a Neuron includes a cytoskeleton of ______ and _____ (bundles of actin filaments)
Microtubules
Neurofibrils
The Neuron’s cytoskeleton compartmentalizes ____ into Nissl Bodies
RER
Lipofuscin
product of breakdown of worn-out organelles – more with age
Neurons’ structure includes a vast number of ____ for receiving signals
Dendrites
Neuron structure includes a single ____ arising from a hillock for rapid conduction
Axon
What are the variations in Neural Structure?
Multipolar
Bipolar
Unipolar
Anaxonic
What are the types of Neuroglial cells?
Ogliodendrocytes
Ependymal Cells
Microglia
Astrocytes
What is the general purpose of the Nervous System?
Receive, Transmit, and Interpret Stimuli
Example of the Nervous System receiving stimuli
Eyes
Example of the nervous System Transmitting Stimuli
Sensory and Motor Nerves
Example of the Nervous System Interpreting Stimuli
Brain or Spinal Cord
Example of the Nervous System Carrying out a decision
With the Muscles of the Arm.
What is the function of Neuroglial Cells
Support, protect, and Nourish Neurons
What is the most numerous type of cells in the nervous system?
Neuroglial Cells
What is the function of astrocytes?
Processes attach to neurons and their synaptic endings.
Cover nearby capillaries and anchor neurons to them.
Take up glucose from capillaries and deliver it to neurons as lactic acid.
Needed for synapse formation within the CNS.
Form the blood brain barrier.
Control the chemical environment around neurons by regulating K+ in the ECF, and recapturing and recycling neurotransmitters.
Microglia
Monitor health of Neurons
Can differentiate to macrophages when microorganisms are present
Ependymal Cells
Line Cavities of brain and spinal cord
Form permeable barrier between CSF and Interstitial fluid of the brain
Oligodendrocytes
Form Myelin Sheath
Make up white matter in the CNS
Schwann Cells
Form Myelin Sheath in the PNS
Satellite Cells
Support Cell Bodies of neurons in the PNS
Control Extracellular Fluid around Neurons
Name the Parts of a Neuron (And be able to label them)
Dendrites Cell Body Axon Hillock Axon Axon Terminal
Function of Dendrites
To receive the Neurotransmitter (Stimuli)
Convey Local Potentials to the cell body->Axon Hillock
Function of Nucleus in the Cell Body
Interpret Stimuli and be the Biosynthetic center of the cell
Axon Hillock Function
Generate Action Potentials
The Myelin Sheath in Neurons is composed of:
the cell membrane of the cell, and the neurilemma contains cell membrane, cytosol, and organelles
Function of the Axon
Conduct Action Potentials away from the cell body
Axon Terminal Function
secrete neurotransmitter substances
What are the three types of Neurons (Structural)
Multipolar
Unipolar
Bipolar
What is the most common structure of a Neuron?
Multipolar
What is the second most common structure of a Neuron?
Unipolar
Where are Bipolar Neurons found in the body?
Nasal Mucosa and Retina of the eye
The Plasma Membrane is more permeable to ___ Ions than any other ions and molecules.
K+
K+ Ions diffuse ____ the cell (Eflux) due to its concentration gradient (Chemical force)
Out of
K+ Ions are also acted upon by a ___ Force which draws K+ back into the cell due to the charged proteins and phosphate groups in the ICF
Electrical
If the cell were only permeable to K+ Ions, the cell would be at equlibrium potential at _____
-90mV
K+ ions are moving through ____-_____ ion channels ___ of the cell
Non-Gated
Out
Na+ Ions move ___ the cell (influx) due to the concentration gradient
Into
If the cell were only permeable to Na+ ions, the equilibrium potential would be
60mV
N and K Concentrations
K+ moves out (Eflux)
Na+ moves in (Influx)
What is the Nernst Equation
Allows the theoretical membrane potential to be calculated for a particular Ion
Resting Membrane Potential of the Neuron is
-70mV