Zoology 120: Animal Physiology Lecture 2

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of mechanoreceptors?

  • To convert chemical energy into electrical energy
  • To regulate blood pressure and CO2 concentration
  • To transmit sensory information to the CNS through voltage-gated channels
  • To detect mechanical stimuli from the environment (correct)

What happens when a stimulus binds to a receptor protein?

  • The receptor protein opens mechanically-gated channels
  • The receptor protein releases neurotransmitters into the synaptic cleft
  • The receptor protein opens voltage-gated channels
  • The receptor protein triggers the opening of ion channels (correct)

What is the term for the conversion of one form of energy into electrical energy?

  • Transmission
  • Modulation
  • Transduction (correct)
  • Integration

What type of receptors are responsible for detecting chemical stimuli?

<p>Chemoreceptors (B)</p> Signup and view all the answers

What is the term for the graded potential that occurs in response to a stimulus?

<p>Generator potential (A)</p> Signup and view all the answers

What type of channels are involved in the transmission of sensory information?

<p>All of the above (D)</p> Signup and view all the answers

What is the primary function of somesthetic receptors?

<p>To detect external stimuli perceived by the body surface (D)</p> Signup and view all the answers

What happens when Ca2+ ions enter the terminal knobs?

<p>Exocytosis of neurotransmitters occurs (B)</p> Signup and view all the answers

What determines the magnitude of a receptor potential?

<p>The intensity of the stimulus (C)</p> Signup and view all the answers

What is the result of a receptor potential of sufficient magnitude?

<p>Production of an action potential (C)</p> Signup and view all the answers

Where is the action potential propagated after it is generated?

<p>Along an afferent fiber to the CNS (D)</p> Signup and view all the answers

What type of receptors adapt rapidly to sustained stimulation?

<p>Phasic receptors (C)</p> Signup and view all the answers

What type of information is provided by interoreceptors?

<p>Information regarding the body fluids (C)</p> Signup and view all the answers

What is the classification of receptors that provide information regarding the 'classic' external sensations?

<p>Exteroreceptors (A)</p> Signup and view all the answers

What is the process by which a receptor becomes less sensitive to a stimulus over time, resulting in a decrease in the frequency of action potentials?

<p>Adaptation (C)</p> Signup and view all the answers

What is the term for the process by which a receptor becomes less responsive to a stimulus due to a decrease in the strength of the stimulus?

<p>Habituation (A)</p> Signup and view all the answers

What is the primary function of afferent input from receptors?

<p>To regulate efferent output for maintaining homeostasis (A)</p> Signup and view all the answers

What is the role of the reticular activating system in the brain stem?

<p>To facilitate cortical arousal and consciousness (D)</p> Signup and view all the answers

What is the mechanism of adaptation of Pacinian corpuscle mechanical and electrical intrinsic components?

<p>Intrinsic mechanism of adaptation (D)</p> Signup and view all the answers

What is the function of Merkel cells in the integument?

<p>Epithelial tactile cells for light touch sensation and sensation of texture (B)</p> Signup and view all the answers

What is the primary function of proprioception?

<p>Detection of motion and position (D)</p> Signup and view all the answers

What is the mechanism of adaptation of olfactory receptors?

<p>Activation of proteins that closes Ca2+ channels (A)</p> Signup and view all the answers

What is the role of the central nervous system in processing sensory information?

<p>To give rise to our perceptions of the world around us (C)</p> Signup and view all the answers

What is the function of free nerve endings in the integument?

<p>Respond to high and low temperatures, pain, itching, and tactile functions (C)</p> Signup and view all the answers

What is the function of Meissner Corpuscles?

<p>initiating impulses when deformed due to light touch or low-frequency stimuli (A)</p> Signup and view all the answers

What is the function of Pacinian Corpuscles?

<p>sensing coarse touch, pressure, and vibrations (B)</p> Signup and view all the answers

What is the function of Krause End Bulbs?

<p>sensing low frequency vibrations in penis and clitoris (D)</p> Signup and view all the answers

What is the function of Ruffini Corpuscles?

<p>stimulated by stretch or twisting in skin (A)</p> Signup and view all the answers

What is the function of Statocysts?

<p>gravity receptors (D)</p> Signup and view all the answers

What is the function of the Lateral Line System?

<p>equilibrium and navigation (D)</p> Signup and view all the answers

What is the function of the Vestibular Apparatus?

<p>spatial orientation and navigation (B)</p> Signup and view all the answers

What is the function of the Neuromast organ?

<p>part of the lateral line organs in fish (C)</p> Signup and view all the answers

What is the primary function of the otolith in invertebrates and lower vertebrates?

<p>To process sound waves from the environment (C)</p> Signup and view all the answers

What is the role of the gas bladder in fish?

<p>Initial processing of sound waves (C)</p> Signup and view all the answers

What is the function of the cilia in sensory cells in vertebrates?

<p>To generate action potentials (A)</p> Signup and view all the answers

What is the purpose of the three divisions of the ear in mammals?

<p>To locate the source of sound waves (D)</p> Signup and view all the answers

What is the role of the ossicles in the middle ear?

<p>To transmit sound waves to the inner ear (A)</p> Signup and view all the answers

What is the function of the cochlea?

<p>Where the sense organ for sound will be found (D)</p> Signup and view all the answers

What is the role of the tympanic membrane in vertebrates?

<p>Initial processing of sound in vertebrates (C)</p> Signup and view all the answers

What is the function of the Organ of Corti?

<p>Sense organ for sound (B)</p> Signup and view all the answers

What is the primary function of satellite cells in ganglia?

<p>To provide nutrition to the neurons (A)</p> Signup and view all the answers

What is characteristic of pseudounipolar neurons?

<p>They have a single process that divides into two branches (B)</p> Signup and view all the answers

What is the function of lipofuscin in ganglia?

<p>To indicate age-related cytological changes (B)</p> Signup and view all the answers

What is characteristic of autonomic ganglia?

<p>They have a less distinct capsule (A)</p> Signup and view all the answers

What is the function of the cell bodies in ganglia?

<p>To transmit signals from the CNS to effector organs (B)</p> Signup and view all the answers

What is characteristic of multipolar neurons?

<p>They have multiple dendrites and a single axon (B)</p> Signup and view all the answers

What is the purpose of the connective tissue capsule in sensory ganglia?

<p>To provide structural support to the ganglion (C)</p> Signup and view all the answers

What is characteristic of cranial ganglia?

<p>They are only found in the brain stem (B)</p> Signup and view all the answers

What is the primary function of the sympathetic nervous system in regulating blood flow?

<p>Constrict arterioles to redirect blood flow (D)</p> Signup and view all the answers

Which glands are innervated by both the sympathetic and parasympathetic nervous systems?

<p>Salivary glands (C)</p> Signup and view all the answers

What is the effect of sympathetic stimulation on salivary glands?

<p>Decreases salivary secretion (B)</p> Signup and view all the answers

What happens to blood flow in the capillaries when the arterioles constrict?

<p>Decreases (A)</p> Signup and view all the answers

What is the primary function of sweat glands during stressful situations?

<p>Regulate body temperature (A)</p> Signup and view all the answers

Which nervous system division is responsible for the 'fight or flight' response?

<p>Sympathetic nervous system (C)</p> Signup and view all the answers

What is the effect of parasympathetic stimulation on salivary glands?

<p>Increases salivary secretion (D)</p> Signup and view all the answers

What is the primary function of the arterioles in the circulatory system?

<p>Regulate blood pressure (A)</p> Signup and view all the answers

What is the primary function of afferent neurons?

<p>To inform the CNS about conditions in the external and internal environment (B)</p> Signup and view all the answers

Which of the following is a characteristic of the sympathetic nervous system?

<p>Dominating in emergency or stressful situations (C)</p> Signup and view all the answers

What is the significance of dual innervation of organs by both sympathetic and parasympathetic fibers?

<p>It enables precise control over an organ's activity (D)</p> Signup and view all the answers

Which part of the nervous system lies entirely within the wall of the digestive tract?

<p>Enteric nervous system (A)</p> Signup and view all the answers

What is the direction of travel for afferent fibers in the peripheral nervous system?

<p>From the PNS to the CNS (B)</p> Signup and view all the answers

Which organs are innervated by both sympathetic and parasympathetic fibers?

<p>Most visceral organs (B)</p> Signup and view all the answers

What is the characteristic of the parasympathetic nervous system?

<p>Producing opposite effects in a particular organ (B)</p> Signup and view all the answers

What is the significance of the sympathetic nervous system dominating in emergency or stressful situations?

<p>It prepares the body for strenuous physical activity (B)</p> Signup and view all the answers

What is the primary function of nicotinic receptors in the autonomic nervous system?

<p>To regulate the postganglionic cell bodies of all autonomic ganglia (B)</p> Signup and view all the answers

What is the effect of NE binding to an alpha receptor?

<p>Cleavage of PIP2 to IP3 and DAG (B)</p> Signup and view all the answers

What is the result of IP3 binding to a receptor in the sarcoplasmic reticulum?

<p>Opening of the Ca2+ channel (D)</p> Signup and view all the answers

What is the effect of ACh not binding to a receptor in the heart?

<p>Sympathetic domination (C)</p> Signup and view all the answers

What is the mechanism of action of Metoprolol?

<p>Blockage of β1-adrenergic receptors (A)</p> Signup and view all the answers

What is the function of Salbutamol?

<p>To dilate bronchioles (C)</p> Signup and view all the answers

What is the effect of alpha receptor activation on arterioles?

<p>Constriction of arterioles (D)</p> Signup and view all the answers

What is the role of muscarinic receptors in the autonomic nervous system?

<p>To respond to parasympathetic stimulation (B)</p> Signup and view all the answers

What is the primary function of afferent nerves in the peripheral nervous system?

<p>To send information from the internal and external environment to the CNS (C)</p> Signup and view all the answers

What type of receptors are targeted by atropine?

<p>Muscarinic receptors (C)</p> Signup and view all the answers

What is the classification of receptors that provide information regarding the body's internal environment?

<p>Visceral receptors (D)</p> Signup and view all the answers

What is the function of the cranial nerve responsible for transmitting information from the nasal cavity?

<p>Transmitting olfactory information (A)</p> Signup and view all the answers

What is the primary function of the trochlear nerve?

<p>Controlling extraocular muscles (B)</p> Signup and view all the answers

What is the term for the division of the nervous system that sends information from the CNS to the periphery?

<p>Efferent division (D)</p> Signup and view all the answers

What is the primary function of the trigeminal nerve?

<p>Transmitting sensory information from the face (B)</p> Signup and view all the answers

What is the term for the type of receptors that adapt rapidly to sustained stimulation?

<p>Phasic receptors (B)</p> Signup and view all the answers

What is the primary function of the connective tissue capsule in sensory ganglia?

<p>To serve as a covering and protect the ganglion (C)</p> Signup and view all the answers

What is characteristic of pseudounipolar neurons?

<p>Having a single process that divides into two branches (A)</p> Signup and view all the answers

What is the function of satellite cells in ganglia?

<p>To provide nutrition and support to the neurons (C)</p> Signup and view all the answers

What is characteristic of autonomic ganglia?

<p>Having multipolar neurons (A)</p> Signup and view all the answers

What is the function of lipofuscin in ganglia?

<p>To indicate age-related cytological changes (B)</p> Signup and view all the answers

What is the purpose of the cell bodies in ganglia?

<p>To integrate and process sensory information (D)</p> Signup and view all the answers

Where do the fibers of the Parasympathetic Nervous System originate from?

<p>Cranial and sacral areas of the CNS (B)</p> Signup and view all the answers

What type of fibers are longer in the Parasympathetic Nervous System?

<p>Preganglionic fibers (A)</p> Signup and view all the answers

What neurotransmitter is released by most postganglionic fibers of the Sympathetic Nervous System?

<p>Noradrenaline (norepinephrine) (B)</p> Signup and view all the answers

Which blood vessels do not receive innervation from the autonomic nervous system?

<p>Arteries and capillaries (C)</p> Signup and view all the answers

What is the exception to the general rule of dual reciprocal innervation by the two branches of the autonomic nervous system?

<p>Most arterioles and veins receive only sympathetic nerve fibers (C)</p> Signup and view all the answers

What determines the length of preganglionic fibers in the Parasympathetic Nervous System?

<p>The ganglion (B)</p> Signup and view all the answers

What is the effect of binding of NE to β1 adrenergic receptor in the heart?

<p>Increased cardiac contractile force and velocity (A)</p> Signup and view all the answers

Which part of the central nervous system exerts control over skeletal muscle activity?

<p>Spinal cord, motor regions of cortex, basal nuclei, cerebellum, and brain stem (A)</p> Signup and view all the answers

What is the effect of phosphorylation of sarcoplasmic reticulum in the heart?

<p>Release of Ca2+ ions from the sarcoplasmic reticulum (C)</p> Signup and view all the answers

What is the site of release of the neurotransmitter ACh in the neuromuscular junction?

<p>Motor neuron terminal (A)</p> Signup and view all the answers

What is the result of poliovirus infection on motor neurons?

<p>Selective destruction of motor neurons (C)</p> Signup and view all the answers

What is the role of the motor neuron in the neuromuscular junction?

<p>Final common pathway for CNS control over skeletal muscle activity (A)</p> Signup and view all the answers

What is the function of visceral afferent neurons?

<p>To transmit sensory information from internal organs to the CNS (B)</p> Signup and view all the answers

What type of receptors do atropine bind to?

<p>Muscarinic receptors (C)</p> Signup and view all the answers

Which of the following is an example of a special sense?

<p>Vision (D)</p> Signup and view all the answers

What is the term for agonists that mimic the response?

<p>Agonists (B)</p> Signup and view all the answers

How many cranial nerves are there?

<p>12 (D)</p> Signup and view all the answers

What is the function of the afferent division of the peripheral nervous system?

<p>To transmit sensory information from the environment to the CNS (C)</p> Signup and view all the answers

What is the function of alpha-1 receptors?

<p>Causing muscle contraction and vasoconstriction (B)</p> Signup and view all the answers

What is the main function of the adrenal cortex?

<p>Secreting glucocorticoids for glucose, protein, and fat metabolism (D)</p> Signup and view all the answers

What type of receptors have almost equal affinity to both norepinephrine and epinephrine?

<p>Beta-1 receptors (C)</p> Signup and view all the answers

What is the main function of beta-2 receptors?

<p>Causing muscle relaxation and vasodilation (B)</p> Signup and view all the answers

Where is norepinephrine and epinephrine released from?

<p>Adrenal medulla (C)</p> Signup and view all the answers

What is the function of phospholipase C?

<p>Cleaving phospholipids just before the phosphate group (B)</p> Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Sensory Physiology

  • Afferent nervous system: receives information from internal and external environments and sends it to the CNS
  • Types of sensors or receptors:
    • Visceral afferents: subconscious input, detecting blood pressure, CO2 concentration, etc.
    • Sensory afferents: conscious awareness, detecting somatic (body) sensations, external stimuli
  • Sensory cells:
    • Have ion channels and receptor proteins with specific modalities
    • Receive external stimuli, process information, and convert it into electrical signals
  • Transduction: conversion of one form of energy into electrical energy
  • Types of gated channels:
    • Mechanically-gated
    • Chemically-gated
    • Voltage-gated
    • Thermally-gated

Classification of Sensors or Receptors

  • Mechanoreceptors: detect physical forces, touch, and pressure
  • Chemoreceptors: detect chemicals, e.g., CO2, oxygen, and pH
  • Thermoreceptors: detect temperature
  • Photoreceptors: detect light
  • Electroreceptors: detect electrical signals
  • Magnetoreceptors: detect magnetic fields
  • Nociceptors: detect pain

Receptor Cell Physiology

  • Adaptation: intrinsic or extrinsic mechanism to adjust to sustained stimulation
  • Habituation: gradual decrease in response to repeated stimuli
  • Types of receptors:
    • Tonic receptors: do not adapt at all or adapt slowly
    • Phasic receptors: rapidly adapting receptors

Mechanoreceptors

  • Detection of physical forces, touch, and pressure
  • Types:
    • Proprioceptors: detect movement and position
    • Exteroreceptors: detect external sensations
    • Interoceptors: detect information regarding body fluids
  • Statocysts: simplest organ for equilibrium, detect gravity
  • Lateral line system: somesthetic and proprioceptive mechanoreceptor system
  • Vestibular apparatus: detects movement and position
  • Cochlea: sense organ for sound

Efferent Nervous System

  • Efferent division: sends signals from CNS to effectors (muscles, glands, etc.)
  • Sympathetic nervous system: dominates in emergency or stressful situations
  • Parasympathetic nervous system: promotes responses that conserve energy
  • Enteric nervous system: lies entirely within the wall of the digestive tract

Autonomic Neurotransmitter Receptors

  • Cholinergic receptors: nicotinic and muscarinic receptors
  • Adrenergic receptors: alpha and beta receptors
  • Agonists: mimic the response
  • Antagonists: block the response

Somatic Nervous System

  • Somatic nervous system: innervates skeletal muscle, subject to voluntary control
  • Motor neurons: final common pathway by which CNS exerts control over skeletal muscle activity
  • Neuromuscular junctions: motor end plate has no threshold potential### Autonomic Agonists and Antagonists
  • Agonists mimic the response, while antagonists block the response
  • Atropine is an example of an antagonist that binds to muscarinic receptors only

Afferent Nervous System

  • The afferent division sends information from internal and external environments to the CNS
  • Visceral afferent is the incoming pathway for information from internal viscera (organs in body cavities)
  • Sensory afferent is responsible for somatic (body sense) sensation and external environment
  • Somatic sensations include sensation arising from body surface and proprioception
  • Special senses include vision, hearing, taste, and smell

Cranial Nerves

  • There are 12 cranial nerves
  • The list of cranial nerves includes olfactory, optic, oculomotor, trigeminal, trochlear, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, and hypoglossal

Adrenal Gland

  • The adrenal gland is composed of the cortex and adrenal medulla
  • The adrenal medulla is a modified sympathetic ganglion that releases NE and E
  • The adrenal cortex secretes glucocorticoids essential for glucose, protein, and fat metabolism

Adrenergic Receptors

  • Adrenergic receptors are found on effector cell membranes and are responsible for responding to NE and E
  • Alpha (α) receptors cause muscle contraction and vasoconstriction in certain body parts
  • Alpha 1 (α1) receptors are mainly found in arterioles, causing constriction, and activate Phospholipase C
  • Alpha 2 (α2) receptors are mainly found in the smooth muscles of the digestive tract, decreasing contraction
  • Beta (β) receptors cause muscle relaxation and vasodilation in other areas
  • Beta 1 (β1) receptors use the cAMP messenger system, are mainly found in the heart, and increase heart rate and contractility
  • Beta 2 (β2) receptors are mainly found in the bronchioles, causing dilation
  • Note: 1 subscripts are excitatory, while 2 subscripts are inhibitory
  • Sensitivity of receptors: α and β neurotransmitters respond to NE, α receptors have greater sensitivity towards NE, β1 receptors have almost equal affinity to both NE and E, and β2 receptors mainly respond to E

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

More Like This

Animal Body Systems: Sensory Systems
36 questions
Biology Chapter on Sensory Systems
29 questions

Biology Chapter on Sensory Systems

CooperativeFlerovium8307 avatar
CooperativeFlerovium8307
Use Quizgecko on...
Browser
Browser