Study Guide 1

Front 1

Differentiate between sensation and perception.

Back 1

A sensastion is an impulse sent to the brain from activated receptors and sensory neurons.
Perception is the interpretation of sensations by the brain.

Front 2

Explain the difference between exteroreceptors and interorceptors.

Back 2

Exteror is A sensory receptor that detects stimuli outside the body, such as heat, light, pressure, and chemicals.
and interor is a sensory receptor that detects stimuli within the body, such as blood pressure and body position.

Front 3

Name the three stages in the processing of information by nervous systems

Back 3

sensory input
integration
motor output

Front 4

Explain the role of the sodium-potassium pump in maintaining the resting potential

Back 4

The sodium-potassium pump generates and maintains the ionic gradients of Na+ and K+. The pump uses ATP to actively transport Na+ out of the cell and K+ into the cell.

Front 5

Describe the characteristics of an action potential. Explain the role of voltage-gated ion channels in this process

Back 5

An action potential is a brief, all-or-none depolarization of a neuron's plasma membrane. When a graded depolarization brings the membrane potential to the threshold, many voltage-gated Na+ channels open, triggering an inflow of Na+ that rapidly brings the membrane potential to a positive value. The membrane potetial is restored to is normal resting value by an inactivation of sodium channels and by the opening of many voltage-gated potassium channels, which increases K+ outflow.

Front 6

Explain how an action potential is propagated along an axon

Back 6

An action potential travels from the axon hillock to the synaptic terminals by regenerating itself along the axon.

Front 7

Describe the factors that affect the speed of action potentials along an axon and describe the adaptation that increase the speed of propagation. Describe saltatory conduction

Back 7

The speed of conduction of an action potential increases with diameter of the axon and, in many vertebrate axons, with myelination. Action potentials in myelinated axons jump between the nodes of Ranvier, a process called saltatory conduction

Front 8

Compare an electrical synapse and a chemical synapse.

Back 8

In an electrical synapse, electrical current flows directly from one cell to another via gap junctions. In a chemical synapse, depolarization of the synaptic terminal causes synaptic vesicles to fuse with the terminal membrane and release neurotransmitter into the synaptic cleft.

Front 9

Describe the structures of a chemical synapse and explain how they transmit an action potential from one cell to another.

Back 9

When an action potential depolarizes the plasma membrane of the synaptic terminal it opens voltage-gated calcium channels in the membrane, triggering an influx of Ca 2+.

The elevated Ca 2+ concentration in the terminal causes synaptic vesicles to fuse with presynaptic membrane.

The vesicles release neurotransmitter into the synaptic cleft. Then it binds to the receptor portion of ligand-gated ion channels in the postsynaptic membrane, opening the channels.

Front 10

Explain how excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) affect the postsynaptic membrane potential.

Back 10

In EPSP depolarization bring the membrane potential toward threshold and IPSP move the membrane potential farther from threshold.

Front 11

Define summation and distinguish between temporal and spatial summation

Back 11

Summation is the total factors that add to the magnitude.
Temporal summation membrane potential of the postsynaptic cell in a chemical synapse is determined by the combined effect of EPSPs or IPSPs produced in rapid succession.

Spatial summation membrane potential of the postsynaptic cell is determined by the combined effect of EPSPs or IPSPs produced nearly simultaneously by different synapses.

Front 12

Distinguish between the functions of the autonomic nervous system and the somatic nervous system

Back 12

Autonomic nervous systems is A subdivision of the motor nervous system of vertebrates that regulates the internal environment; consists of the sympathetic, parasympathetic, and enteric divisions.

The somatic nervous system is the branch of the motor division of the vertebrate peripheral nervous system composed of motor neurons that carry signals to skeletal muscles in response to external stimuli.

Front 13

Explain the importance of sensory adaptations.

Back 13

Without sensory adaptation, you would constantly aware of feeling every beat in yor heart and every bit of clothing on your body. Adaptation also enables you to see, hear, and smell changes in environments that vary widely in stimulus intensity.

Front 14

List the five types of sensory receptors.

Back 14

Mechanoreceptors
Chemoreceptors
Electromagnetic receptors
Thermoreceptors
Pain receptors

Front 15

Explain the role of mechanoreceptors in hearing and balance

Back 15

they produce receptor potentials when paticles or moving fluid cause deflection of cell surface structures

Front 16

the structure and function of invertebrate statocysts

Back 16

A common statocyst consists of a layer of cilliated receptor cells surrounding a chamber that contains one or more statoliths, which are grains of sand or other dense granules.
The settling of statoliths to the low point in the chamber bends cilia on receptor cells in that locations, providing the brain with information about the orientaton of the body with the respect to gravity.

Front 17

Explain how the mammalian ear functions as a hearing organ

Back 17

The tympanic membrane (eardrum) transmits sound waves to three smallbones of the middle ear, which transmit the waves through the oval window to the fluid in the coiled cochlea of the inner ear. Pressure waves in the fluid vibrate the basilar membrane, depolarizing hair cells and triggering action potentials that travel via the auditory nerve to the brain. Each region of the basilar membrane vibrates most vigorously at a particular frequency and leads to excitation of a specific auditory area of the cerebral cortex

Front 18

Describe the hearing and equilibirum systems of nonmammalian vertebrates.

Back 18

The detection of water movement in fishes and aquatic amphibians is accomplished by a lateral line system containing clustered hair cells.

Front 19

Describe what happens after and odorant binds to an odorant receptor on the plasma mebrane if the olfactory cilia.

Back 19

Triggers signal transduction leading to the production of cyclic AMP. In olfactory cells, cyclic AMP opens channels in the plamsma membrane that are permeable to both Na+ and Ca 2+. The flow of these ions into the receptor cell leads to depolarization of the membrane, generating action potentials.

Front 20

Describe the function of the rod cells and cone cells of the certebrate eye

Back 20

Rods are more sensitive to light but do not distinguish colors; they enable us to see at night, but only black and white. Cones provide color vision,but, being less sensitive, contribute very little to night vision.

Front 21

Describe three functions of a skeleton

Back 21

Provides a rigid structure to which muscles can attach..

Skeletons functions in support and protection as well as movement

Front 22

Describe how hydrostatic skeletons function and explain why they are not found in large terrestrial organisms

Back 22

A hydrostatic skeleton consists of fluid held under pressure in a closed body compartment. They control their movement by using muscle to change the shape of fluid-filled comparments. They cannot support terrestrial activites in which an animals body is held off the ground, such as walking or running

Front 23

Explain how a skeleton combines with an antagonistic muscle arrangement to provide a mechanism for movement.

Back 23

They provide movement by contracting and pulling against the skeleton

Front 24

Explain how muscle contraction is controlled from an impulse to the role of Ca2+

Back 24

A motor neuron initiates contraction by releasing acetlycholine, which deploarizes the muscle fiber. Action potentials travel to the interior of the muscle fiber along the T tubules, stimulating the release of Ca 2+ from the sacroplasmic reticulum.

Front 25

Explain how the nervous system produces graded contraction of whole muscles.

Back 25

Varying the number of muscle fibers that contract and by varying the rate at which muscle fibers are stimulated.

Front 26

Explain the adaptive advantages of slow and Fast muscle fibers.

Back 26

Fast-twich fibers fatigue faster since they use glycolytic fibers and slow-twich fibers use are oxidative so they are in a use of a steady energy supply

Front 27

Distinguish among skeletal muscle, cardiac muscle, and smooth muscle.

Back 27

Skeletal muscle consists of a bundle of muscle cells (fibers), each of which contains myofibrils composed of thin filaments of actin and thick filaments of myosin.

Cardiac muscle consists of striated cells that are electrically connected by intercalated disks and that can generate action potentials without imput from neurons.

In smooth muscles, contractions are slow and may be initiated by the muscles themselves or by stimulation from neurons in the autonomic nervous system

Front 28

List the advantages associated with moving through an (A)aquatic environment (B) terrestrial environment (C) Air

Back 28

(A) Most animals are reasonably buoyant in water, overcoming gravity is less of a problem for swimming animals than for species that move on land or through air.
(B) Air poses little resistance, at moderate speeds
(C) Birds are very light

Front 29

List the disadvantage associated with moving through an (A)aquatic environment (B) terrestrial environment (C) Air

Back 29

(A) Water is much denser and more viscous medium than air, and thus friction is a major problem for aquatic animals.
(B) Animals must be able to support theirselves and move against gravity.
(C) Gravity

Front 30

Discuss the factors that affect the energy cost of locomotion.

Back 30

Animals that are specialized for swimming expend less energy per meter traveled than equivalently sized animals specialized for flying or running. In addition, larger animals are more efficient than smaller animals specialized for the same mode of locomotion