Biol 235 Week 3

Front 1

Describe 2 types of mass movements of liquids and solids.

Back 1

-endocytosis: into cell ie. Phagocytosis
-exocytosis: out of cell

Front 2

What is a gated channel and how does it open?

Back 2

-a type of transport protein
-voltage gated channels
-ligand gated channels
-mechanically gated channels

Front 3

Describe 3 types of pressure exerted by liquids.

Back 3

-osmotic pressure
-colloid osmotic pressure: increased inside pressure of a closed unit due to hypertonicity ie. Blood vessels
-hydrostatic pressure: pressure of fluid pushing on walls of container

Front 4

Define equilibrium potential.

Back 4

-electrical gradient opposing ion concentration gradient (charged difference between in and out)

Front 5

Define electrochemical gradient.

Back 5

-concentration of electrical and chemical gradient

Front 6

What is concentration gradient measured in?

Back 6

M or mMoles

Front 7

What is membrane potential measured in?

Back 7

Volts or mVolts

Front 8

Describe the systems involved in control pathways.

Back 8

-simple endocrine reflex
-simple nervous reflex
-complex neuroendocrine reflex

Front 9

What are the major methods of cell-cell communication?

Back 9

-gap junctions
-contact dependent signals
-local communication
-long-distance communication (with electrical or chemical signals)

Front 10

What are paracrines and autocrines?

Back 10

-paracrines: acts on different cells ie. Histamine
-autocrines: acts on same cells

Front 11

Define signal transduction.

Back 11

-Conversion of one form of signal to a different form
-signal "leading across" membrane

Front 12

What is involved in all signal pathways?

Back 12

1) ligand
2) receptor (can be inside cell also)
3) intracellular signal molecules (transduction)
4) target protein --> response

Front 13

What molecule involves ATP in signal transduction?

Back 13

-protein kinase: adds phosphate
-phospatase: removes phosphate

Front 14

What is a 1st and 2nd messenger in a signal pathway?

Back 14

-1st messenger: originates outside, ligand
-2nd messenger: within cell , part of signal transduction, ie cyclic AMP

Front 15

What ion is commonly used as a intracellular signal and what is it involved in?

Back 15

-Ca 2+ ions
-activates proteins ie calmodulin
-muscle contraction
-triggers excocytosis
-opens ion channels
-fertilization

Front 16

What are the anatomical divisions of the nervous system?

Back 16

-central nervous system: spine and brain
-peripheral nervous system: nerves (spinal and cranial)

Front 17

Describe the functional divisions of the nervous system.

Back 17

-CNS divided into afferent (sensory receptors) and efferent (motor pathways)
-efferent pathways divided into somatic (voluntary) and autonomic (parasympathetic and sympathetic)

Front 18

What Re the cell types of the nervous system?

Back 18

-neurons which carry nerve Impulses
-glial cells which support and help neurons

Front 19

Name the structural parts of a neuron beginning where a signal starts.

Back 19

-dendrites, cell body, nucleus, axon hillocks, axon, myelin sheath, axon terminals

Front 20

Name the 3 functional types of neurons.

Back 20

-sensory
-interneuron
-motor (efferent)

Front 21

Name the 6 glial cells and their function.

Back 21

-PNS: -satellite cell: chemically support cell bodies - Schwann cells: forms myelin sheaths
-CNS: - oligodendrocytes: forms myelin sheaths -astrocytes: maintains BBB, supports neurons -microglia: immunity -ependymal cells: creates cerebrospinal fluid

Front 22

Describe resting membrane potential.

Back 22

-about -70 mV
-defined as the difference of charge across the membrane at rest
-Na+, K+, Cl-, A-(large negatively charged proteins)

Front 23

Define polarization.

Back 23

-processing of opposing charges

Front 24

Define threshold potential.

Back 24

-amount of depolarization needed to create an action potential

Front 25

Define graded potential.

Back 25

-polarization that does not reach threshold potential

Front 26

What can cause a graded potential?

Back 26

-current leak
-cytoplasmic resistance: ions don't reach "trigger zone"

Front 27

Describe the phases of an action potential.

Back 27

1) resting state
2) depolarization: Na+ flows in
3) rise of action potential
4) fall of action potential (depolarization) K+ flows in
5) undershoot

Front 28

Define action potential propagation.

Back 28

-directional depolarization and repolarization across axon

Front 29

Describe the factors affecting the speed of action potential.

Back 29

-diameter of axon increases, speed AP increases
-amount of current leak increases, speed decreases
-myelin presence increases speed

Front 30

Name the space on the axon myelin sheaths create and the action of action potential jumping from these spaces.

Back 30

-node of Ranvier
-saltatory conduction

Front 31

Define spatial summation.

Back 31

Creation of an action potential through the collection of multiple graded potential from different axon terminals

Front 32

Define temporal summation.

Back 32

Creation of an action potential through the collection of multiple graded potentials from the same axon terminal.

Front 33

What is the location called where one neuron stimulates another neuron?

Back 33

Synapse

Front 34

Describe the stages of neuron-neuron transmission.

Back 34

1) AP depolarizes axon terminal
2) depolarization opens voltage gated Ca channels, Ca flows in
3) Ca triggers exocytosis of synaptic vesicle contents
4) neurotransmitters diffuses across synaptic cleft and bonds to postsynaptic cell

Front 35

How is a signal stopped?

Back 35

-diffusion of neurotransmitter
-inactivation of neurotransmitter
-transport of neurotransmitter