BIO SCI E109 Final

Question 1

1.1 What does the axon hillock do?

Answer 1

It serves as a spike-initiating zone because of the presence of voltage-gated channels

Question 2

1.1 What do the dendrites do?

Answer 2

It can integrate stimuli from inhibitory and excitatory synapses

Question 3

1.1 What do graded potentials do?

Answer 3

Graded potentials occur within an axon inside of a myelinating Schwann cell

Question 4

1.2 What is true about the equilibrium potential?

Answer 4

It indicates the voltage generated by a difference in ion concentration across a membrane

It varies with the valence (i.e. charge) of an ion

It depends on temperature

It indicates the membrane potential if a membrane is permeable to only one ion type

Question 5

1.4 Which of the following statements are true of molecular diffusion?

Answer 5

The rate of motion depends on temperature

Individual particles in solution move in random directions

Question 6

1.5 What is true about action potentials?

Answer 6

Voltage-gated channels for Na+ and K+ have the same threshold Vm

Depolarization would not happen if not for voltage-gated Na+ channels

Repolarization is driven by K+ permeability

Question 7

1.6 Why does a second stimulus early in the relative refractory period have to be stronger to initiate an action potential?

Answer 7

Because the membrane is hyperpolarized

Because the threshold voltage is greater

Question 8

1.7 What does homeostasis in body temperature suggest?

Answer 8

That your physiology tries to maintain body temperature against perturbations from activity

Question 9

1.8 True or False: All connective tissue includes cells

Answer 9

True

Question 10

1.9 How would the equilibrium potential for potassium (E K+) change if the concentration of that ion increased outside of a cell?

Answer 10

[K+] is greater inside the cell to create a negative equilibrium potential. Increasing potassium outside the cell creates less of a gradient, which would make the equilibrium less negative and therefore would increase in value

Question 11

1.10 Where does change conformation occur?

Answer 11

Change conformation is in carrier proteins

Question 12

1.10 What proteins allow ions to leak?

Answer 12

Channel proteins

Question 13

1.10 Where are the transmembrane proteins located?

Answer 13

Channel proteins and carrier proteins

Question 14

1.10 What tissues are NOT excitable?

Answer 14

Connective and epithelial tissues

Question 15

1.11 What tissues ARE excitable?

Answer 15

Muscle and nervous tissue

Question 16

1.13 Which of the following statements are true?

Answer 16

Connective tissues possess cells

Ground substance may be liquid

Question 17

1.13 Which of the following statements are false?

Answer 17

Muscles are one type of connective tissue. Muscles are their own type of tissue

Adipose tissue has a crystalized matrix

Question 18

1.14 True or False: Ground substance may be a liquid

Answer 18

True. Plasma is a liquid ground substance

Question 19

1.15 What channel does the excitatory synapse have?

Answer 19

Ligand-gated Na+ channel

Question 20

1.15 What channel does the inactivation gate have?

Answer 20

Voltage-gated Na+ channel

Question 21

1.15 What channel drives depolarization in the axon?

Answer 21

Voltage-gated Na+ channel

Question 22

1.15 What channel drives depolarization in the axon?

Answer 22

Voltage-gated K+ channel

Question 23

1.15 What channel does the inhibitory synapse have?

Answer 23

Ligand-gated Cl- channel

Question 24

1.16 True or False: An action potential measured at the distal end of an axon is identical to one measured at the spike-initiating zone

Answer 24

True

Question 25

1.16 True or False: All action potentials show the same maximum depolarization

Answer 25

True

Question 26

1.16 True or False: Action potentials travel in 2 directions routinely

Answer 26

False

Question 27

1.16 True or False: The maximum depolarization of an action potential depends on the graded potential at the spike-initiating zone

Answer 27

False

Question 28

1.17 Which of the following ARE/ARE NOT a type of connective tissue?

Answer 28

ARE: Adipose, tendon, and bone

ARE NOT: Epithelium