Homeostasis Unit

SBI4U Homeostasis Unit Test

Name: _______________________________ Date: _______________________

Instructions: You have 70 minutes to complete all test questions in the space provided.

A. Fill in the blank questions: (12 marks) – 9 minutes

1. _______________ breaks down neurotransmitters within the synapse so that the postsynaptic receptors are available for the next signal. Acetycholinesterase K/U

2. _____________ are located at one end of a neuron, they are the primary site for receiving signals from other neurons. Dendrites (K/U)

3. ___________________ is a primary neurotransmitter of the sympathetic nervous system which increases heart rate, blood pressure, and produces other “fight-or-flight” responses. Norepinephrine (K/U)

4. _____________________ are neurons located in the CNS. Interneurons (K/U)

5. During __________________ there is a facilitated diffusion of sodium ions, whereas during ________________there is a facilitated diffusion of potassium ions, of the action potential. Depolarization, Repolarization K/U

6. Molecules called _______________________ relay messages across the synaptic cleft between the two neurons. Neurotransmitters (K/U)

7. ___________________increase the speed at which action potentials travel and provide insulation to the axon. Myelin sheath (K/U)

8. Stress tends to promote _____________ activity of the sympathetic nervous system and secretion of epinephrine thereby ____________ gluconeogenesis. (T/I) increased, stimulating

9. Increased glucagon secretion will stimulate the liver to ___________________ gluconeogenesis and glycogenolysis which ultimately works to _______________ plasma glucose levels. (T/I) increase, increase

B. Multiple-Choice questions: (21 marks) K/U – 21 minutes

Use the diagram to your right to answer questions 1-3.

1. Which structure produces secretions that regulate E and H?

a) A

b) B

c) C

d) D

2. Which two...