2011 physiology midterm

Question 1

What is the correct sequence of homeostatic control? 
A. sensory>effector>integrating center 
B. integrating center> effector>sensory 
C. sensory>integrating center>effector 
D. effector>sensory>integrating center 
E. integrating center>sensory>effector

Answer 1

C. sensory>integrating center>effector

Question 2

What is meant by transcytosis?
A. the movement of a substance along cell layers
B. the movement of a substance across the cell
membrane to the inside
C. secretion of substances outside of the cell
D. the transport of a substance from ER to golgi
E. the transport of a substance from golgi to ER

Answer 2

A. the movement of a substance along cell layers

Question 3

What is triggered when epinephrine binds to its receptor?
A. generation of second messengers
B. dissociation of the ligand-receptor complex
C. degradation of the receptor
D. generation of first messengers

Answer 3

A. generation of second messengers

Question 4

The resting membrane potential in a nerve is -90 mV. Which of the following contributes the most to the nerve RMP?
A. Cl- equilibrium potential
B. K+ equilibrium potential
C. Na+ equilibrium potential
D. Ca++ equilibrium potential
E. Organic anions trapped inside the cell

Answer 4

B. K+ equilibrium potential

Question 5

What substrate does the G-protein bind to when it is activated?
A. tyrosine kinase
B. guanylate cyclase
C. signal transducers and activators of transcription
D. adenylyl cyclase
E. nuclear receptors

Answer 5

D. adenylyl cyclase

Question 6

A lipophilic substance crosses the cell membrane and binds to its cytosolic receptor. What will this hormone receptor complex bind to next?
A. DNA binding domain 
B. Heat shock proteins 
C. Co-repressors
D. nuclear receptors 
E. response element

Answer 6

E. response element

Question 7

By what method does calcium enter into the ER? 
A. Primary active transport
B. Secondary active transport 
C. Tertiary active transport 
D. Facilitated transport
E. Passive transport

Answer 7

A. Primary active transport

Question 8

Which of the following does not affect the diffusion rate of simple diffusion?
A. concentration gradient
B. carrier numbers
C. molecular weight
D. surface area of the membrane
E. pressure difference across the membrane

Answer 8

B. carrier numbers

Question 9

How do specific extracellular proteins enter the cell? 
A. pinocytosis
B. transcytosis
C. receptor mediated endocytosis 
D. exocytosis

Answer 9

C. receptor mediated endocytosis

Question 10

What is true about the ionic distribution between the inside and outside of the cell?
A. the concentration of K+ is higher outside than inside the cell
B. the concentration of Na+ is higher inside than outside the cell
C. Most Ca++ ions are found inside the cell
D. Most organic anions are trapped inside the cell
E. Cl- concentrations are higher inside the cell

Answer 10

D. Most organic anions are trapped inside the cell

Question 11

In homeostatic regulation of blood pressure, the cardiovascular center in the brain acts as:
A. sensor 
B. effector 
C. set point
D. efferent pathway 
E. integrating center

Answer 11

E. integrating center

Question 12

-hydrostatic capillary pressure= 30 mmHg
-tissue colloid osmotic pressure= 9 mmHg
-negative interstitial fluid pressure= 2 mmHg
-plasma colloid osmotic pressure= 30 mmHg
calculate nef force
A. 11 mmHg inward
B. 11 mmHg outward
C. 7 mmHg outward
D. 7 mmHg inward
E. 51 mmHg inward

Answer 12

B. 11 mmHg outward

Question 13

Where are most of the neurotransmitters found in the absence of the action potential?
A. in vesicles
B. in the cytoplasm
C. in the synaptic gap
D. integrated into the pre-synaptic membrane
E. bound to auto-receptors

Answer 13

A. in vesicles

Question 14

What happens when a cell is placed in a solution of 9g of NaCl in 1L of water?
A. net movement of water outside of the cell
B. net movement of water inside the cell
C. no movement of water
D. no net movement of water
E. movement of NaCl to the inside of the cell

Answer 14

D. no net movement of water

Question 15

What is the approximate resting membrane potential in myocytes with increased ADP/ATP ratio?
A. 0
B. -85 mV 
C. -95 mV 
D. +20 mV 
E. -30 mV

Answer 15

C. -95 mV

Question 16

Which event leads to an increase in the ICF volume?
A. infusion of .9% NaCl solution
B. hemorrhage
C. infusion of 400ml of 2.5% NaCl solution
D. drinking large amounts of water
E. losing more water than salt when exercising

Answer 16

D. drinking large amounts of water

Question 17

If a solution of 282 mOsm/L is separated by a semi-permeable membrane from pure water, what is the osmotic pressure?
A. 6450 
B. 4536 
C. 5431 
D. 5420 
E. 5443

Answer 17

E. 5443

Question 18

What is the electrical potential needed to maintain the K+ concentration difference when:
K+ inside= 100 K+ outside=10
A. +61 mV 
B. -61 mV 
C. +1.96 mV 
D. -90 mV 
E. -5.8 mV

Answer 18

B. -61 mV

Question 19

Which of the following leads to extracellular edema?
A. decrease in tissue pressure
B. decrease in the capillary pressure
C. decreased amount of plasma proteins 
D. increased lymph flow
E. Na/k pump defect

Answer 19

C. decreased amount of plasma proteins

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Question 20

What is the function of Golgi in the cell? 
A. sorting of proteins
B. oligomerization 
C. synthesis of lipids
D. protein degradation 
E. folding of proteins

Answer 20

A. sorting of proteins

Question 21

What mass of NaCl is required to make 1 osmolar solution of NaCl? (MWT=58.5)
A. 58.5 
B. 117 
C. 29.25 
D. 19.5
E. 14.625

Answer 21

C. 29.25

Question 22

A person has 60L TBW with 280 mOsm/L osmolarity and ICF volume of 40L. He got an infusion of 500ml 2.9% NaCl solution. What is the total number of osmoles in his body after the infusion?
A. 16900 
B. 18200 
C. 17100 
D. 17300
E. 15600

Answer 22

D. 17300

Question 23

For the same person above, what is the total osmolarity after infusion?
A. 310 
B. 285.9 
C. 420 
D. 295 
E. 277

Answer 23

B. 285.9

Question 24

A person has 40L TBW with 300 mOsm/L. He lost 1L of water due to heavy exercise. What is his new osmolarity?
A. 295
B. 280 
C. 330 
D. 410 
E. 308

Answer 24

E. 308

Question 25

Which one of the following has the most body water? 
A. a 70 year old male
B. a 70 year old female 
C. a 20 year old male 
D. a 30 year old female 
E. an 80 year old male

Answer 25

C. a 20 year old male

Question 26

Which of these connects cells? 
A. Cadherins
B. Heat shock proteins 
C. Steroids
D. Actins 
E. Fibrins

Answer 26

A. Cadherins

Question 27

Na inside= 10 Na outside= 130 
Cl inside= 6	Cl outside= 118 
K inside= 140 K outside= 4
What is the membrance potential when equal amounts of Na and Cl channels are open?
A. 1.6 
B. -1.6 
C. -5.8 
D. 5.8 
E. -17

Answer 27

A. 1.6