good bio questions

[joey2007]

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1. Which of the following situations will cause a decrease in the rate of diffusion of a substance
across a membrane?
a. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. b and c

2. Determine the osmolarity (in osmoles/L) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. ANSWER TO NEAREST TENTHS PLACE AND DO NOT INCLUDE
UNITS IN YOU ANSWER.

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
d. a and b
e. none of the above

4. Which of the following statements about the Na+/K+ pump is FALSE?
a. It transports Na+ out of the cell and K+ into the cell.
b. It is an example of an antiport co-transporter
c. It transports Na+ and K+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) ATP
e. None of the above statements are false.

5. Activation of a G protein:
a. promotes its dissociation into subunits.
b. promotes release of GDP and binding of GTP
c. increases its interaction with PKA
d. a and b​

e. a, b and c

 

[joey2007]

bump, nobody want to take this test?

 

[1stFemaleAlive]

i'm not sure of my answers anymore. I took the DAT a while back. Sorry if it's wrong. If other members can confirm my answers.

1. Which of the following situations will cause a decrease in the rate of diffusion of a substance​

across a membrane?
a. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. b and c​

2. Determine the osmolarity (in osmoles/L) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. ANSWER TO NEAREST TENTHS PLACE AND DO NOT INCLUDE
UNITS IN YOU ANSWER.​

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
d. a and b
e. none of the above​

4. Which of the following statements about the Na+/K+ pump is FALSE?
a. It transports Na+ out of the cell and K+ into the cell.
b. It is an example of an antiport co-transporter
c. It transports Na+ and K+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) ATP
e. None of the above statements are false.​

5. Activation of a G protein:
a. promotes its dissociation into subunits.
b. promotes release of GDP and binding of GTP
c. increases its interaction with PKA
d. a and b​

e. a, b and c

 

[siba]

same as 1stfemalealive. And Not sure about the last one though. Where did u get the questions from?

 

[Electrons]

1, b
2, 4./.8= .5?
3, a
4, c
5, e?

1. Which of the following situations will cause a decrease in the rate of diffusion of a substance
across a membrane?
A. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. B and c

2. Determine the osmolarity (in osmoles/l) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. Answer to nearest tenths place and do not include
units in you answer.

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
D. A and b
e. None of the above

4. Which of the following statements about the na+/k+ pump is false?
A. It transports na+ out of the cell and k+ into the cell.
B. It is an example of an antiport co-transporter
c. It transports na+ and k+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) atp
e. None of the above statements are false.

5. Activation of a g protein:
A. Promotes its dissociation into subunits.
B. Promotes release of gdp and binding of gtp
c. Increases its interaction with pka
d. A and b​

e. A, b and c ??

 

[joey2007]

from the practice test in my biology book.

Do you guys think #5 is E or D? Thanks.

 

[yakuza]

1. Which of the following situations will cause a decrease in the rate of diffusion of a substance
across a membrane?
a. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. b and c

2. Determine the osmolarity (in osmoles/L) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. ANSWER TO NEAREST TENTHS PLACE AND DO NOT INCLUDE
UNITS IN YOU ANSWER.
too lazy

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
d. a and b
e. none of the above

4. Which of the following statements about the Na+/K+ pump is FALSE?
a. It transports Na+ out of the cell and K+ into the cell.
b. It is an example of an antiport co-transporter
c. It transports Na+ and K+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) ATP
e. None of the above statements are false.

5. Activation of a G protein:
a. promotes its dissociation into subunits.
b. promotes release of GDP and binding of GTP
c. increases its interaction with PKA
d. a and b​

e. a, b and c

Are these questions straight from some bio or human phys book..? They're hard as sht

 

[keliao]

5. E

 

[utdent20]

1. Which of the following situations will cause a decrease in the rate of diffusion of a substance
across a membrane?
a. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. b and c

2. Determine the osmolarity (in osmoles/L) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. ANSWER TO NEAREST TENTHS PLACE AND DO NOT INCLUDE
UNITS IN YOU ANSWER.

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
d. a and b
e. none of the above

4. Which of the following statements about the Na+/K+ pump is FALSE?
a. It transports Na+ out of the cell and K+ into the cell.
b. It is an example of an antiport co-transporter
c. It transports Na+ and K+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) ATP
e. None of the above statements are false.

5. Activation of a G protein:
a. promotes its dissociation into subunits.
b. promotes release of GDP and binding of GTP
c. increases its interaction with PKA
d. a and b​

e. a, b and c

I don't know about these questions..they are really hard and too specific
for the BIO section on DAT

 

[angel dust]

1. Which of the following situations will cause a decrease in the rate of diffusion of a substance
across a membrane?
a. Increasing the concentration gradient of the substance
b. Increasing the effective thickness of the membrane
c. Decreasing the molecular weight of the substance
d. Increasing the surface area of the membrane
e. b and c

2. Determine the osmolarity (in osmoles/L) of the following solution and fill in your answer
below. 4 mol of sodium chloride, 0.4 mol of glucose and 1 mol of potassium chloride are
dissolved in 800 ml. ANSWER TO NEAREST TENTHS PLACE AND DO NOT INCLUDE
UNITS IN YOU ANSWER.

3. Which of the following comparisons regarding ion channels and carrier proteins is true?
a. Channel proteins are capable of considerably higher rates of transport
b. Both channel and carrier proteins can move molecules against their concentration
gradient
c. Channel proteins are responsible for transporting the larger molecules that carrier
proteins cannot accommodate.
d. a and b
e. none of the above

4. Which of the following statements about the Na+/K+ pump is FALSE?
a. It transports Na+ out of the cell and K+ into the cell.
b. It is an example of an antiport co-transporter
c. It transports Na+ and K+ in a 1:1 ratio.
d. It has the ability to bind and hydrolyze (cleave) ATP
e. None of the above statements are false.

5. Activation of a G protein:
a. promotes its dissociation into subunits.
b. promotes release of GDP and binding of GTP
c. increases its interaction with PKA
d. a and b[/LEFT]
e. a, b and c
​

​

what are the answers?​

 

[glk2101]

5 is E, just took a class learning about cAMP and g proteins

pka is a kinase, a g protein indirectly activates pka, which phosphorylates things

 

[marscole]

Q5 is E... PKA is protein kinase A...
G protein cascade: G protein has 3 subunits alpha beta and gamma
GDP is inactive state... translocase transfers GTP to G prot. and GDP is replaced by GTP... then G protein is activated... then... G prot. (only alpha subunit now - i believe) will bind with PKA some other sorts of cascade happens...

e.g. epinephrine and rod in our eyes...

i personally dont think you need to know all the mechanisms in details... i learned that from my grad biochem class... or indirectly, it may help you in understanding reading comprehension more easily...

ref: Principle of Biochemistry, Lehninger 4th Ed, p.436 Fig 12.12, p.459 Fig 12.34

 

[marscole]

Q3 i think it's E.

Ion channel: which is responsible to transfer specific ions from outside environment into the cells for example potassium pump... it cannot transport calcium ions into the cell so do calcium channels...

carrier protein: like carry something (specific signal) to a specific destination... for example receive a signal from the surrounding and move into nuclear membrane and activate some sort of transcription... we can find that such as e. coli... best growth environment is 37 degree C... when you switch to 42 degree C... they dont DIE... why because they produce heat resistant enzymes or proteins which make them survive....

 

[aquafreshlovin]

i get everything else except for quesiton #3. please post the answer!