Biology - Excretion
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I don't get what the table below is trying to get at. So, I need someone to help me interpret the data! ;p
A person's normal kidney output was measured and was 4 cm3 min-1. The effect of water, sodium chloride and anti-diuretic hormone (ADH) was investigated in the following 3 separate experiments
- 1dm3 of water given to person as a drink
-person injected with 15 sm3 of 2% sodium chloride solution
-person injected with a small amount of the hormone ADH.
The results are as follows:
Time/min Kidney output/cm3min-1
water Solution NaCl injected ADH injected
0 3.9 4.1 4.2
5 4.3 3.8 0.5
10 6.1 0.5 0.4
20 8.6 0.9 1.5
30 9.7 1.4 3.8
60 10.1 1.8 4.1
90 8.3 2.6 3.9
120 4.7 3.3 4.1
Explain the relationship between the ADH and the response to water and NaCl solution using data provided.
I do not have a single clue about this... sorry you find this too info-packed. ;p
Lastly, thank you!
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Alright. There are a few things to take note first and several questions that needs to answer.
Let us see the question again. "Explain the relationship between the ADH and the response to water and NaCl solution using data provided."
The infromation provided by the question is important. "A person's normal kidney output was measured and was 4 cm3 min-1. The effect of water, sodium chloride and anti-diuretic hormone (ADH) was investigated in the following 3 separate experiments"
Note:
1) Normal kidney output 4cm3 min-1.
2) Effects of water, ADH, and NaCl solution was investigated in 3 separate experiments.
Analyzing the data:
At 0 minute, the kidney's output were relatively around 4cm3. This is true as stated by the given information.
Next step is to roughly draw the graphs.
For the subject given just water experiment, the graphs would look like a bell if you were to draw it out. Kidney's output of water will increase over time untill it reaches peak(due to the water drank) at time 60min at 10.1cm3min-1, and slowly the output decreases.
For the subject injected with a little ADH. The graph will look like a 'U' shape, bottoming at Time 10minute. From 4.2cm3min-1 at time 0min to 0.4cm3min-1 at time 10min, this is a very rapid decrease in kidney's output at a very short time. After 10minutes, the kidney's output gradually increases its output. And by time 20min, output of the kidneys remains relatively normal (4cm3min-1).For the subject injected with 15cm3 of 2% NaCl solution. The graph will also look like a 'U' shape, bottoming at time 10min at 0.5cm3min-1. Then after some time, the kidney's output starts to increase.
A rough idea of how the graph looked like.
If you observed carefully, you will see that ADH have a more faster response as compared to NaCl and water (looking at the gradient of the graph). ADH response in a hormonal response.
How does ADH helps in reducing the kidney's output?
ADH triggers an increase in water permeability in the membrane of duct cells. ADH is secreted by the hypothalamus. When it reached the kidney in the blood, it'll attach to the receptor protein on the duct cell membranes.
It triggers the enzyme that catalyzes the production of cAMP. cAMP activates another enzyme, the enzyme will alter the structural of cell protein that forms a sort of microskeleton. The cell protein changed their shape. This allows vesicles containing the water permeable pore protein to move towards the cell membrane. The vesicles fused with the membrane, adding the pore protein. This makes the membrane more permeable to water and diffuse towards the low water potential in the medulla tissue fluid. -
I also blur in ths topic, but hope this help,
ADH helps in increasing the permubility of the cells to water, maybe more water released by the cell is needed to keep a equal water potential with the nacl solution, thus more adh is secreted as to allow more water to go out of the cell, therefore, when the concentration of nacl increases, the ADH secreted by the insets of langerhans also increase, about the data, i had seriously no idea
1000th post. :)
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About the sodium part.. I need more time.