Intro to Urea Cycle - Video Tutorials & Practice Problems
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concept
Intro to Urea Cycle Concept 1
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Everyone in this video, we're gonna take a look at the intro to the urea cycle. Now, the urea cycle converts the toxic ammonium ion into urea for excretion into Europe. Now, here this is an energy spending pathway and because it's energy spending, we're gonna say it uses energy from the hydrolysis of A TP. If we take a look here, remember when it comes to this process, we're gonna say that the urea cycle, we're gonna say we have glutamate here which undergoes oxidated, deaminate. It's going to help to create the ammonium ion which then enters the urea cycle. We're gonna say at the end of the rhea cycle, we're gonna produce our urea, our urea molecule, which is basically a carbonyl here with NH two groups on both sides. So this is an NH two and this is an NH two, this represents aurea molecule and realize here that the urea is produced within the cytosol. So we're gonna say here the ammonium ions, they are prepared for the pathway in the mitochondrial matrix. And the cycle concludes in the cytosol producing urea, right. So we'll go in greater details. But this is a broad overview of what happens when it comes to the urea cycle, how the ammonium ion enters it. And then we are secreting urea outside in the cytosol.
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example
Intro to Urea Cycle Example 1
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Here it says, what is the source of energy that drives the urea cycle? So remember the urus cycle here, it's gonna help to convert the toxic ammonium ion into urea. It is expelled in our urine. Remember it's produced within the cytosol and it is an energy consuming energy spending pathway. And because of that, we need a source of energy. Here it happens to the hydrolysis of our A TP molecule. If we take a look here at all the options, it wouldn't be to the oxidation of electron carriers. It's not the hydrolysis of acetyl coa again, it's the hydrolysis of A TP. So C is our answer. And then here no energy is required to run the urea cycle. That is not true. It is an energy spending pathway. So it requires energy. And again, that source of energy comes to the hydrolysis of A TP.
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concept
Intro to Urea Cycle Concept 2
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When it comes to the phases of the urea cycle, we're gonna say the urea cycle takes place in two phases. Phase A is our preparation phase and phase B is our conversion phase. In the preparation phase, we convert our ammonium ions into carbon oil phosphate. Now, here this is gonna consume a TP and it uses carbon dioxide found within the mitochondrial matrix. Now, here the conversion step, it produces urea from the carbo moal phosphate as well as the aspartate molecule. This phase also consumes a TP. If we take a look here, we would have our ammonium ion and we're gonna have the injection of carbon dioxide again from the mitochondrial matrix as well as the consuming of a TP. This will help to create the carb ole phosphate group. This represents our urea cycle. Here, we're crossing the mitochondrial matrix with this orange line. We're gonna say that in phase B, we have the, we're producing urea which remember is a carbonyl with an attached to two NH two groups. And it happens because of the carbon moy phosphate as well as aspartate. And again, remember in phase B, we also have the consumption or consuming of another A TP molecule, right. So a TP energy needing pathway, this is an energy spending pathway. We require the use of A TP in order to do both phases of the urea cycle.
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example
Intro to Urea Cycle Example 2
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Here. It says which of the following statements is correct about the area cycle. Carbo oil phosphate is produced in the cytosol from oxidation of amino acids. So carbo moil phosphate is not produced in cytosol, it's produced within the mitochondrial matrix. So already we know that is incorrect. The ammonium ions from oxidated deaminate are fed directly to the urea cycle. That's wrong too. Because remember in phase A, we have preparation where we convert the ammonium ions into carbo oil phosphate. That's what goes into the urea cycle directly. The recycle produces energy in the form of A T molecules. No, both phases A and B consume A TP molecules. They don't create them here. Urea is produced from carbon oil phosphate and aspartate. This is true. So, out of all the statements within this question, only option D is the correct answer.
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Problem
Problem
Which of the following statements accurately describes the structure of urea?
A
A carbonyl group bonded to two –NH2 groups.
B
A C atom double bonded to two N atoms.
C
A carbonyl group bonded to a –CH3 group and a –NH2 group.
D
A carbonyl group bonded to two –OH groups.
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