Tags |
|
|
Links |
|
|
Answer Upon - Biology Experiments for Teachers - Enzymes: Catalase
A domain, or a domain name, to put it more appropriately, is the URL address of a particular website. Online users will type this address in their browser window?s navigation bar. Whenever the address is keyed in and the search is initiated, the computer searches through the global domain name system (DNS). The DNS guarantees that all URL addresses are unique. When the DNS is found, the corresponding IP address for that domain name is sent back to the browser to retrieve the webpage from the host.Domain names are not necessarily required. If you are comfortable that your site is identified by a numeric IP address, then you do not need to register for a domain name. However
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficient
Picture for a moment the lion as he comes across a herd of delectable gazelle in the savannah. The lion circles his prey, crouches in the shrub, and then pounces on the unsuspecting gazelle. The lion does not go after the fastest gazelle because he knows that he will never catch it; rather, he goes for the slowest.If the goal is to catch food in order to survive, the lion was successful because he went after what he knew he could catch. The fastest of the gazelle’s is used to the advances of the lion and is quick to react. The lion knows that if he chases that prized gazelle, he will be passing up all the other gazelle in the process…so he lets it go. But in the end, even t
Outline. Catalase is an enzyme which occurs in the cells of many living organisms. Certain of the energy-releasing reactions in the cell produce hydrogen peroxide as an end-product. This compound, which is toxic to the cell, is split to water and oxygen by the action of catalase. 2H2O2 = 2H2O + O2
Samples of liver and yeast are dropped into hydrogen peroxide. Oxygen is evolved and the student is asked to extend the experiment to try and decide if an enzyme in the tissues is responsible. The experiments and the questions take about one hour.
Prior knowledge. The existence of inorganic catalysts; enzymes denatured on boiling; oxygen relights a glowing splint.
Advance preparation and materials - per group
20 volume hydrogen peroxide 50 cm3
splint
liver, about 1 cm cube
distilled water 20 cm3
dried yeast about 1 g
clean sand about 1 g
activated charcoal granules, about 1 g
Apparatus - per group
test-tube rack and 4 test-tubes
forceps or seeker for pushing liver into test-tube
4 labels or spirit marker
filter funnel
Bunsen burner
filter paper
test-tube holder
mortar and pestle
Experiment
The investigation below is a fairly critical examination of plant and animal tissues to see if they contain catalase.
(a) Label three test-tubes 1-3.
(b) Pour about 20 mm (depth) hydrogen peroxide into each tube.
(c) Cut the liver into 3 pieces.
(d) To tube 1 add a small piece of liver, and to tube 2 add a pinch of dried yeast.
(e) Insert a glowing splint into tubes 1 and 2, bringing it close to the liquid surface or into the upper part of the froth.
1 Describe what you saw happening and the effect on the glowing splint.
2 How do you interpret these observations?
3 Is there any evidence from this experiment so far, to indicate whether the gas is coming from the hydrogen peroxide or from the solid?
4 Is there any evidence at this stage that an enzyme is involved in the production of gas in this reaction?
(f) In tube 3 place a few granules of charcoal and observe the reaction.
5 Could charcoal be an enzyme? Explain your answer.
6 Assuming (i) that the gas in (f) is the same as before and (ii) that the charcoal is almost pure carbon, does the result with charcoal help you to decide on the source of the gas in this and the previous experiments?
(g) Suppose the hypothesis is advanced that there is an enzyme in the liver and yeast, which decomposes hydrogen peroxide to oxygen and water; design and carry out a control experiment to test this hypothesis.
7 Record (i) the experiment, (ii) the reasons which led you to conduct it, (iii) the observed results and (iv) your conclusions.
(h) Wash out the test-tubes. Design and carry out an experiment to see if the supposed enzyme in the plant and animal material can be extracted and still retain its properties. The experiment should include a control.
8 Describe briefly your procedure, your results and your conclusions.
9 Assuming that liver and yeast each contain an enzyme which splits hydrogen peroxide, is there any evidence to show that it is the same enzyme? What would have to be done to find this out for certain?
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficientl
Find Naturopathic Universities in the United States and Canada. If you are serious about becoming a natural healthcare provider and are attracted to naturopathic medicine, then applying to one of several naturopathic universities or schools may grant you the educational opportunity to become a practicing Naturopathic Doctor (ND).As with any educational program, it is always imperative to examine necessary prerequisites. At naturopathic universities, this is no exception. In many cases, naturopathic universities require applicants to have achieved a minimum of a 4-year degree, as well as prescribed coursework required for entrance.Today, naturopathic universities e
Advance preparation and materials - per group
20 volume hydrogen peroxide 50 cm3
splint
liver, about 1 cm cube
distilled water 20 cm3
dried yeast about 1 g
clean sand about 1 g
activated charcoal granules, about 1 g
Apparatus - per group
test-tube rack and 4 test-tubes
forceps or seeker for pushing liver into test-tube
4 labels or spirit marker
filter funnel
Bunsen burner
filter paper
test-tube holder
mortar and pestle
Experiment
The investigation below is a fairly critical examination of plant and animal tissues to see if they contain catalase.
(a) Label three test-tubes 1-3.
(b) Pour about 20 mm (depth) hydrogen peroxide into each tube.
(c) Cut the liver into 3 pieces.
(d) To tube 1 add a small piece of liver, and to tube 2 add a pinch of dried yeast.
(e) Insert a glowing splint into tubes 1 and 2, bringing it close to the liquid surface or into the upper part of the froth.
1 Describe what you saw happening and the effect on the glowing splint.
2 How do you interpret these observations?
3 Is there any evidence from this experiment so far, to indicate whether the gas is coming from the hydrogen peroxide or from the solid?
4 Is there any evidence at this stage that an enzyme is involved in the production of gas in this reaction?
(f) In tube 3 place a few granules of charcoal and observe the reaction.
5 Could charcoal be an enzyme? Explain your answer.
6 Assuming (i) that the gas in (f) is the same as before and (ii) that the charcoal is almost pure carbon, does the result with charcoal help you to decide on the source of the gas in this and the previous experiments?
(g) Suppose the hypothesis is advanced that there is an enzyme in the liver and yeast, which decomposes hydrogen peroxide to oxygen and water; design and carry out a control experiment to test this hypothesis.
7 Record (i) the experiment, (ii) the reasons which led you to conduct it, (iii) the observed results and (iv) your conclusions.
(h) Wash out the test-tubes. Design and carry out an experiment to see if the supposed enzyme in the plant and animal material can be extracted and still retain its properties. The experiment should include a control.
8 Describe briefly your procedure, your results and your conclusions.
9 Assuming that liver and yeast each contain an enzyme which splits hydrogen peroxide, is there any evidence to show that it is the same enzyme? What would have to be done to find this out for certain?
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficient
Creating Good Energy in Your Home for the HolidaysAhh, the holidays... Full of sparkle and promise of good times and wonderful foods, gifts, and tension? Yes, unfortunately, when you put a large group of people together and tie them up with a red ribbon of high expectations, you have the makings of prickly feelings, and sometimes, people get hurt or upset.And even as much as we look forward to holidays, they are sometimes full of tension because friends and relatives who may not get a long or haven't seen each other in a while are placed together. Get togethers can also sometimes magnify behaviors that aren't always positive, too. So, while holidays can be wonderf
(c) Cut the liver into 3 pieces.
(d) To tube 1 add a small piece of liver, and to tube 2 add a pinch of dried yeast.
(e) Insert a glowing splint into tubes 1 and 2, bringing it close to the liquid surface or into the upper part of the froth.
1 Describe what you saw happening and the effect on the glowing splint.
2 How do you interpret these observations?
3 Is there any evidence from this experiment so far, to indicate whether the gas is coming from the hydrogen peroxide or from the solid?
4 Is there any evidence at this stage that an enzyme is involved in the production of gas in this reaction?
(f) In tube 3 place a few granules of charcoal and observe the reaction.
5 Could charcoal be an enzyme? Explain your answer.
6 Assuming (i) that the gas in (f) is the same as before and (ii) that the charcoal is almost pure carbon, does the result with charcoal help you to decide on the source of the gas in this and the previous experiments?
(g) Suppose the hypothesis is advanced that there is an enzyme in the liver and yeast, which decomposes hydrogen peroxide to oxygen and water; design and carry out a control experiment to test this hypothesis.
7 Record (i) the experiment, (ii) the reasons which led you to conduct it, (iii) the observed results and (iv) your conclusions.
(h) Wash out the test-tubes. Design and carry out an experiment to see if the supposed enzyme in the plant and animal material can be extracted and still retain its properties. The experiment should include a control.
8 Describe briefly your procedure, your results and your conclusions.
9 Assuming that liver and yeast each contain an enzyme which splits hydrogen peroxide, is there any evidence to show that it is the same enzyme? What would have to be done to find this out for certain?
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficient
Most of us want a good credit report to obtain automobile financing, credit cards, and to purchase a home. But, beyond these consumer loans, your credit report can cost you in everyday living expenses. What you don't know about your credit could be costing you money.Having a credit card means that you can order tickets, rent a car, and reserve hotel rooms. Besides these conveniences, your credit report can mean that you must pay higher deposits and fees for everyday services.Did you know that your credit history can keep you from getting utility connections, good telephone rates, the best auto insurance, home owner’s insurance, or even keep you from getting hired?ost pure carbon, does the result with charcoal help you to decide on the source of the gas in this and the previous experiments?
(g) Suppose the hypothesis is advanced that there is an enzyme in the liver and yeast, which decomposes hydrogen peroxide to oxygen and water; design and carry out a control experiment to test this hypothesis.
7 Record (i) the experiment, (ii) the reasons which led you to conduct it, (iii) the observed results and (iv) your conclusions.
(h) Wash out the test-tubes. Design and carry out an experiment to see if the supposed enzyme in the plant and animal material can be extracted and still retain its properties. The experiment should include a control.
8 Describe briefly your procedure, your results and your conclusions.
9 Assuming that liver and yeast each contain an enzyme which splits hydrogen peroxide, is there any evidence to show that it is the same enzyme? What would have to be done to find this out for certain?
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficient
Gamers love a good console war, and so while waiting for the Xbox 360 vs PlayStation 3 debate to heat up, the fanboys have been warming up with the Nintendo DS vs the Sony PSP match.To date, it hasn’t been much of a contest, Sony launched its PSP in Japan, then made us in Europe wait a year to get our hands on (sound familiar?) and when it did arrive the silence of the games released was deafening.In the meantime, Nintendo launched the DS with inferior graphics and a weird control system and then promptly wiped the floor with PSP with game after game that converted both the hardcore gamers and then the mainstream with more accessible games like Nintendogs and Brain T
Discussion - answers
1 Effervescence should be observed in each case but it is more vigorous with yeast than with liver. The glowing splint should relight.
2 Oxygen is being produced.
3 There is no evidence to indicate whether the liquid or solid is giving the gas. If the students think that a solid is unlikely to give off a gas they could be reminded of marble and hydrochloric acid in which it is the solid producing the carbon dioxide. It seems less likely, however, that yeast and liver would both give off oxygen when treated with hydrogen peroxide, than that hydrogen peroxide should give oxygen when treated with diverse substances.
4 So far, there is no evidence of an enzyme being involved.
5 A gas will come off but not sufficiently rapidly to relight a glowing splint. Charcoal could not be an enzyme because (a) it is an element and (b) it has been produced by very high temperatures that would destroy enzymes.
6 Charcoal, as an element, could not be giving off oxygen. The gas must be coming from the hydrogen peroxide.
7 (i) The experiment should involve boiling the tissues and then putting them into hydrogen peroxide. (ii) If an enzyme is involved, (iii) no gas will be produced.
8 The student should grind the samples with a little sand and distilled water, filter and test the filtrate with hydrogen peroxide. Oxygen will be evolved with a vigour proportional to that witnessed when the original substances were tested.
The student should boil half of each extract and show that it loses its activity.
9 There seems no fundamental reason why yeast and liver should not have different enzymes which catalyse the decomposition of hydrogen peroxide. To be certain on this point, the enzymes would have to be extracted and their chemical composition determined.
HTTP = HTML link (for blogs, profiles,phorums):
<a href="http://www.hubyou.info/article/222805/hubyou-Biology-Experiments-for-Teachers--Enzymes-Catalase.html">Biology Experiments for Teachers - Enzymes: Catalase</a>
BB link (for phorums):
[url=http://www.hubyou.info/article/222805/hubyou-Biology-Experiments-for-Teachers--Enzymes-Catalase.html]Biology Experiments for Teachers - Enzymes: Catalase[/url]
Related Articles:
Building Your Online Business Around Your Knowledge
Mobile Phones: Status Symbol Or A Necessity?
Relationship Advice for Dating Singles
Bookmark it:
|