[填空题]
Creatine is a naturally occurring chemich(gvb nx 0y7-qdzj5z9al produ6njs vv kbaok*t7;4cf:s h3z822j yvvced in the body which supplies energy to muscles. It’s also avf t3s6; 7 hvcjz4 bjak8yvko2*vs:n2 supplement used widely in the fitness industry to reduce recovery times and improve athletic performance.
Creatine is broken down into creatinine which is toxic in high concentrations. A study was conducted on the effect of creatine supplementation on the creatinine concentration in the urine. Urine samples were collected from humans, and the creatinine concentration was measured.
The results from the study were used to make up corresponding creatine solutions to mimic the urine samples. These creatine solutions were then given to students to analyse. The specific gravity of each sample was measured using a hydrometer, a small graduated float used to compare the density of a liquid between two samples.
1.1.Describe the source of urea in urine.
1.2.Other than protein, state the name of one substance that can be detected in urinary tests.
1.3.High creatinine concentrations in the blood can lead to kidney failure. List two possible treatments for kidney failure.
2.Suggest a variable that would need to be controlled during the student’s experiment.
3.Suggest one advantage and one disadvantage of using model urine samples instead of human urine.
4.Calculate, as a percentage, how much greater the urine sample specific gravity with 10g of supplemental creatine intake was compared to that with 5g of supplemental intake.The percentage is %
5.Describe TWO reasons why mice were used in this experiment and not humans.
