A-Level AQA Biology Biological Molecules: Carbohydrates: Alport syndrome (AS) is an inher

Question

Alport syndrome (AS) is an inherited disorder that affects kidney glomeruli of both men and women. Affected individuals have proteinuria (high quantities of protein in their urine).

1. Suggest how AS could cause proteinuria.

2. AS results from a sex-linked mutation.
In a male with AS, where would the sex-linked mutation be located? Tick (✓) one box.
- The homologous section of a Y chromosome
- The homologous section of an X chromosome
- The non-homologous section of a Y chromosome
- The non-homologous section of an X chromosome

Scientists investigated the use of transplanted stem cells to treat AS in mice.

Group A – 40 wild type* mice
Group B – 40 AS mice
Group C – 40 AS mice that received stem cells from AS mice
Group D – 40 AS mice that received stem cells from wild type mice

*Wild type mice are not affected by AS.

After 20 weeks, the scientists measured the quantity of protein in the urine using a scale from 0 (lowest quantity) to +++++ (highest quantity).

The results the scientists obtained are shown in Table 2.

Table 2

| Group | Maximum quantity of protein in urine at 20 weeks | Percentage of mice with this quantity of protein |
|-------|--------------------------------------------------|-----------------------------------------------|
| A     | 0                                                | 97.5                                          |
| B     | ++++                                            | 100                                           |
| C     | ++++                                            | 68                                            |
| D     | ++                                              | 68                                            |

3. Using all the information, evaluate the use of stem cells to treat AS in humans.

4. The scientists carried out further work to investigate how the transplanted stem cells developed after transplantation.

- The scientists transplanted stem cells from wild type male mice into AS female mice.
- After 20 weeks, they found that the quantity of protein in the urine of these female mice had significantly decreased.
- They examined cells from glomeruli in the female mice. Some of these cells contained a Y chromosome.

Suggest how the transplanted stem cells reduce proteinuria.

Alport syndrome (AS) is an inherited disorder that affects kidney glomeruli of both men and women - AQA - A-Level Biology - Question 8 - 2020 - Paper 2

Worked Solution & Example Answer:Alport syndrome (AS) is an inherited disorder that affects kidney glomeruli of both men and women - AQA - A-Level Biology - Question 8 - 2020 - Paper 2

Suggest how AS could cause proteinuria.

In a male with AS, where would the sex-linked mutation be located? Tick (✓) one box.

Using all the information, evaluate the use of stem cells to treat AS in humans.

Suggest how the transplanted stem cells reduce proteinuria.

Join the A-Level students using SimpleStudy...