Photo AI

Calculate how many grams of STZ should be injected into a rat with a mass of 230.45 g - AQA - A-Level Biology - Question 8 - 2022 - Paper 2

Question 8

Calculate how many grams of STZ should be injected into a rat with a mass of 230.45 g. Show your working. Give your answer in standard form.

Worked Solution & Example Answer:Calculate how many grams of STZ should be injected into a rat with a mass of 230.45 g - AQA - A-Level Biology - Question 8 - 2022 - Paper 2

Step 1

96%

114 rated

Answer

The recommended dosage of STZ is 35 mg per kg of body mass. First, convert the mass of the rat from grams to kilograms:

$230.45 ext{ g} = 0.23045 ext{ kg}$

Now, calculate the amount of STZ needed:

$ext{STZ dosage} = 35 ext{ mg/kg} \times 0.23045 ext{ kg} = 8.08 ext{ mg}$

Step 2

99%

104 rated

Answer

Since 1 gram = 1000 mg, we convert the dosage from mg to grams:

$8.08 ext{ mg} = \frac{8.08}{1000} ext{ g} = 0.00808 ext{ g}$

To express in standard form, we write:

$0.00808 = 8.08 \times 10^{-3} ext{ g}$

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;