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 1
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 1
Step 1
Calculate the amount of STZ for a rat's mass
Answer
To determine the dosage of STZ for a rat weighing 230.45 g, we need to use the injection rate given: 35 mg of STZ per kg of body mass.
-
Convert the rat's weight to kilograms:
egin{align*} 230.45 ext{ g} = 0.23045 ext{ kg}
ight. ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } \ 1 ext{ kg} = 1000 ext{ g}
ight. ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } ext{ } \ ext{So, } 0.23045 ext{ kg} = \ rac{230.45}{1000} ext{ kg}
ight.
ext{ }
ext{ }
ext{ }
ext{ }
ext{ }
ext{ }
ext{ }
ext{ }
ext{ }
\
2. Calculate the dose in mg:
Dosing = 35 ext{ mg/kg}
\
Amount of STZ = 35 ext{ mg/kg} \times 0.23045 ext{ kg} = 8.08675 ext{ mg}
\
3. Convert to grams:
\
\
4. Final answer in standard form:
\
.
Step 2
Suggest and explain why STZ was injected per unit of body mass
Answer
STZ (streptozotocin) was injected per unit of body mass to ensure a consistent and accurate dosage relative to the size of each rat. This method minimizes variability in drug effects, allowing for more reliable results in the study of diabetes induction across different rats.
Step 3
Discuss the conclusion on group B rats for studying type II diabetes
Answer
The conclusion that group B rats are more suitable for studying type II diabetes stems from their high-fat diet and resulting obesity. This group's physiological conditions (such as high blood glucose concentration and insulin resistance) closely mirror the characteristics of human type II diabetes, making them ideal for research.
Additionally, the findings suggest that environmental factors, such as diet, play a significant role in the development of this type of diabetes, aligning with human cases where obesity is a prominent risk factor. Researchers can leverage this parallel to understand the mechanisms and potential treatments for type II diabetes in humans.