A-Level Edexcel Biology A2 Substitution into Equations

A-Level Edexcel Biology A2 Substitution into Equations
Pearson Edexcel International Advanced Subsidiary/Advanced Level in Biology, Issue 2, February 2021Biology XBI11/YBI11

Review A-Level Edexcel Biology substitution into algebraic equations through MAP, enzyme-rate, cardiac-index and BMI calculations from graphs or tables.

How this is tested

  • substitute graph or table values into MAP, rate, cardiac index and BMI formulae
  • state or derive biological calculation units such as cardiac index units
  • calculate missing biological quantities after substituting values into supplied equations

Question 6(b)(ii)

[Maximum number: 3]

The human body responds to changes in both its internal and external environments.

The heart responds to adrenaline by increasing cardiac output.

Cardiac output = heart rate × stroke volume

The formula shows how to calculate the cardiac index. This is a method of adjusting cardiac output values for the body surface area of an individual.

 cardiac index = cardiac output in dm3 min−1 body surface area in m2\text { cardiac index }=\frac{\text { cardiac output in } \mathrm{dm}^{3} \mathrm{~min}^{-1}}{\text { body surface area in } \mathrm{m}^{2}}

The table shows some information for cardiac output, body surface area and cardiac index for two individuals.

Table for Question 6(b)(ii) — Edexcel A-Level Biology A2

Complete the table to show the units for cardiac index, the cardiac index for individual A and the cardiac output for individual B .