| Date | November 2019 | Marks available | 2 | Reference code | 19N.3.HL:.tz0.14 |
| Level | Higher Level | Paper | Paper 3 | Time zone | time zone 0 |
| Command term | Explain | Question number | 14 | Adapted from | N/A |
Question
Define glycemic index (GI).
Explain glycogen use in type I and type II muscle fibres during exercise at low and high intensities.
Discuss the location and role of GLUT4 transporters in glucose uptake into a cell.
Markscheme
glycemic index (GI) is the ranking system for carbohydrates based on the immediate effect of the food on blood glucose concentrations <when compared with a reference food such as pure glucose> ✔
low-intensity exercise predominantly uses slow-twitch muscle fibres / less glycogen ✔
high-intensity exercise predominantly uses fast-twitch/type II muscle fibres / more glycogen ✔
Location: Sub max [1]
located in muscle fibres ✔
stored inside intracellular vesicles that are translocated to the cell membrane ✔
Role:
facilitates glucose uptake ✔
allows for greater glucose movement into the cell <than GLUT1> ✔
