Date | November 2016 | Marks available | 2 | Reference code | 16N.3.SL.TZ0.6 |
Level | Standard level | Paper | Paper 3 | Time zone | TZ0 / no time zone |
Command term | Explain | Question number | 6 | Adapted from | N/A |
Question
The images show the brains of human (Homo sapiens) and baboon (Papio hamadryas). The images are not drawn to scale.
(i) Identify the structure labelled X.
(ii) Outline the function of X in the human brain
With reference to structures visible in the diagrams, explain how the human brain is more evolved for higher order functions than the baboon brain.
Markscheme
(i) cerebellum
(ii)
a. coordinates the actions of muscles
OR
motor control
b. important in balance/movement/muscle tone/posture
Do not allow ECF.
a. «higher order functions are» controlled by the cerebral hemispheres
b. the human brain has more folding of the (cerebral) cortex than the baboon brain
c. «folding» allows for more surface area / more synapses
d. «more cerebral cortex» without increasing cranium size
e. frontal lobe is larger proportion in the human brain than in the baboon brain
Do not allow answers relating to size as diagrams are not to scale and size is not “visible”.
Do not accept cerebellum unless a higher order function is given.