Answers, BIO 2310, Brain and Cranial Nerves


1. Meninges – specifically dura mater, arachnoid, pia mater

2. Ventricles are cavities in the brain. The cerebrum has the lateral ventricles, the diencephalon has the third ventricles and the brainstem has the fourth ventricle

3. The lateral and third ventricles connect through the interventricular foramen, the third and fourth ventricles connect through the cerebral aqueduct.

4. Formed from blood in the choroid plexus which line the ventricles – especially in the lateral ventricles. It circulates as described in number 3 and then in the subarachnoid space of brain & spinal cord.

5. Cushion, nourishment and transport of nutrients/waste

6. Cerebrum, cerebellum, brainstem and diencephalon

7. Medulla oblongata is most inferior, pons is just above it and mesencephalon is above the pons


9. At the pyramids the pathways (both motor and sensory) cross to the other side of the body.

10. Connects brain and spinal cord, vital functions are controlled here such as breathing, blood pressure and heart functions, houses the reticular activating system which causes you to be awake when stimulated, and coordinates other reflexes such as swallowing, vomiting…

11. Controls consciousness and sleep.

12. Bridges the parts of the brain – e.g. cerebellum and medulla. Also helps regulate breathing.

13. Cerebral peduncles are important centers for descending motor pathways. Superior colliculi are responsible for visual reflexes and inferior colliculi are responsible for auditory reflexes.

14. Thalamus is superior to mesencephalon and is the main sensory relay center. All sensory information passes through the thalamus except smell. Thalamus send the important sensory information along to the cerebrum, but stops unimportant sensory information. The hypothalamus is just below the thalamus. It is the center for homeostasis activities such as hunger, thirst, temperature, it regulates the autonomic nervous system, is responsible for emotions such as rage and makes some important hormones.

15. Cerebrum

16. Gray matter (outer cerebrum) of cerebrum.

17. A gyrus or a convolution is the bump or fold of the cerebrum. The sulcus is the dip between the convolutions and a fissure is a big dip.

18. Temporal, Frontal, Parietal and Occipital

19. Commissural fibers (primarily the corpus callosum) go from one hemisphere to the other; association fibers interconnect within a lobe of the cerebrum and projection fibers are the ascending sensory pathways and the descending motor pathways.

20. Longitudinal fissure. They are internally connected by the corpus callosum.

21. Cerebral cortex, Basal nuclei which “fine tunes” motor activity.

22. Motor (voluntary movement), Premotor (repetitive, stereotyped movement), motor speech area (talking) are in the frontal lobe.

General sensory, taste are in the parietal lobe.

Hearing and Olfaction are in the temporal lobe.

Vision is in the occipital lobe.

Association areas responsible for intelligence and thought are throughout all lobes.

23. Smoothing out motor activity

24. Cerebrum and diencephalon. Responsible for emotions related to survival such as finding sex pleasurable relates to the survival of humans.

25. Generally, left brain controls right hand, speech and analytical skills; right brain controls artistic abilities, thinking in 3-D and left hand.

26. Location is inferior & posterior brain and it is control of coordination and equilibrium. The transverse fissure separates it from cerebrum.

27. Nerve going to or from brain, mixed contains both sensory and motor info. They are all mixed except I, II, VIII.

28. See cranial nerve page.

29. Ascending and crosses to the other side at the pyramids.

30. Descending. If it goes through the pyramids, it crosses to the other side of the body and consists of two neurons, the UMN in the CNS and then the neuron going to the effector in the PNS, the LMN. This pathway is known as the corticospinal pathway. If it does not go through the pyramids, it is an ipsilateral polysynaptic pathway involved more with posture, rather than voluntary movement.

31. UMN is motor neuron in CNS and LMN is motor neuron in PNS

32. Anatomical changes, synapse changes, more synaptic pathways, more neurotransmitter.