CNS - The Brain, Blood Supply and Protection

Question 1

Name and describe the three protective structures of the brain and spinal cord

Answer 1

• The meninges. The dura outermost layer, which is thick, strong and protective.
• Arachnoid layer. The middle layer, which consists of fibres in connective tissue
• Pia layer. The innermost layer, thin and transparent and adheres to the surface of the brain and spinal cord

Question 2

What are the structures involved in the Cerebral circulation?

Answer 2

• Internal carotid arteries (supply anterior brain) and the vertebral arteries (supply brain stem and posterior brain)

Question 3

Describe the three functions of Cerebrolspinal fluid (CSF)

Answer 3

Mechanical protection - Protects the brain and spinal cord from trauma. Cushions brain and spinal cord
Circulation - Supplies nutrients to the nervous system and removes waste
Homeostasis function - circulates hormones

Question 4

State the four areas of the brain

Answer 4

Brainstem, Cerebellum, Diencephalon, Cerebrum

Question 5

What does the brainstem consist of?

Answer 5

Midbrain, pons, medulla oblongata

Question 6

State the function of the cerebellum

Answer 6

Smooths and coordinates contractions of skeletal muscles, regulate posture and balance and coordination of skilled movement

Question 7

What is involved in the Diencephalon

Answer 7

Epithalamus, thalamus, hypothalamus and limbic system

Question 8

State the function of the Cerebrum

Answer 8

Communicates with motor areas of the cerebral cortex and detects movement in the cerebral motor cortex

Question 9

Describe the role of the brainstem in controlling consciousness

Answer 9

The midbrain has a net-like arrangement of sensory axons carrying input to the brain to maintain consciousness

Question 10

What key system helps maintain consciousness

Answer 10

Reticular activating system (RAS)

• Turning off RAS induces sleep
• Melatonin turns off RAS
• Damage to the RAS results in a coma

Question 11

List the structures of the Diencephalon

Answer 11

Thalamus, hypothalamus and epithalamus

Question 12

Describe the function of the thalamus

Answer 12

Major relay station for sensory and motor impulses travelling to the cerebral cortex from the brainstem and spinal cord

Question 13

Describe the function of the hypothalamus

Answer 13

Regulates homeostasis, controls autonomic NS, regulates body temp, produces hormones and controls the pituitary gland

Question 14

Describe the function of the epithalamus

Answer 14

Contains the pineal gland which is an endocrine gland that produces melatonin which induces sleep

Question 15

Describe the function of the limbic system

Answer 15

Controls emotional responses, memory and processing

Question 16

Clinical implications relating to the limbic system?

Answer 16

Damage to this system will result in changes to the expression of emotion and memory impairment