Homeostasis - The Central Nervous System

Question 1

How do the meninges and cerebrospinal fluid protect + support the brain?

Answer 1

• Meninges: three layers of connective tissue surround and protect brain + spinal cord
• Cerebrospinal fluid circulates through central canal of spinal cord, ventricles of brain, + between 2 meninges. Cushions brain + spinal cord from jarring movements + impacts, nourishes, + protects from toxic substances

Question 2

Grey matter vs white matter

Answer 2

Grey matter: tissue of brain + spinal cord containing cell bodies + dendrites of neurons

White matter: tissue of brain + spinal cord containing axons of neurons

Question 3

How to afferent/efferent neurons + interneurons connect to the spinal cord?

Answer 3

• Afferent axons enter through dorsal root + make synapses w/ interneurons in grey matter
• Interneurons send axons upward through white matter of spinal cord to brain
• Efferent axons pass downward through white matter + make synapses w/ efferent neurons in grey matter. Axons from these neurons then exit spinal cord through ventral root

Question 4

Forebrain, midbrain, and hindbrain functions

Answer 4

• Forebrain: processing, thinking, understanding
• Midbrain: relaying info between hindbrain + forebrain
• Hindbrain: basic life functions + muscle control

Question 5

Medulla oblongata function

Answer 5

Connects spinal cord to cerebellum, contains nerve centres for involuntary behaviours such as breathing, heart rate, + blood pressure

Question 6

Cerebellum function

Answer 6

Voluntary muscle movements, balance, fine motor control

Question 7

Pons function

Answer 7

Connects cerebellum to higher centres in brain

Question 8

Cerebrum/cerebral cortex function

Answer 8

Higher-level processes including language, memory, reasoning, thought, learning, decision-making, emotion, intelligence and personality

Question 9

Frontal lobe, parietal lobe, occipital lobe, temporal lobe functions

Answer 9

• Frontal lobe: memory formation, emotions, decision making/reasoning, personality
• Parietal lobe: senses, spatial awareness, perception
• Occipital lobe: processing, integration, + interpretation of visual stimuli
• Temporal lobe: hearing, language comprehension, memory, memory formation

Question 10

Thalamus function

Answer 10

Interprets sensory input + signals appropriate regions in cerebral cortex. Alerts cerebral cortex to full wakefulness + inducing sleep

Question 11

Hypothalamus function

Answer 11

Regulates homeostatic functions such as maintaining body temp, monitoring osmotic balance, producing hormones/controlling release of hormones from pituitary gland

Question 12

Basal nuclei function

Answer 12

Grey matter centres that surround thalamus + moderate voluntary movements directed by motor centers in cerebrum

Question 13

What is the blood brain barrier + why is it important?

Answer 13

• Barrier formed by tight junctions between endothelial cells in capillaries of brain
• Block movement of most substances into brain via brainstem
• Protects brain from harmful substances such as toxins in blood, infection from viruses + bacteria