central nervous system

Question 1

what is grey matter?

Answer 1

• contains mainly cell bodies, dendrites and short, unmyelinated axons
  
  • found around outside of brain and center of spinal cord

Question 2

what is white matter?

Answer 2

• contains tracts of myelinated axons
  
  • forms some inner areas of brain and outside of spinal cord

Question 3

describe the spinal cord:

Answer 3

• column of nerve tissue that travels from brain down the spine
• collects messages and sends them to brain
• sends messages form brain to effectors
  primary reflex center - contains interneurons of most reflex arcs
• centre contains grey matter
  
  • cell bodies and dendrites of spinal neurons
• spinal cord is protected by vertebrate, soft tissue, meninges (a thick membrane) and cerebrospinal fluid

Question 4

describe the blood brain barrier:

Answer 4

• formed by meninges (membrane around CNS) and tight-walled capillaries
• keeps blood and nervous system separate
• oxygen and lipid - soluble materials can get through
• other toxins cannot

Question 5

describe the cerebrospinal fluid:

Answer 5

• circulates through spaces and around the CNS
• about 500 ml/day produced
• 150ml in system at one time
• transports hormons, white blood cells and nutrients across blood-brain barrier
• shock absorber (cushions brain)

Question 6

describe oxygen and the brain:

Answer 6

• brain makes up 2% of bodies weight
• uses 20% of bodies oxygen
• lack of oxygen for a few minutes can cause major brain damage

Question 7

what is the structure of the brain?

Answer 7

• mass of neutral tissue - grey matter outside and some white matter inside
• gelatin - like consistency
• surrounded by cerebrospinal fluid, menings and the skull

Question 8

hindbrain:

Answer 8

• cerebellum, medulla oblongata and pons
• mostly control of involuntary responses such as posture and coughing
• some fine motor voluntary control

Question 9

midbrain:

Answer 9

• small area in the center of the brain
• relays messages between fore and hindbrain
• key role in eye movement

Question 10

forebrain:

Answer 10

• thalamus, hypothalamus, cerebrum
• thoughts, memory, language, emotions and some involuntary responses

Question 11

cerebellum:

Answer 11

• walnut shaped structure near the base of the brain
• posture, some reflexes, involuntary movements
• fine voluntary motor skills such as writing
• receives information from “proprioceptors” - specialized sensors in muscles and joints

Question 12

medulla oblongata:

Answer 12

• at base of brainstem
• connects brain to spinal cord
• automatic involuntary responses
  
  • heart rate
  • constriction and dilation of blood vessels
  • rate and depth of breathing
  • swallowing
  • digestion and vomiting
  • coughing

Question 13

pons:

Answer 13

• Above and in front of medulla oblongata
• relay center between right and left cerebrum, the cerebrum and rest of the brain

Question 14

what does the midbrain do?

Answer 14

• above pons
• relays visual and auditory information between hindbrain and forebrain
• role in eye movement and skeletal muscle control

Question 15

cerebrum:

Answer 15

• largest part (4/5 of the brain)
• two hemispheres (right and left)
• responsible for thoughts, memories, understanding, consciousness and language
• convoluted to increase surface area
• further divided into lobes

Question 16

thalamus:

Answer 16

• base of forebrain
• connections between hind and forebrain
• connections between senses (except smell) and cerebellum

Question 17

hypothalamus:

Answer 17

• just below thalamus
• major link between nervous and endocrine systems
• controls (mainly through hormone production):
  
  • blood pressure
  • heart rate
  • body temperature
  • thirst and hunger
  • emotions

Question 18

corpus callosum:

Answer 18

• a bundle of white matter linking L and R hemisphere - sends signals back and forth between halves

Question 19

describe right vs left brain:

Answer 19

• both halves of brain involved in cognitive processes
• each side of brain is thought to have more of a role in certain functions

Question 20

describe the left brain:

Answer 20

• sequential and logical thinking
• linguistic skills
• mathematical ability

Question 21

describe the right brain:

Answer 21

• intuition
• visual: spatial skills
• artistic abilities

Question 22

what are the four cerebral cortex lobes?

Answer 22

• frontal
• parietal
• temporal
• occipital

Question 23

describe the frontal lobe:

Answer 23

• thought
• intelligence
• memory
• personality
• voluntary motor

Question 24

describe the parietal lobe:

Answer 24

• process sensory information from skin
• process information about body position

Question 25

describe the temporal lobe:

Answer 25

• auditory reception
• understanding speech
• retrieving visual and auditory memories
• process some visual information

Question 26

describe the occipital lobe:

Answer 26

• receive and and process visual information