Week 12 - How does it all work?

Question 1

Where does the spinal cord come from?

Answer 1

foramen magnum to the first or second lumbar vertebrae

Question 2

How many pairs of spinal nerves are there?

Answer 2

31

Question 3

What are the regions of the spinal cord?

Answer 3

cervical, thoracic, lumbar, sacral, coccygeal

Question 4

Where are the enlargements of the spinal cord?

Answer 4

cervical and lumbosacral regions –> arms and legs

Question 5

What is the cauda equina?

Answer 5

branches from the L5 enlargement

Question 6

What are the meninges

Answer 6

connective tissue covering the spinal cord and brains

Question 7

What are the functions of the meninges?

Answer 7

• protect CNS and blood vessels
• contains CSF
• forms partitions in the skull

Question 8

Describe the three meningeal layers in the spinal cord?

Answer 8

Dura mater
-contains subdural space –> serous fluid
Arachnoid mater
-contains subarachnoid space –> cerebrospinal fluid and blood vessels
Pia mater
-many small blood vessels

Question 9

Where are sensory and motor neurons found?

Answer 9

sensory: dorsal roots
motor: ventral roots

Question 10

What is the structure of a nerve?

Answer 10

• endoneurium - surrounds axon and associated schwann cells
• perineurium - surrounds a group of axons or a nerve fascicle
• epineurium - surrounds a group of fascicles

Question 11

How many cervical, thoracic, lumbar, sacral and coccygeal nerves are there?

Answer 11

Cervical: 8 pairs
Thoracic: 12 pairs
Lumbar: 5 pairs
Sacral: 5 pairs
Coccygeal: 1 pair

Question 12

What are the parts of the brain?

Answer 12

• forebrain –> cerebrum, diencephalon
• midbrain
• hindbrain –> pons, medulla oblongata, cerebellum

Question 13

Which parts form the branistem?

Answer 13

midbrain, hindbrain (pons, medulla oblongata)

Question 14

Medulla oblongata

Answer 14

• autonomic reflex centre
• cardiovascular centre - regulates heart rate, force of contractions, blood vessel diameter
• respiratory centre - regulates rate and depth of breathing
• other reflexes - swallowing, vomiting, hiccuping, coughing, sneezing

Question 15

Pons

Answer 15

• contains conduction tracts: longitudinal (spinal cord –> higher brain centres; transverse tracts (cerebrum and cerebellum)
• sleep centre (REM)
• respiratory centre (works with medulla oblongata)

Question 16

Midbrain

Answer 16

• receives visual, auditory and tactile sensory output
• generates reflex movements of head, eyes, body
• controls movement of the eye

Question 17

cerebellum

Answer 17

-controls locomotion, in association with cerebrum
-fine motor control
posture and balance

Question 18

What does the diencephalon consist of?

Answer 18

• thalamus
• subthalamus
• epithalamus
• hypothalamus

Question 19

What are gyri, fissures and sulci?

Answer 19

Gyri: elevated tissue or folds
Sulci: groove
Fissures: deep grooves

Question 20

What are longitudinal fissures?

Answer 20

separates left and right hemispheres

Question 21

What is the lateral fissure?

Answer 21

separates temporal lobe from the rest of the cerebrum

Question 22

Precentral gyrus?

Answer 22

primary somatic motor cortex

Question 23

Postcentral gyrus?

Answer 23

primary somatic sensory cortex (primary somatosensory cortex)

Question 24

Frontal lobe?

Answer 24

voluntary motor function, motivation, planning, aggression, sense of smell, regulation of emotional behaviour and mood

Question 25

Parietal lobe?

Answer 25

area which receives the most sensory input except for smell, hearing, taste and vision

Question 26

Occipital lobe?

Answer 26

receives and processes visual input

Question 27

Temporal lobe?

Answer 27

receives and processes smell and hearing, role in memory

Question 28

What are the lobes of the cerebrum?

Answer 28

frontal, parietal, occipital, temportal

Question 29

What is the function of the corpus callosum?

Answer 29

connects two vertebral hemispheres together

Question 30

What is the role of limbic system?

Answer 30

role in memory, development of neuropathways

Question 31

Describe the meningeal layers of the brain?

Answer 31

``` Dura mater -periosteal dura dural venous sinus: venous blood, dural folds -meningeal dura -subdural space: serous fluid Arachnoid mater -subarachnoid space: CSF and blood vessels Pia mater -many small blood vessels ```

Question 32

What are the functions of ventricles?

Answer 32

- production of CSF | - lined with ependymal cells

Question 33

Cerebrospinal fluid

Answer 33

- produced in choroid plexus - protects brain and spinal cord from trauma - provides buoyancy - similar composition to blood plasma but less proteins and different ionic concentrations

Question 34

How many cranial nerves are there?

Answer 34

12, named after Roman numerals

Question 35

Division of sympathetic division?

Answer 35

thoracolumbar

Question 36

Division of the parasympathetic division?

Answer 36

craniosacral

Question 37

Autocrine

Answer 37

local effect on the same cell type from which the chemical signals are released

Question 38

Paracrine

Answer 38

affect other cell types locally without being transported in the blood

Question 39

Neurotransmitter

Answer 39

produced by neurons, secreted into extracellular space

Question 40

Endocrine

Answer 40

produced by cells of endocrine glands, enters circulatory system and affects distance cells

Question 41

Characteristics of hormones

Answer 41

- produced in small quantities - transported some distance in the circulatory system - acts of target tissue elsewhere in the body

Question 42

Types of hormone secretion

Answer 42

- acute: sudden release duer to stimulus - chronic: small variations over long periods - episodic: estrogen and progesterone

Question 43

What are some functions of the endocrine system?

Answer 43

metabolism, control of food intake and digestion, tissue maturation, ion regulation, water balance, HR and BP regulation, control of blood glucose and other nutrients, controls reproductive functions, uterine contraction and milk release, immune system regulation

Question 44

Difference between posterior and anterior pituitary

Answer 44

- posterior: nervous tissue | anterior: endocrine tissue

Question 45

Describe the relationship between the anterior pituitary and hypothalamus

Answer 45

-releasing and inhibiting factors produced by the hypothalamus pass to anterior pituitary, causing it to release hormones

Question 46

What are the hormones of the anterior pituitary?

Answer 46

Growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, melanocyte-stimulating hormone, luitenizing hormone, prolactin

Question 47

Describe the relationship between the posterior pituitary and hypothalamus

Answer 47

-nervous stimulation of cells of posterior pituitary cause the posterior pituitary to release hormones

Question 48

What are the hormones of the posterior pituitary?

Answer 48

ADH, oxytocin

Question 49

Give an example of negative feedback

Answer 49

T3 and T4 from thyroid gland, when enough is in the blood stream, the thyroid stops producing it until it is needed again

Question 50

Give an example of positive feedback

Answer 50

oxytocin during childbirth, uterine contractions cause the release of oxytocin