Lecture 13 Flashcards
What is the function of a nervous system?
- coordinate the activity of the muscles
- monitor (regulate) the organs
- construct and stop (control) input from the senses (sight, hearing, touch, smell, taste)
- initiate actions
What are cells that receive sensations called?
Receptors
What are cells that make the appropriate response called?
Effectors
What are the two sub-divisions of the Nervous System?
- Central Nervous System(CNS):
- Brain
- Spinal cord - Peripheral Nervous System(PNS):
- All other nerves and neurons that do not lie within the CNS
How does the CNS develop?
Under the control of the notocord, the ectodermal cells come together to form a plate, crest, then finally a tube. This tube is the CNS
What is the development of the CNS called?
Neurulation
What are malformations of the neural tube called?
Neural Tube Disorders (NTDs)
What are the most common tube defects?
- Anencephaly (head):
When the anterior part of the tube fails to close over. The brain doesn’t form properly. - Encephalocele (head)
When the tube doesn’t close properly and some of the fluid forms a bag-like structure coming off of the head. - Spina bifida (spine):
When the posterior part of the tube doesn’t close completely. Results in some of the musculature that would normally be around the base of the spine to be able to protrude out/grow uncontrolled
How to prevent Neural Tube Disorders (NTDs)?
Take folic acid supplements early on and before pregnancy (vitamin b)
Why take vitamin b to combat NTDs?
Bc the DNA synthesises thats happening at the very early stages of embryo development requires folic acid to occur successfully
What are the two parts of the PNS?
- Autonomic nervous system (ANS)
- Somatic nervous system
Somatic nervous system function?
- Controls all of the conscious movement in the body (through efferent nerves)
- Deals with sensory information being sent into the CNS (through afferent nerve)
Autonomic nervous system (ANS) catagories?
- Sympathetic
- Parasympathetic
- Enteric
Autonomic nervous system (ANS) function?
- Controls all of the unconscious movement in the body
- Supplies all the internal organs
Sympathetic?
- Excites muscle (fight or flight responses)