Action Potential
In this step of AP, the Na+ inactivation gate is closed.
Repolarization pt 1.
What type of channel receives the Neurotransmitter across the synaptic cleft?
Binds to Ligand Receptors on the Ligand Channels
What is the function of spongy bone?
Strength, and space for the red bone marrow which produces blood cells!
What bones are created from intramembranous ossification?
Flat bones of skull, Some Facial Bones, Mandible, Central Portion of clavicle.
What is the fuction of a Canal (Meatus), Fissure, or Foramen?
How does the membrane potential return to resting after hyperpolarisation?
Due to leak channels throughout the membrane.
Where are the calcium channels located? When are they opened?
Presynaptic Neuron, These are Voltage Gated and open when they receive the AP from down the axon.
What is the function of the periosteum?
To line the external bone surface and contain surrounding blood vessels and nerves.
How can a physician tell if you are done growing?
The closing of an epiphyseal plate and the presence of an ossified epiphyseal plate.
What and where are your 4 types of sinuses?
Frontal (Forehead)
Sphenoid (In head)
Ethmoid (Behind eyes)
Maxillary (in cheeks)
What is the difference between Relative and Absolute Refractory Period?
Relative: Extra Strong Stimulus can cause an AP
Absolute: No new AP can occur.
What are two types of Summation? How do they differ?
Temporal- Repeated release of Neurotransmitter at ONE Synapse.
Spatial- Release of neurotransmitter at several synapses at once.
What does cartilage do for bones?
1. Helps with Articulations, (Protects + Resists compression)
2. Precursor for bone growth
What are steps to Endochondral Ossification?
1. Fetal Hyaline Cartilage
2. Osteoblasts (Which Build Bone Collar "Early compact bone")
3. Spongy Bone forms and medullary cavity develops.
4. Epiphyseal plate develops, bone replaces cartilage, epiphyses finishes ossifying.
A patient with a deviated septum might show these symptoms:
1. Increased sinus Infections
2. Sleep Apnea & Snoring
3.Repeated Sneezing
4. Nose Bleeds
5. Mild to Severe loss of smell.
How does propagation of an AP Occur?
AP propagates through section of axolemma, Depolarization triggers adjacent voltage gated Na+, and the previous section repolarizes and enters refractory.
What are the 3 kinds of Termination? Explain each.
Degradation: NT Destroyed by enzyme
Reuptake: NT pumped back into Presynaptic Neuron
Diffusion: NT Diffuses away
What is the function of the Epiphyses?
1. Strengthens joints
2. Attatchment side for tendons/ligaments
What are steps to Intramembranous Ossification?
1. Starts from Mesenchyme
2. Turns into osteoblasts which starts calcification,
3. Periosteum and spongy bone forms,
4. Early Compact bone formation.
What would a Bilateral cleft lip with a complete palate look like?
2 sides, entire palate to Nostril,
Which is faster Saltatory or Continuous Conduction, Explain Why?
Saltatory, Because in this form of conduction only the myelin sheath gaps must generate the AP. (It easily passes through the Myelin!)
What are the steps in order of the events happening at the Synapse?
1. AP triggers Ca2+ channels to open
2. Influx of Ca2+ causes synaptic vessicles to release NT into synaptic cleft.
3. NT diffuses across the cleft and binds to receptors on Postsynaptic neuron.
4. Ion channels open on PSN, leading to local potential!
What are 6 functions of skeletal system?
1.Protection
2. Mineral Storage and acid-base homeostasis
3. Blood cell formation
4. Fat Storage
5. Movement
6. Support
What are the two types of bone growth, and how do they differ?
Appositional growth: in diameter, Osteoblast in periosteum, and osteoclasts in medullary cavity.
Interstitial: in length; at epiphyseal plate.
Name 4 Projections and 4 Depressions
Projections: Condyle, Crest, Tubercle, Epicondyle, Process.
Depressions: Fossa, Facet, Fovea, Groove