Randos 🫣
Is a positive feedback loop considered homeostatic? Why or why not
No, because negative feedback counteracts a change in the body and returns the system to its original target value (set point). Positive feedback pushes the body away from its set point.
Describe the pathway from sensor to motor action (5 steps/components)
sensor, afferent nerves, integrator, efferent nerves, effector
Match each receptor to its function:
Alpha1, Alpha2, Beta1, Beta2, Beta3
1. bronchodilation and responds only to epinephrine
2. vasoconstriction and sphincter contraction
3. lipolysis in adipose tissue
4. increases heart rate and contractility
5. inhibitory and helps coordinate sympathetic and parasympathetic activity
1. Beta2
2. Alpha1
3. Beta3
4. Beta1
5. Alpha2
The SNS activates the ___ response, and is also considered the ___ division
fight or flight; thoracolumbar
The PNS activates the ___ response, and is also considered the ___ division
rest and digest; craniosacral
What 3 structures only get sympathetic innervation
blood vessels, sweat glands, heart ventricles
blood clotting -> ___ feedback
body temperature regulation -> ___ feedback
child labour -> ___ feedback
blood glucose regulation -> ___ feedback
calcium regulation -> ___ feedback
positive, negative, positive, negative, negative
Compare nicotinic and muscarinic receptors based on:
What are the cells that release epinephrine and norepinephrine from the adrenal medulla, and at what percentage of each
Chromaffin cells; 80% epi, 20% norepi
What are the two enzymes that break down ACh and where does each act
acetylcholinesterase at the synapse
pseudocholinesterase in surrounding tissues
What are the 9 regions of the abdomen, and point to your body to show their locations
Right hypochondriac region
Epigastric region
Left hypochondriac region
Right lumbar region
Umbilical region
Left lumbar region
Right iliac region
Hypogastric region
Left iliac region
Match each characteristic of epithelial tissue to its definition:
avascular, cellularity, polarity, attachment
1. The free edge (apical surface) is in contact with exterior of body or luminal space, while the basal surface anchors the cell to basement membrane
2. Epithelial tissue is supported by underlying basement membrane
3. Rely on connective tissue for vascular supply
4. Unusually predominantly cellular and is tightly packed
1. polarity
2. attachment
3. avascular
4. cellularity
What are the 4 toxins of the neuromuscular junction and their mechanisms
curare: competitive antagonist of ACh -> stop muscle contraction
botulinum: blocks release of ACh -> stop muscle contraction
black widow spider venom: big release of ACh from the presynaptic neuron -> muscle spasm -> stop muscle contraction
organophosphates (insecticides/nerve gases): binds to and irreversibly inhibits acetylcholinesterase -> prevent breakdown of ACh -> muscle spasm -> stop mucle contraction
In the sympathetic nervous system, ______ receptors are most responsive to norepinephrine, while ______ receptors are most responsive to epinephrine
α1 receptors, β2 receptors
What are the nerves that carry parasympathetic signals (full names and number) (hint: not just the cranial nerves)
Oculomotor (CN III), Facial (CN VII), Glossopharyngeal (CN IX), Vagus (CN X), and sacral nerves from S2-S4
Is this an upper or lower motor neuron lesion:
A patient presents with muscle weakness. On examination:
upper motor neuron lesion
Provide an example of tissue that you would find each epithelial cell type:
Stratified cuboidal epithelium
Simple columnar epithelium
Simple squamous epithelium
Stratified squamous epithelium
1. Excretory ducts (sweat/mammary/salivary glands) and male urethra
2. GI tract
3. Alveoli or blood vessels
4. Epidermis of the skin (keratinized) or esophagus (non-keratinized)
The somatic nervous system exits the ___ region of spinal cord grey matter
The SNS of the autonomic nervous system exits the ___ region of spinal cord grey matter
Anterior (Ventral) Horns
Lateral Grey Horns
Fill in the blanks for the SNS:
Preganglionic fiber length______
Postganglionic fiber length______
Ganglia location______
Postganglionic neurotransmitter (typical)______
Fill in the blanks for the SNS:
Preganglionic fiber length: short
Postganglionic fiber length: long
Ganglia location: near spinal cord
Postganglionic neurotransmitter (typical): NE
Fill in the blanks for the PNS:
Preganglionic fiber length___
Postganglionic fiber length___
Ganglia location___
Postganglionic neurotransmitter (typical)___
Fill in the blanks for the PNS:
Preganglionic fiber length: long
Postganglionic fiber length: short
Ganglia location: close to or within target organs
Postganglionic neurotransmitter (typical): ACh
Draw a map of the body cavities and what they each contain... yes, the whole thing
Dorsal -> vertebral (spinal cord) + cranial (brain)
Ventral -> thoracic + abdominopelvic *separated by diaphragm*
Abdominopelvic -> abdominal + pelvic
Thoracic -> 2 pleural (lungs) + mediastinal
Mediastinal -> pericardial (heart) + superior mediastinum (trachea, esophagus, major vessels)
Describe the mechanism and clinical symptoms of nicotinic vs. muscarinic poisoning
Nicotinic:
binds to nicotinic receptors
vomiting, diarrhea, high blood pressure, tachycardia, sweating, profuse salivation, convulsions
Muscarinic:
binds to muscarinic receptors
salivation, nausea, vomiting, diarrhea, constriction of respiratory passages, low blood pressure, bradycardia, sweating
Skeletal muscles are controlled by integrated descending motor pathways:
pyramidal tract controls the (conscious/subconscious), and is carried out by the ___ and ___ tracts
extrapyramidal tract controls the (conscious/subconscious), and is carried out by the ___ and ___ pathways
conscious; corticobulbar and corticospinal tracts
subconscious; medial and lateral pathways
What are the 3 groups of sympathetic ganglia, and describe the following of each group:
- Location
- Type of ganglia
- Controls what effectors
Sympathetic chain (paravertebral) ganglia:
- both sides of vertebral column
- 3 cervical (superior, middle, and inferior) - 10–12 thoracic - 4–5 lumbar - 4–5 sacral & 1 coccygeal ganglia
- head, limbs, thoracic cavity, and body wall
Collateral (prevertebral) ganglia
- anterior to vertebral bodies
- coeliac, superior mesenteric & inferior mesenteric ganglia
- abdominopelvic cavity
Adrenal medulla:
- center of each adrenal gland
- preganglionic fibers synapse on chromaffin cells and THEREFORE have no postganglionic fibers
- release neurotransmitters into bloodstream
Which cranial nerve provides 75% of all parasympathetic outflow
vagus nerve (CN X)