Anatomy II Review Flashcards
What is the function of dendrites in a neuron?
Dendrites are the receiving end of a neuron that receives signals from other neurons.
What is the main function of an axon?
Axon transmits electrical impulses away from the neuron’s cell body.
What are the three protective layers surrounding nerve fibers?
Epineurium, Perineurium, and Endoneurium.
What are ascending tracts in white matter responsible for?
Ascending tracts are responsible for sensory pathways.
What are descending tracts in white matter responsible for?
Descending tracts are responsible for motor pathways.
Where are the cell bodies for lower motor neurons located?
In the ventral horn of the spinal cord.
What is the function of the dorsal root in the grey matter?
The dorsal root is responsible for sensory processing.
Where are the cell bodies of the dorsal root located?
In the dorsal root ganglia outside the spinal cord.
In which regions is the lateral horn found?
The lateral horn is found only in the thoracic and lumbar regions.
What is a reflex arc?
A reflex arc bypasses the CNS and directly sends signals from a sensory neuron to a motor neuron.
Why are skeletal motor neuron pathways faster than visceral motor neuron pathways?
Skeletal motor neurons have a one-neuron pathway, while visceral motor neurons have a two-neuron pathway.
What constitutes the Central Nervous System (CNS)?
The brain and spinal cord.
What constitutes the Peripheral Nervous System (PNS)?
Cranial and spinal nerves.
What does the somatic nervous system control?
The somatic nervous system controls voluntary skeletal muscles.
Where are the cell bodies of motor neurons in the somatic nervous system located?
In the CNS (brain or ventral cord of the spinal cord).
What does the autonomic nervous system regulate?
It regulates involuntary bodily functions such as heart rate, digestion, and respiratory rate.
What are the two branches of the autonomic nervous system?
Sympathetic and parasympathetic branches.
What is Horner’s syndrome?
Horner’s syndrome is caused by disruption of the sympathetic nerve pathway to the face and eye.
What is Raynaud’s syndrome?
Raynaud’s syndrome involves excessive constriction of small arteries in response to cold.
What does the epimysium cover?
The epimysium covers the whole muscle.
What does the perimysium cover?
The perimysium covers bundles of muscle fibers (fasciculi).
What does the endomysium cover?
The endomysium covers individual muscle fibers.
What initiates the sliding filament theory?
An electrical impulse at the neuromuscular junction.
What happens when Ca++ binds to troponin?
Tropomyosin uncovers active sites on actin.
What is formed when myosin heads bind to actin?
Actomyosin complex.
What is a motor unit?
A motor neuron and the muscle fibers it innervates.
What are the two divisions of motor neurons?
Upper and lower motor neurons.
What are the three branches of the aortic arch?
Brachiocephalic Trunk, Left Subclavian, Left Common Carotid.
What are the three layers of the heart?
Pericardial sac, myocardium, endocardium.
How do arteries and veins differ in structure?
Arteries have thicker walls, veins have thinner walls and rely on valves.
What is the function of intercalated discs?
They transmit electrical signals in cardiac muscle to maintain heart rhythm.
What do Purkinje fibers do?
They help spread the electrical signal rapidly through the ventricles.
What do AV valves prevent?
Backflow of blood into the atria during ventricular systole.
When do semilunar valves open?
Under the pressure of ventricular contraction.
What is cardiac output (CO)?
CO = SV x HR.
What does the P wave in an EKG represent?
Atrial depolarization.
What is the normal ejection fraction (EF)?
Around 60%.
What are the coronary arteries that supply the heart?
Right and left coronary arteries.
What are alveolar sacs?
The site of gas exchange in the lungs.
What is the function of surfactant in the lungs?
Surfactant reduces surface tension, preventing alveolar collapse.
What happens when the diaphragm contracts?
It pushes down, increasing thoracic cavity volume and allowing air into the lungs.
What is anatomical dead space?
Air that enters the body but is not available for gas exchange.
What is tidal volume (TV)?
600 mL.
What is inspiratory reserve volume (IRV)?
3000 mL.
What is functional residual capacity (FRC)?
2400 mL.
What is total lung capacity (TLC)?
6000 mL.
What do lacteals absorb?
Dietary fats.
What does lymph reabsorb?
Interstitial fluid without proteins or red blood cells.
Where does the left thoracic duct drain?
Into the left internal jugular and left subclavian.
What hormones does the anterior pituitary release?
GH, FSH, LH, MSH, TSH.
What hormones does the posterior pituitary store and release?
ADH, Oxytocin.
What hormone is released in response to consuming sugar?
Insulin.
What is the function of insulin?
Insulin stores glucose.
What is the function of glucagon?
Glucagon releases stored glucose.
What is the function of thyroid hormone?
Increases metabolism.
What is the function of calcitonin?
Stores calcium when blood levels are high.
What is the function of parathyroid hormone?
Increases blood calcium by breaking down bone.
What does the adrenal medulla release?
Norepinephrine.
What does the adrenal cortex release?
Aldosterone and glucocorticoids like cortisol.
What is the functional unit of the kidney?
Nephron.
What is the role of Bowman’s capsule?
Receives filtrate.
What is the role of the proximal convoluted tubule?
Reabsorption of water and solutes.
What is the role of the Loop of Henle?
Regulates urine concentration.
What is the role of the distal convoluted tubule and collecting duct?
Reabsorption of water and electrolytes.
How much filtrate is produced daily?
Approximately 180 L/day.
What is glucosuria?
Sugar in the urine.
What does peristalsis refer to?
Rhythmic contractions of smooth muscle.
Where does bile from the gallbladder go?
Into the duodenum.
What is the function of the jejunum?
Main site of absorption in the small intestine.
What are the divisions of the colon?
Cecum, ascending, transverse, descending, rectum, anus.
What type of tissue is in the papillary layer?
Loose areolar connective tissue.
What type of tissue is in the reticular layer?
Dense irregular connective tissue.
What is a first-degree burn?
Burn affecting only the epidermis.
What is a second-degree burn?
Burn affecting the epidermis and dermis, causing blistering.
What is a third-degree burn?
Full-thickness burn destroying the epidermis, dermis, and part of the hypodermis.
What do semicircular canals detect?
Movement in different planes (rotational, sagittal, frontal).
What is the vestibulo-ocular reflex?
It helps maintain stable vision during head movements.
