Bio Lecture Mock Exam Flashcards

Mock Exam for Bio Lecture

Neuron Physiology

• Absolute Refractory Period:
  • During this period, a neuron cannot initiate another action potential, regardless of the stimulus strength. The Sodium (Na+) channels are inactive at this time.
  • Thus, the answer to question 1 is C.

Brain Anatomy

• Arbor Vitae:
  • The arbor vitae is a part of the cerebellum.
  • It's the distinctive branching pattern of white matter observed in the cerebellum when it is cut in a midsagittal section.
  • Thus, the answer to question 2 is C.

Cranial Nerves

• Bell's Palsy:

  • Bell's palsy is caused by dysfunction of the CN VII (Facial) nerve.
  • Thus, the appropriate answer for question 3 is B.

• Cranial Nerve Functions:

  • CN I (Olfactory): Responsible for the sense of smell (Question 9, answer B).
  • CN IX: Also known as the Glossopharyngeal nerve (Question 10, answer A).
  • CN VI: Controls lateral eye movement (Question 11, answer C).
  • CN VII: Primarily involved in facial expressions (Question 12, answer B).
  • CN VIII: Involved in balance and hearing (Question 13, answer B).
  • CN X: Also known as the Vagus nerve (Question 14, answer C).
  • CN XII (Hypoglossal): Controls swallowing and tongue movements (Question 26, answer C).

Neuroglia

• Blood-Brain Barrier:
  • The blood-brain barrier is mainly maintained by astrocytes.
  • These glial cells surround blood vessels in the brain and regulate the passage of substances into the brain tissue.
  • Thus, the answer to question 4 is C.
• Ependymal cells
  • Produce cerebrospinal fluid (CSF) (Question 20, answer B)
• Microglia
  • Act as Immune defense cells of the CNS (Question 29, answer C).
• Oligodendrocytes
  • Produce myelin in the CNS (Question 31, answer B).
• Schwann cells
  • Produce myelin in the PNS (Question 37, answer B).

Peripheral Nervous System

• Brachial Plexus:
  • The brachial plexus supplies nerves to the upper limbs.
  • Thus, the answer to question 5 is B.

Brain Organization

• Brainstem:

  • The brainstem includes the pons, medulla oblongata, and midbrain.
  • The thalamus is NOT part of the brainstem; it's part of the diencephalon.
  • Thus, the answer to question 6 is D.

• Broca's Area:

  • Broca's area is critical for speaking.
  • It is located in the frontal lobe and is associated with speech production.
  • Thus, the answer to question 7 is B.

• Falx Cerebri:

  • The falx cerebri separates the two cerebral hemispheres.
  • Thus, the answer to question 21 is B.

• Primary Motor Cortex:

  • The primary motor cortex is located in the frontal lobe.
  • Thus, the answer to question 34 is C.

Autonomic Nervous System

• Sympathetic Nervous System:
  • Cell bodies of preganglionic neurons of the sympathetic nervous system are found in the lateral horn of the spinal cord.
  • Thus, the answer to question 8 is C.

Spinal Cord

• Spinal Cord Organization:
  • Columns in the spinal cord are bundles of nerve fibers (white matter).
  • Thus, the answer to question 15 is B.
• Commissures
  • connect the left and right sides of the CNS (Question 16, answer A).
• Filum Terminale:
  • The filum terminale anchors the spinal cord to the coccyx.
  • Thus, the answer to question 22 is A.
• Dorsal Ramus:
  • The dorsal ramus carries mixed fibers to/from the back.
  • Thus, the answer to question 19 is C.

Action Potentials

• Continuous Propagation:

  • Continuous propagation occurs in unmyelinated axons.
  • This is a slower form of propagation compared to saltatory conduction in myelinated axons.
  • Thus, the answer to question 17 is B.

• Depolarization:

  • Depolarization means making the inside of the cell less negative.
  • It involves an influx of positive ions (e.g., Na+) into the cell.
  • Thus, the answer to question 18 is B.

• Spatial Summation:

  • Spatial summation refers to several neurons firing at once on one target.
  • This increases the likelihood of the target neuron reaching its threshold for firing an action potential.
  • Thus, the answer to question 38 is A.

• Voltage-Gated Channels

  • Open in response to Electrical changes (voltage) (Question 44, answer C).

Cerebrospinal Fluid (CSF)

• CSF Flow:
  • The correct flow of CSF is: Lateral ventricles → Third ventricle → Fourth ventricle → Subarachnoid space.
  • Thus, the answer to question 23 is B.
• Subarachnoid space
  • Contains CSF (Question 42, answer C).

Thalamus

• Thalamus Function:
  • The primary function of the thalamus is to relay sensory and motor signals.
  • Thus, the answer to question 24 is C.

Sensory Receptors

• Golgi Tendon Organs:
  • Golgi tendon organs are tension detectors in tendons.
  • Thus, the answer to question 25 is C.
• Proprioceptors
  • Detect body position (Question 35, answer C).

Hypothalamus

• Hypothalamus Functions:
  • The hypothalamus regulates thirst, controls body temperature, and controls hunger.
  • It does NOT produce CSF.
  • Thus, the answer to question 27 is C.

Medulla Oblongata

• Medulla Oblongata Function:
  • The medulla oblongata is responsible for heart rate and breathing regulation.
  • Thus, the answer to question 28 is B.

Neurological Disorders

• Substantia Nigra:
  • Loss of neurons in the substantia nigra leads to Parkinson's disease.
  • Thus, the answer to question 32 is B.

Nerves and Muscles

• Phrenic Nerve:
  • The phrenic nerve controls the diaphragm (breathing).
  • Thus, the answer to question 33 is B.

Reflexes

• Reflexes:
  • Reflexes are fast, automatic responses to stimuli.
  • Thus, the answer to question 36 is B.
• Spinal Reflex Arc
  • Includes A) Sensory receptor B) Sensory neuron C) Motor neuron
  • Does NOT include D) Cerebral cortex (Question 41, answer D).

Special Senses

• Special Senses:
  • Special senses include taste, smell, and balance.
  • Touch is NOT considered a special sense; it is a general sense.
  • Thus, the answer to question 39 is D.

Spinal Nerves

• Plexuses:
  • Thoracic spinal nerves do NOT form plexuses, unlike cervical, lumbar, and sacral spinal nerves.
  • Thus, the answer to question 40 is A.

Autonomic Nervous System

• Sympathetic Nervous System Functions:
  • The sympathetic nervous system functions to promote fight or flight responses.
  • Thus, the answer to question 43 is C.

Olfactory Cortex

• Olfactory cortex process
  • Smell (Question 30, answer B).