ANAPHY LAB Review: Exercises 16 - 26

Comprehensive 300-flashcard question-and-answer study deck for Anatomy & Physiology laboratory exercises covering the nervous system, spinal cord, somatic nerves, brain, cranial nerves, reflexes, sensory receptors, taste, smell, eye, vision, ear, hearing, balance, endocrine system, and blood testing.

Based on the provided anatomical drawings, what two structural neuron types are depicted?

The top neuron represents a multipolar neuron, and the bottom neuron represents a pseudo-unipolar neuron.

In the diagram of the multipolar neuron, what structure is designated by label 'a'?

Dendrite

In the diagram of the multipolar neuron, what central region is indicated by label 'b'?

Neuron cell body (soma)

In the diagram of the multipolar neuron, what specialized structure within the cell body is indicated by label 'c'?

Nissl body

In the diagram of the multipolar neuron, what conducting process is indicated by label 'd'?

Axon

In the diagram of the pseudo-unipolar neuron, what structure is designated by label 'a'?

Neuron cell body

In the diagram of the pseudo-unipolar neuron, what internal organelle is designated by label 'b'?

Nucleus

In the diagram of the pseudo-unipolar neuron, what elongated nerve process is designated by label 'c'?

Axon

What are the three primary functions of an astrocyte in the central nervous system?

An astrocyte forms the blood-brain barrier, provides structural support, and regulates the chemical environment around neurons.

What anatomical structures do ependymal cells line?

They line the fluid-filled ventricles of the brain and the central canal of the spinal cord.

What are the primary functions of ependymal cells regarding cerebrospinal fluid?

They actively produce, secrete, and circulate cerebrospinal fluid (CSF) using their cilia.

What cellular structures on ependymal cells help circulate cerebrospinal fluid?

Cilia

What is the function of an oligodendrocyte in the central nervous system?

It extends multiple processes to wrap around nerve fibers, forming the insulating myelin sheath that speeds up electrical signal transmission in the CNS.

To which division of the nervous system does the brain belong, and what role does it serve?

It belongs to the CNS (Central Nervous System), serving as the main control center.

A spinal nerve belongs to which division of the nervous system?

The PNS (Peripheral Nervous System).

To which major division of the nervous system does the spinal cord belong?

The CNS (Central Nervous System).

Which division of the nervous system is dedicated to subconscious function?

The ANS (Autonomic Nervous System).

What does the abbreviation CNS stand for?

Central Nervous System

What are the three main parts of a neuron and their basic roles?

(1) Dendrites (receive signals), (2) cell body (processes information), and (3) axon (transmits signals away).

In which part of the neuron is the nucleus found?

Within the cell body (soma).

What is another functional name for an efferent neuron?

Motor neuron

What structural classification describes a neuron with a soma, a dendrite on one side, and an axon on the other?

Bipolar neuron (it has exactly two extensions: one axon and one dendrite).

What is the narrow space across which two adjacent neurons communicate called?

The synaptic cleft

In terms of function, how are glial cells different from neurons?

Glial cells provide structural support, protection, insulation, and nourishment, rather than generating and conducting electrical nerve impulses.

In which nervous system division are neurolemmocytes (Schwann cells) located?

The PNS (Peripheral Nervous System).

What kind of biochemical material constitutes myelin?

Lipoprotein material

What are the percentage proportions of lipids and proteins in myelin?

$80\%$ lipid and $20\%$ protein.

What structural classification of neuron has multiple dendrites and a single axon extending from the soma?

Multipolar neuron

What structural classification of neuron has a single short process emerging from the cell body that branches into central and peripheral processes?

Pseudo-unipolar neuron

What organelle component inside the neuron soma corresponds to rough endoplasmic reticulum and free ribosomes?

Nissl bodies

In the spinal cord, what type of nerve transmission travels through the ventral horn?

Motor transmission

In the spinal cord, what type of nerve transmission travels through the dorsal horn?

Sensory transmission

What type of transmission travels through ascending spinal tracts?

Sensory transmission

What type of transmission travels through descending spinal tracts?

Motor transmission

What physiological factor causes the cervical enlargement of the spinal cord?

A large concentration of motor and sensory neurons required to control and receive input from the upper limbs.

Where is the filum terminale located, and what is its function?

It extends from the conus medullaris to the coccyx, anchoring the spinal cord.

What is the conus medullaris?

The tapered, cone-shaped terminal end of the spinal cord.

What is the cauda equina, and what descriptive structure does it resemble?

A group of spinal nerve roots below the spinal cord that looks like a horse's tail.

In the spinal cord cross-section, which tissue layer is deep: white matter or gray matter?

Gray matter is deep to the white matter.

What is the bridge of gray matter located between the lateral halves of the spinal cord called?

Gray commissure

The subarachnoid space surrounding the spinal cord is filled with what fluid?

Cerebrospinal fluid (CSF)

Which major peripheral nerve arises from the cervical plexus?

Phrenic nerve

Which five major nerves arise from the brachial plexus?

Axillary, musculocutaneous, radial, median, and ulnar nerves.

Which major nerves arise from the lumbar plexus?

Femoral nerve and obturator nerve.

Which major nerve arises from the sacral plexus?

Sciatic nerve

In terms of function, how does the dorsal spinal root differ from the ventral spinal root?

The dorsal root carries sensory information towards the spinal cord, while the ventral root carries motor signals away from it.

What is the endoneurium?

The connective tissue sheath that wraps around a single nerve fiber.

How do tracts differ from nerves in terms of anatomical location?

Tracts are bundles of nerve fibers found in the brain and spinal cord (CNS), while nerves are bundles of nerve fibers found outside the brain and spinal cord (PNS).

What is a mixed nerve?

A nerve that carries both sensory and motor fibers.

Which nerve regulates the contractions of the diaphragm?

Phrenic nerve

Which nerve innervates arm muscles such as the biceps brachii?

Musculocutaneous nerve

The extensor muscles of the hand are controlled by which nerve?

Radial nerve

The sciatic nerve is composed of which two nerves bound together?

Medial tibial nerve and lateral common fibular nerve.

If a person has sensation from the deltoid and biceps brachii but none from the wrist extensors, where on the spinal cord has an injury likely occurred?

Likely in the lower cervical region ($C_7 - C_8$ segments), affecting the spinal nerves that supply the wrist extensors while leaving those to the deltoid and biceps intact.

In the spinal cord cross-section diagram, what is the shallow groove along the posterior midline?

Posterior median sulcus

In the spinal cord cross-section diagram, what central lumen runs through the gray commissure?

Central canal

In the spinal cord cross-section diagram, what are the posterior projections of gray matter called?

Dorsal horn

In the spinal cord cross-section diagram, what are the anterior projections of gray matter called?

Ventral horn

In the spinal cord cross-section diagram, what is the deep groove along the anterior midline?

Anterior median fissure

Which major nerve of the upper limb travels down the medial side of the forearm into the hand?

Ulnar nerve

Which major nerve of the upper limb runs down the middle of the anterior forearm to innervate the hand?

Median nerve

Which major nerve of the brachial plexus wraps around the surgical neck of the humerus to innervate the deltoid?

Axillary nerve

Which spinal plexus innervates the shoulder girdle and upper limb?

Brachial plexus

Which meningeal layer is found immediately superficial to the spinal cord and brain surface?

Pia mater

What fluid circulates through the central canal of the spinal cord?

Cerebrospinal fluid (CSF)

Which of the cranial meninges lies directly on the cerebral cortex?

Pia mater

What fluid is found within the ventricles of the brain?

Cerebrospinal fluid (CSF)

Into what cavity does cerebrospinal fluid flow directly from the cerebral aqueduct?

Fourth ventricle

What is the structural difference between a gyrus and a sulcus?

A gyrus is an elevated ridge of the cerebral cortex, while a sulcus is a shallow groove between gyri.

What are all five lobes of the cerebrum?

Frontal lobe, parietal lobe, temporal lobe, occipital lobe, and insula.

What is the primary function of the precentral gyrus?

It controls voluntary motor movement.

What primary sensory modality does the temporal lobe alone interpret?

Hearing (auditory information).

What physical depression separates the temporal lobe from the parietal lobe?

Lateral sulcus (Sylvian fissure)

What large commissural structure connects the left and right cerebral hemispheres?

Corpus callosum

What are the two major anatomical regions that compose the midbrain?

Corpora quadrigemina and cerebral peduncles.

What are the three main functions of the cerebellum?

It coordinates voluntary muscle movements, maintains posture, and regulates balance and equilibrium.

Hitting the forehead against a wall would most likely damage what cognitive and behavioral functions associated with the frontal lobe?

Higher-level reasoning, decision-making, planning, and personality, as well as voluntary motor control or expressive speech.

If a stroke affects sensations exclusively in the face and hands, why would a very large portion of the postcentral gyrus be damaged?

The face and hands occupy a disproportionately large area of the sensory homunculus due to their exceptionally high density of sensory receptors.

What functional impairments typically result from the loss of the left cerebral hemisphere?

Severe impairment of speech production and language comprehension, as major language centers are located in the left hemisphere.

What functional deficits typically result from the loss of the right cerebral hemisphere?

Loss of spatial awareness, face recognition, and artistic capabilities.

What general term describes the partial or complete loss of speech?

Aphasia

If Broca's area is affected by a stroke, will sentence assembly or word pronunciation be impaired?

The ability to pronounce words (motor speech) will be affected.

In which cerebral lobe is Broca's motor speech area situated?

Frontal lobe

What is the primary functional area located within the postcentral gyrus?

Primary somatosensory cortex

Which cortical speech area is situated near the junction of the temporal and parietal lobes and is responsible for language comprehension?

Wernicke's area

Which cerebral lobe contains the primary visual cortex?

Occipital lobe

What sulcus separates the frontal lobe from the parietal lobe?

Central sulcus

Which brainstem structure sits inferior to the pons and is continuous with the spinal cord?

Medulla oblongata

In the sagittal view of the brain, what prominent C-shaped tract of white matter lies superior to the lateral ventricles?

Corpus callosum

What egg-shaped diencephalic structure serves as the main sensory relay station?

Thalamus

What diencephalic region lies inferior to the thalamus and regulates body temperature, thirst, and hormone release?

Hypothalamus

What endocrine gland rests in the sella turcica and is connected to the hypothalamus?

Pituitary gland

What narrow canal passes through the midbrain to connect the third and fourth ventricles?

Cerebral aqueduct

What bulging brainstem region is situated between the midbrain and the medulla oblongata?

Pons

What small diencephalic gland secretes melatonin to regulate sleep cycles?

Pineal gland

What midbrain structure consists of four colliculi responsible for visual and auditory reflexes?

Corpora quadrigemina

What ventricle is situated between the pons, medulla, and cerebellum?

Fourth ventricle

What is the branching pattern of white matter in the cerebellum called?

Arbor vitae

Which cranial nerve transmits visual sensory input from the retina to the brain?

Optic nerve (CN II)

Is the optic nerve sensory, motor, or both?

Sensory