Exam 4 Review PDF

**Exam 4 Review** **Brain Anatomy and Nervous Tissue** **1.** **Identify the gross anatomy of the [externa]l brain** (i.e., each lobe and the important sulci/gyri). Be able to do so on a [cadaver brain, brain model and brain image]. a. **What are their functions?** [Lobes of the Cerebrum]...

**Exam 4 Review** **Brain Anatomy and Nervous Tissue** **1.** **Identify the gross anatomy of the [externa]l brain** (i.e., each lobe and the important sulci/gyri). Be able to do so on a [cadaver brain, brain model and brain image]. a. **What are their functions?** [Lobes of the Cerebrum] - Frontal - Voluntary motor functions, motivation, planning, mood, emotion, social judgement, and aggression - Parietal - Primary site of receiving and interpreting signals of the general senses - Occipital - Principal visual center of the brain - Temporal - Hearing, smell, learning, and some aspects of vision and emotion - The Insula - Integrate and process sensory, motor and autonomic feedback from different parts of the body - The Insula is a small mass of cortex deep to the lateral sulcus, made visible only by retracting or cutting away some of the overlying cerebrum - Gyri -- thick folds - Sulci -- shallow grooves, deeper indentions between the Gyri folds  - **The Cerebellum** - Occupies posterior cranial fossa, inferior to the cerebrum and separated from it by the transverse cerebral fissure - A narrow bridge called the **vermis** connects the left and right cerebellum hemispheres - Like the cerebrum, has grooves called **sulci or fissures**, but the folds are thinner and called **folia** - (our PowerPoint calls it sulci, but from what I read online the indentions are called fissures on a cerebellum, letting you know so you don't get confused with the image) - The most distinctive neurons of the cerebellum are called **Purkinje Cells** - Helps to regulate and coordinate motor movements - **2. Identify the [internal] gross anatomy of the brain** (e.g., thalamus, hypothalamus, corpus callosum, etc.). Be able to do so on a [cadaver brain, brain model and brain image]. **a. Give a description/ what are their functions?** - **Thalamus** -- ea. Side of the brain has a thalamus, located deep, centrally within the brain. Two ovoid/ball looking masses next to each other. - Plays a key role in motor control - Input signals travel from - Cerebellum thalamic nuclei Cerebrum - Such as... - Taste, smell, hearing, equilibrium, vision, touch, pain, pressure, heat, and cold - Involved in memory and emotional functions of the limbic system - **Hypothalamus** -- forms the floor and part of the walls to the 3^rd^ ventricle, from the optic chiasm to the mammillary bodies (ventricles is where CSF circulates) - Major control center of the ENDOCRINE and AUTONOMIC NERVOUS SYSTEM - Involved in: - Homeostatic Regulation - Hormone Secretion - Autonomic Effects - Thermoregulation - Food and Water Intake - Sleep and Circadian Rhythms - Memory - Emotional Behavior and Sexual Response - **Corpus Callosum** -- A bundle of Nerve Fibers - Connects the left and right hemispheres - Permits communication between right and left hemisphere **3. What are the components that make up the [brainstem]?** - When the cerebrum and cerebellum are removed, the Brainstem remains. - In order from Rostral Caudal (up/forward back/downward) - **Midbrain** - **Pons** - **Medulla Oblongata**  **4. Name all 3 meningeal layers. Where are they located in relation to the brain and skull?** **From Most superficial to Deep** - Skull - Epidural Space - DURA MATER - Subdural Space - ARACHNOID MATER - Subarachnoid Space - PIA MATER **a. Name the space between the dura mater and skull** - Epidural Space **b. Name the space between the dura mater and subarachnoid space** - Subdural Space **5. What factors determine [how fast an axon can conduct action potentials]?** - The conduction speed of nerve fibers depends on 2 factors: - The DIAMETER of the fiber - Signal conduction occurs on the surface (not deep within its axoplasm) - Large fibers have more surface area and conduct signals more rapidly than small fibers - Presence or Absence of MYELIN - Myelin Speeds up conduction **6. What are the divisions of the nervous system? Name them all.** [The Central Nervous System] - Brain and Spinal Cord - Processes information and Issues Commands [The Peripheral Nervous System] - **Sensory (Afferent) Division** Effectors to CNS - Somatic sensory - Receptors in skin, muscles, bones and joints to CNS - Visceral sensory - Receptors from viscera of thoracic and abdominal cavity carries signals to CNS - **Motor (Efferent) Division** CNS to Effector - Somatic motor - Carries signals from CNS to effectors (specifically skeletal muscle) - Visceral Motor -- Autonomic Nervous System - Carries signals from CNS to effectors (glands, cardiac or smooth muscle) - The Sympatric Division - Acts in synchrony with our emotion -- fight, flight, and fright - The Parasympathetic Division - Slows heart rate, increase bowl contraction a. **Differentiate between a sensory and motor neuron.** - Previously learning about the neuromuscular junction, and the excitation coupling process -- we are familiar with the motor neuron. So, notice the differences from the images below. - Sensory Neuron - Long dendrites - Short axon - Functions to conduct impulses from sensory receptors to the central nervous system - Motor Neuron - Short dendrites - Long axon - Functions to conduct impulses to an effector (muscle or gland) from the CNS  **7. Name the functions of each glial cell** - Glial Cells aka Neuroglia Cells -- protect and assist the neurons. They are "supportive" cells that protects the neurons and aids it their function. - Bind Neurons together, providing framework - Glial cells cover non-synaptic areas between neurons to prevent transmissions of unwanted signals - **Type of Neuroglia:** - [CENTRAL NERVOUS SYSTEM] - **Astrocytes -** Starlike, most abundant type (\>90%) - Forms a supportive framework - Essential for the formation and maintenance of the blood brain barrier - In Response to Trauma: - Forms Glial Scars - Astrocytes will form scars in response to injury of CNS, the bodies mechanism to protect and begin the healing process of the nervous system - Astrocytosis - The number of Astrocytes will increase, filling the space of damaged neurons - **Microglia** -- defensive immune cells of the CNS - Small macrophages that develop from white blood cells called Monocytes - **Ependymal Cells** -- lines CSF-filled cavities, resembles cuboidal epithelium, rather lining the internal cavities of the brain and spinal cord - Produces CSF - A liquid that "bathes" the CNS and fills its internal cavities - Circulates CSF - Their Cilia, located on the cells apical surface, "sweeps" the CSF - **Oligodendrocytes** -- has processes that forms myelin sheaths around CNS nerve fibers - Insulates the nerve fiber from the extracellular fluid - [PERIPHERAL NERVOUS SYSTEM ] - **Schwann Cells** -- envelops nerve fibers of the PNS - AKA neurilemmocytes - Produces a myelin sheath similar to the one produced by oligodendrocytes in the CNS - Assist in the regeneration of damaged fibers - **Satellite Cells** -- surrounds the neurosomas (cell bodies of neurons) in ganglia of the PNS - Provides electrical insulation around the soma - Regulates the chemical environment of the neuron **8. Given a Neuron, identify the major microanatomical structures** (e.g., soma, dendrites, myelin, etc.) - Soma - Neurosoma, the cell body - Contains nucleus and organelles - Dendrites - Branched processes that receive signals from other cells - Axon - Axon Hillock -- where the axon (nerve fiber) originates - Node of Ranvier - Space between myelinated Schwann cells upon the axon - Oligodendrocytes - A type of glia found in the CNS, wraps around the axon and produces myelin - Schwan Cells - A type of glia cell found in PNS, wraps around the axon and produces myelin - Myelin - Surrounds the length of an axon as a "sheath," increasing the speed of signal transmission - Axoplasm - The cytoplasm of an axon - Axolemma - The membrane of an axon **a. What are the names of the myelin cells in the CNS vs PNS?** - CNS OLIGODENDROCYTES - PNS SCHWANN CELLS **9. What are the components of the diencephalon?** - **Thalamus** - Subthalamus & Metathalamus - not identified on powerpoint - **Hypothalamus** - Above pituitary gland - **Epithalamus** - Where the PINEAL GLAND is found - Involved in circadian rhythms - The Habenula - A relay from the limbic system to the midbrain (of brainstem) - Forms wall of third ventricle **10. What is the protective barrier that selectively allows substances into the brain, like: oxygen, carbon dioxide, nicotine, alcohol, drugs, caffeine, anesthesia.** - The Blood-Brain Barrier (BBB) - Consists of tight junctions between the endothelial cells that form the capillary walls **Spinal Cord and Reflexes** 1\. What is the name of reflexes you are born with? - Inborn **(intrinsic**) reflex rapid, predictable motor response to a stimulus - Unlearned, unpremeditated, and involuntary - Built into our neural anatomy regulated by the brain steam and spinal cord - Learned **(acquired)** reflex results from practice or repetition - Ex. Driving a car to school 2. Identify the major anatomical structures of a nerve. Be able to identify them in an image. 3\. Given a cross-section of a spinal cord, identify the major anatomical structures (e.g., gray matter, white matter, ventral horn, etc.)  **4. Be able to identify the nerve plexus that innervates each major area of the body** **a. Head, neck, shoulder, legs, arms, thorax.**   **Cranial Nerves and Special Senses** **1. For each cranial nerve, know the name, number, where it innervates and what they control/sense.** +-----------------+-----------------+-----------------+-----------------+ | Cranial | Name | Innervation | Control / Sense | | | | | | | Nerve | | | | +=================+=================+=================+=================+ | I | Olfactory | The olfactory | sensory | | | | mucosa within | | | | | the nasal | | | | | cavity | | | | | | | | | | (olfactory | | | | | bulb) | | +-----------------+-----------------+-----------------+-----------------+ | II | Optic | The retina of | sensory | | | | the eye and | | | | | brings visual | | | | | information to | | | | | the brain | | +-----------------+-----------------+-----------------+-----------------+ | III | Oculomotor | Moves eye | motor | | | | medially | | +-----------------+-----------------+-----------------+-----------------+ | IV | Trochlear | Depresses eye | motor | | | | and turns it | | | | | laterally | | +-----------------+-----------------+-----------------+-----------------+ | V | Trigeminal | the face | mainly sensory | +-----------------+-----------------+-----------------+-----------------+ | VI | Abducens | Moves eye | motor | | | | laterally | | +-----------------+-----------------+-----------------+-----------------+ | VII | Facial | Sensory | sensory and | | | | | motor | | | | Motor | | +-----------------+-----------------+-----------------+-----------------+ | VIII | Vestibulocochle | [Vestibular | sensory | | | ar | branch]{.underl | | | | | ine} | | | | (auditory) | detect | | | | | movements that | | | | | are linear and | | | | | angular | | | | | (turning) | | | | | | | | | | [Cochlear | | | | | branch]{.underl | | | | | ine} | | | | | responsible for | | | | | hearing sounds | | +-----------------+-----------------+-----------------+-----------------+ | IX | Glossopharyngea | [Sensory]{.unde | sensory and | | | l | rline} | motor | | | | neurons for | | | | | taste to | | | | | posterior 1/3 | | | | | of tongue, | | | | | sensory neurons | | | | | of pharynx and | | | | | eardrum | | | | | | | | | | [Motor]{.underl | | | | | ine} | | | | | stylopharyngeus | | | | | muscle | | | | | (swallowing) | | | | | and parotid | | | | | salivary glands | | +-----------------+-----------------+-----------------+-----------------+ | X | Vagus | [Sensory]{.unde | sensory and | | | | rline} | motor | | | | pharynx, | | | | | external | | | | | acoustic | | | | | meatus, | | | | | diaphragm, and | | | | | internal organs | | | | | of the thoracic | | | | | and | | | | | abdominopelvic | | | | | cavities | | | | | | | | | | [Motor]{.underl | | | | | ine} | | | | | motor fibers to | | | | | the palate, | | | | | pharynx, and | | | | | autonomic motor | | | | | fibers to | | | | | internal organs | | +-----------------+-----------------+-----------------+-----------------+ | XI | Accessory | Trapezius and | motor | | | | Sternocleidomas | | | | | toid | | +-----------------+-----------------+-----------------+-----------------+ | XII | Hypoglossal | muscle that | motor | | | | moves tongue | | +-----------------+-----------------+-----------------+-----------------+ | | | | | +-----------------+-----------------+-----------------+-----------------+ **2. What is the diagnosis for inflammation of the middle ear?** - Otitis Media middle ear inflammation - Common result of a sore throat - Most [common cause of hearing loss in children] - [Eardrum bulges and becomes inflamed and red] - Antibiotics used for treatment **3. When a person is color blind, what happens to the cell populations of the retina? Hint: there are 2 specific cells that are impacted here.** - **The photoreceptors**: - Rods dim light (night vision) - Cones color (day vision) - A [lack of one or more cone cells] will mean the eye cannot detect color **4. Identify the extrinsic muscles that control the eye** Innervated by... - Lateral Rectus moves eye laterally VI - Medial Rectus moves eye medially III - Superior Rectus elevates/ turns medially III - Inferior Rectus depresses/ turns medially III - Inferior Oblique elevates/ turns laterally III - Superior Oblique depresses eye and turns it laterally IV  **5. Identify the anatomy of the pinna and inner ear structures**  **a. Where is earwax made? What is the scientific name for this wax?** - In the [External Acoustic Meatus] (auditory canal) of the External Ear - Ceruminous glands will secrete CERUMEN (earwax) **6. How does the virus causing shingles enter the body? What happens when it reactivates?** (Lab 9 PowerPoint) - Through a common disease in early childhood -- Chickenpox (varicella-zoster virus) which will remain for life in the posterior root ganglia - If the immune system is compromised, the virus can travel along the sensory nerve fibers by fast axonal transport causing Shingles (herpes zoster) **a. Give some symptoms that are associated with shingles diagnoses** - Painful trail of skin discoloration. Fluid filled vesicles along the path of the nerve **7. Identify the gross anatomy of the eye on the external and internal aspects. What does each part do?** - Lacrimal Apparatus - Lacrimal gland of apparatus produces tears  - Three Layers (tunics) that form the wall of the eyeball - Retina - Photoreceptors - Attached to the rest of the eye only at Optic Disc and at Ora Serrata (see right 3^rd^ pic) - Macula Lutea - Patch of cells on visual axis of eye - Fovea Centralis - Pit in center of macula lutra - Choroid - Vascular - Brown (melanocytes) - Sclera - White - Fibrous connective tissue - Avascular RETINA OF THE EYE  **8. What cell types are found in the retina? What is their function?** - Outer layer pigmented cells - Inner Layer (neural) - Photoreceptors - Rods dim light (night vision) - Cones color (day vision) - Bipolar Cells - Ganglion Cells - The axons of the ganglion cells converge at the posterior aspect of the eyeball and exit as the optic nerve  **9. Name the diagnosis that explains elevated inner eye pressure that could cause blindness.** - Glaucoma -- elevated pressure within the eye due to obstruction of scleral venous sinus and improper drainage of aqueous humor. - This leads to a death of retinal cells due to compression of blood vessels and lack of oxygen **10. What structure converts chemicals in the saliva to signals that we perceive as taste?** - Gustatory epithelial cells -- taste buds **11. What is the diagnosis for inflammation in the middle ear? What about inflammation of the external auditory canal?** - [Middle Ear] Inflammation - Otitis Media - Common result of a sore throat - Most common cause of hearing loss in children - Eardrum bulges and becomes inflamed and red - Antibiotics used for treatment - [External Auditory Canal] inflammation - Otitis Externa - Redness and swelling within the tube between the outer ear and eardrum - Referred to as "swimmers' ear" because repeated exposure to water can make the ear canal more vulnerable to inflammation **12. What structure is important for reception of sound for our sense of hearing?** - Cochlear Branch