Lab 3 Flashcards
Fornix
- Is an arching, fibrous band of nerve fibers that extend from the hippocampus to the mamillary body of the hypothalamus
- An archlike anatomical structure or fold, such as the arched band of white matter located beneath the corpus callosum of the brain.
Septum Pellucidum
A thin membrane of nervous tissue that forms the medial wall of the lateral ventricles in the brain
Development of the the neural tube from embryonic ectoderm
1) The neural plate forms from surface ectoderm.
2) the Neural plate invaginates, forming the neural groove flanked by neural folds.
3) Neural fold cells migrate, form the nural crest, will form much of the PNS and other surfaces.
4) the Neural groove becomes the neural tube, which will form CNS structures.
Gray matter
Neuron cell body clusters
White matter
Nerve fibers = (myelinated axons)
Basal Nuclei (def. location, function)
- Are densely packed locations of cell bodies (somas) in the subcortical area (beneath the cortex) of the brain. Gray matter
- Nuclear bodies are in the CNS.
- Important in starting, stopping, and monitoring the intensity of movements executed by the cortex
Basal Ganglia (def. location)
- Are the cluster of neuron cell bodies and dentrites.
- Located in the PNS. Ex. the dorsal root ganglions that exit each vertabrae at the intervertebral foramen
Brain function
Sensory — Integration —– Motor
4 Major parts of the brain
- Brain stem (medulla oblongata, pons, midbrain)
- Diencephalon (thalamus, hypothalamus)
- Cerebrum (83% of brain mass)
- Cerebellum (little brain)
Major lobes of cerbrum
- Frontal lobe (1)
- Parietal lobes (2)
- Temporal Lobes (2)
- Occipital lobe (1)
- Insula
Gustatory cortex (taste) location
In Insula
Specific sulci / fissures
- Central sulcus
- Lateral / Sylvian sulcus
- Transverse fissure
- Longitudinal fissure
Extensions of Dura Matter
- Tentorium cerebelli (separartes occipital lobe from cerebellum)
- Falx cerbelli (separates cerebellar hemispheres)
- Falx cerebri (separates the 2 hemispheres of the brain)
Connetion of the 2 hemispheres
Corpus callosum
Outer cortex of brain (compossition and characteristics)
- Gray matter surrounds an interior that is mostly white matter, except for a few small protions (basal nuclei)
- Surface is marked by ridges called gyri separated by grooves called sulci
Cerebrum divisions
internally each hemispheres is divided into 3 regions.
- Superficial cortex of gray matter
- Cerebral cortex - outermost layer of gray matter
- Makes up superficial area and functional areas
- Contains 70% of the neurons in CNS
- Internal white matter
- Basal nuclei (islands of gray matter deep within the white matter)
Cerebral cortex functions
- Sensory: allow for conscious recognition of stimuli
- Motor: Control voluntary, motor functions
- Association: integration
Broca’s area
- Region of the brain that contains motor neurons involved in the control of speech.
- This area, located in the frontal part of the left hemisphere of the brain,
Wernicke’s area
- Region of the brain that contains motor neurons involved in the comprehension of speech.
- The Wernicke area is located in the posterior third of the upper temporal convolution of the left hemisphere of the brain.
- Damage to the temporal lobe may result in a language disorder known as Wernicke aphasia.
- An individual with Wernicke aphasia has difficulty understanding language; speech is typically fluent but is empty of content and characterized by circumlocutions, a high incidence of vague words like “thing,” and sometimes neologisms and senseless “word salad.”
Commisural fibers
- Connect corresponding gray areas of the two hemispheres, enabling them to function as a coordinate whole (includes the copus callosum)
- Connect corresponding gray areas of the two hemispheres, enabling them to function as a coordinate whole (includes the copus callosum)
Commisural fibers
Association fibers
- Connect different parts of the same hemisphere
Projection fibers
- Nerve fibers that connect the cerebral cortex with the subcortical centers, the brain stem, and the spinal cord’
Reversed
- Connect different parts of the same hemisphere
Association fibers
Reversed
- Nerve fibers that connect the cerebral cortex with the subcortical centers, the brain stem, and the spinal cord’
Projection fibers
Midbrain (functions)
- The midbrain is the smallest region of the brain that acts as a sort of relay station for auditory and visual information.
- The midbrain controls the visual and auditory systems as well as eye movement.
- Portions of the midbrain called the red nucleus and the substantia nigra are involved in the control of body movement.
- The darkly pigmented substantia nigra contains a large number of melanin-producing neurons are located (melanin is a precursor for dopamin). The degeneration of neurons in the substantia nigra is associated with Parkinson’s disease.
Reticular Formation (location, action)
- It extends from the central core of the medulla oblongata, pons and midbrain.
- Controls brain alertness; it is inhibited by sleep, alcohol, tranquilizers
Limibic System
- Limbus = “ring”
- group of subcortical structures (e.g. hypothalamus, hyppocampus and the amygdala)
- Involved in olfaction, emotion, behavior, and various autonomic functions.
Midbrain (anatomy)
- Corpora quadrigemina: composed of
- Superior coliculi (visual reflexe center that coordinate head and eye movement)
- Inferior coliculi (auditory relay from hearing receptors to sensory cortex)
- Substantia nigra: contains high [] of melanin pigment which is a precursor of dopamine.
- Functionally linked to basal nuclei (putamen)
- damage to sustantia nigra = Parkinson’s disease.
Flaccid paralysis
Damage of ventral horn neurons, or ventral roots –> nerve impulses don’t reach muscles, thus not move voluntary or involuntary –> muscle atrophy
Spastic paralysis
Damage in the neurons of the primary motor cortex. Spinal reflexes continue to stimulate muscle irregularly. Muscles remain healthier longer but no voluntary control.
paralysis
Any localized damage to the spinal cord or its roots leads to paralysis (loss of motor function)
paresthesias
Any localized damage to the spinal cord or its roots leads paresthesias (loss of sensory function).
Paralysis vs Paresthesias
Any localized damage to the spinal cord or its roots leads to paralysis (loss of motor function) or paresthesias (loss of sensory function).
Region that contains part of the system that helps maintain cerebral alertness and regulates skeletal and visceral muscle activity. (location)
Reticular Formation (medulla oblongata, ponds, midbrain)
• Reticular Formation (location, function)
- medulla oblongata, ponds, midbrain
- Region that contains part of the system that helps maintain cerebral alertness and regulates skeletal and visceral muscle activity
• Reticular Formation (location, function)
- medulla oblongata, pons, midbrain
- Region that contains part of the system that helps maintain cerebral alertness and regulates skeletal and visceral muscle activity
Monocytes
o 3-9% of total WBC’s;
o phagocytosis;
o largest WBC, 12-20 microns,
o Large kidney shaped nucleus.
o increased during typhoid fever, malaria, and mononucleosis.
Monocytes are the leukocyte that is the most problematic for identification, because they can be fairly variable in size and appearance. They are often larger than neutrophils and are usually the largest leukocyte. The nucleus can be round to kidney-shaped to pseudo-lobulated (can mimic a neutrophil). It can may be confused with band neutrophils. However, the chromatin of monocytes is less dense than neutrophils, and is described as lacey to slightly clumped. The cytoplasm is usually smooth and blue-grey and may contain a few variably-sized vacuoles, and occasionally a few very fine pink-red granules. They are also larger than neutrophils
Monocytes
o 3-9% of total WBC’s;
o phagocytosis;
o largest WBC, 12-20 microns,
o Large kidney shaped nucleus.
o increased during typhoid fever, malaria, and mononucleosis.
Monocytes are the leukocyte that is the most problematic for identification, because they can be fairly variable in size and appearance. They are often larger than neutrophils and are usually the largest leukocyte. The nucleus can be round to kidney-shaped to pseudo-lobulated (can mimic a neutrophil). It can may be confused with band neutrophils. However, the chromatin of monocytes is less dense than neutrophils, and is described as lacey to slightly clumped. The cytoplasm is usually smooth and blue-grey and may contain a few variably-sized vacuoles, and occasionally a few very fine pink-red granules. They are also larger than neutrophils
Fetal circulation bypass structures (shunts) in the heart.
- Foramen Ovale –> Fossa ovalis (bypass the lungs)
- Ductus arteriosus –> Liagmentum arteriosum (moves blood from the pulmonary artery to the aorta)
WBC order from most to least abundant
(Never Let Monkeys Eat Bananas)
Neutrophils (Granulocytes)
Lymphocytes (Agranulocyte)
Monocyte (Agranulocyte)
Eosinophils (Granulocytes)
Basophils (Granulocytes)
Agranulocytes
- Monocytes
- Lymphocytes
Basophils
- granulocytes,
- least common of the granulocytes, 0.01% to 0.3%
- Are basophilic, they are susceptible to staining by basic dyes. Partially constricted into two lobes, and with cytoplasm containing coarse bluish-black granules of variable size.
- large cytoplasmic granules which obscure the cell nucleus under the microscope.
- Store histamine
- involved in inflammatory reactions in your body, especially those related to allergies and asthma.
Heart strings.
Cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve
chordae tendineae
Basophils
- granulocytes,
- least common of the granulocytes, 0.01% to 0.3%
- Are basophilic, they are susceptible to staining by basic dyes. Partially constricted into two lobes, and with cytoplasm containing coarse bluish-black granules of variable size.
- large cytoplasmic granules which obscure the cell nucleus under the microscope.
- Store histamine
- involved in inflammatory reactions in your body, especially those related to allergies and asthma.
Lymphocytes
o 25-33% of total WBC’s;
o live for several months to years;
o range in size from large (10-14μ) to small (6-9μ);
o attack cells directly
- T-cells are involved in cell-mediated immunity. In the thymus, T cells multiply and differentiate into helper, regulatory, or cytotoxic T cells or become memory T cells.
- B-cells are involved in so-called humoral immunity; on encountering a foreign substance (antigen), the B lymphocyte differentiates into a plasma cell, which secretes immunoglobulin (antibody).
Granulocytes
- Neutrophils
- Eosinophils (red granules)
- Basophils (dark blue granules)
Neutrophils
o most abundant WBC = 54%-62%;
o polymorphonucleocytes (PMN);
o phagocytosis of foreign particles (disease organisms & debris);
o increased in acute bacterial infections.
Eosinophils
o 1-3% of total WBC’s;
o kill parasites and are responsible for allergic reactions;
o increased during parasitic infections (tapeworm, hookworm);
o Release toxic proteins during allergic reactions.
- Appear brick-red after staining with eosin, a red dye
- Eosinophils gather wherever there is a parasite infection or an allergic reaction such as allergic asthma, and then release their toxins. The toxins are very efficient at harming parasites, but unfortunately will also harm us if released in the wrong place. So the lining of the lungs becomes damaged in asthma, and one of the most important purposes of asthma treatment is to prevent this damage.
Region that contains part of the system that helps maintain cerebral alertness and regulates skeletal and visceral muscle activity. (location)
Reticular Formation (medulla oblongata, pons, midbrain)
Eosinophils
o 1-3% of total WBC’s;
o kill parasites and are responsible for allergic reactions;
o increased during parasitic infections (tapeworm, hookworm);
o Release toxic proteins during allergic reactions.
- Appear brick-red after staining with eosin, a red dye.
- Eosinophils gather wherever there is a parasite infection or an allergic reaction such as allergic asthma, and then release their toxins. The toxins are very efficient at harming parasites, but unfortunately will also harm us if released in the wrong place. So the lining of the lungs becomes damaged in asthma, and one of the most important purposes of asthma treatment is to prevent this damage.
Science of Blood Vessels
Angiology (Angeon = vessels)
Branches of the aorta (elastic arteries)
- Ascending Aorta
- Left and right coronary artery
- Brachiocephalic
- Arch of Aorta
- Right subclebian
- Rigth common carotid artery
- Left common carotid artery
- Left subclebian
chordae tendineae
Heart strings.
Cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve
Neutrophils
o most abundant WBC = 54%-62%;
o polymorphonucleocytes (PMN);
o phagocytosis of foreign particles (disease organisms & debris);
o increased in acute bacterial infections.
Agranulocytes
- Monocytes
- Lymphocytes
Lymphocytes
o 25-33% of total WBC’s;
o live for several months to years;
o range in size from large (10-14μ) to small (6-9μ);
o attack cells directly
- T-cells are involved in cell-mediated immunity. In the thymus, T cells multiply and differentiate into helper, regulatory, or cytotoxic T cells or become memory T cells.
- B-cells are involved in so-called humoral immunity; on encountering a foreign substance (antigen), the B lymphocyte differentiates into a plasma cell, which secretes immunoglobulin (antibody).
First branches of the aorta
(Take care of yourself first then of others)
Right and left Coronary Arteries (heart takes care of itself first)
Meninges in PNS
1) Dura Mater: outermost layer
2) Arachnoid mater: thin and wispy
3) Pia mater: bound tightly to surface.
Pia mater
- Forms the Filum Terminale (anchors spinal cord to coccyx)
- Forms the denticulate ligaments that attache the spinal cord to the dura mater
Epidural space
- Spinal epidural is done between L3 and S1
- Spinal tap or epidural is done to inject medications into the cerebrospinl fluid, particularly for spinal anesthesia or chemotherapy
- Epidural is don to collect cerebrospinal fluid, particularly for spinal when meningitis is suspected.
- Between the bony vertebrae and spinal dura mater; filled with soft padding of fat and a network of veins
Subdural space
- Filled with Serous fluid
- The space appears to be widest in the cervical region
- however, that the spinal subdural space is not a “potential” space at all, but that it occurs as a result of tissue damage which creates a cleft in this area of the meninges
Superior Sagittal Sinus
- CSF is absorbed into the dural venus sinuses via the arachnoid villi.
- dural venus sinuses collect venous blood from the brain and direct it into the internal jugular veins of the neck. It has no valves.
Arachnoid villi
- knoblike projections of the arachnoid mater that protude superiorly through the dura mater into the superior sagittal sinus.
- This villi absorb CSF into the venous blood of the sinus
reversed
tough fibrous sheath around a nerve
Epineurium
Loose connective tissue that encloses axons and their myelin sheaths
Endoneurium
What is the largest cranial nerve?
Which parts of the body it innervate?
• Nerve V, The Trigeminal nerve,
- The ophthalmic nerve (V1) carries sensory information from the scalp and forehead, the upper eyelid, the conjunctiva and cornea of the eye, the nose.
- The maxillary nerve (V2) carries sensory information from the lower eyelid and cheek, the upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses.
- The mandibular nerve (V3) carries sensory information from the lower lip, the lower teeth and gums, the chin and jaw, parts of the external ear. The mandibular nerve carries touch/position and pain/temperature sensation from the mouth. It does not carry taste sensation. The motor root of the mandibular nerve innervates the four muscles of mastication.
Spinal nerves in the:
- Cervical region
- Thoracic region
- Lumbar region
- Sacral region
- Coccygeal region
- 8 Cervical (C1 - C8)
- 12 Thoracic (T1 -T12)
- 5 Lumbar (L1 - L5)
- 5 Sacral (S1 - S5)
- 1 Coccygeal (Co1)
Cervical plexus
(most of its branches are cutaneous nerves)
Cervical plexus (C1 to C5)
- Cutaneous branches:
- a. Lesser occipital (C2, C3): posterior head and neck
- b. Greater auricular (C2, C3): ear, parotid gland
- c. Transverse cervical (C2, C3): anterior neck
- d. Supraclavicular (C3-C4): shoulder
- Motor branches:
- a. Ansa cervicalis (C1-C3): Infrahyoid muscles of neck
- b. Segmental and other muscular branches (C1-C5) : deep muscles of neck (scalenes, trapezius, sternocleidomastoid)
- c. Phrenic (C3-C5): Diaphragm
Brachial plexus
Brachial plexus (C5 to T1)
- Muscolocutaneous nerve (C5-C7): biceps brachii, brachialis
- Median nerve (C8, T1, C5-C7): Flexors (carpi radialis), pronator teres, Thenar muscles
- Ulnar nerve (C8, T1): Flexor (carpi ulnaris), hypothenar muscles
- Radial nerve (C5-C8, T1): Triceps brachii, extensors
- Axillary nerve (C5, C6): Deltoid, Teres minor
Lumbar plexus
Lumbar plexus (L1 to L4)
- Femoral nerve (L2-L4): Iliacus, sartorius, rectus femoris, pectineus, vastus (lateralis, medialis, intermedius)
- Obturator nerve (L2-L4): Adductur (magnus, brevis, longus), Gracilis, pectineus, obturator externus
Sacral plexus
Sacral plexus (L4 to S4)
- Sciatic nerve
- a. Tibial nerve (L4-S3): biceps femoris, semitendinosus, adductor magnus, semimembranosus, gastrocnemius, soleus, Flexors
- b. Common fibular nerve (L4-S2): Biceps femoris, tibialis anterior, extensors
- Superior gluteal
- Inferior gluteal
- Posterior femoral cutaneous
- Pudendal (S2-S4) most of skin and muscles of perineum (anus, clitoris, labia, vaginal, penis, scrotum
