Anatomy Lab – Test 1

Back○ Objectives

The surface landmarks of the back. The parts and details of the bony vertebral column, scapula, iliac crest and posterior skull as given on pages 4-

6. Muscles of the superficial, intermediate and deep back proximal and distal attachments, actions and

innervations. The greater occipital nerve (specifically) and recognize the segmental arrangement of the cutaneous branches

of other dorsal primary rami. The contents of the vertebral canal as detailed on pages 12-14.

○ Structures Muscles:

Superficial○ Trapezius – has three parts and three distinct actions○ Latissimus dorsi○ Rhomboid major and minor – separation not very obvious, must be distinguished by distal attach○ Levator scapulae

Serratus posterior superior Serratus posterior inferior Splenius capitis and cervicis – deep to trap, go obliquely across the neck○ Cervicis is on the outside

Semispinalis capitis – one of the transversospinal muscles, can be identified at base of skull○ Greater occipital nerve passes through here○ Rotates to opposite side

Erector spinae (3 parts)○ Iliocostalis – most lateral○ Longissimus○ Spinalis – most medial

Nerves: Greater occipital nerve – is the dorsal ramus of spinal nerve C2○ Pierces the trapezius right near the skull at the level of the ears

Accessory nerve – can be seen deep to the trapezius Dorsal ramus Ventral ramus Spinal nerve

Arteries: Occipital artery – accompanies the greater occipital nerve Transverse cervical artery – accompanies the accessory nerve and the C3 & C4 branches

Other: Thoracolumbar fascia Triangle of auscultation○ above, by the Trapezius○ below, by the Latissimus dorsi○ laterally by the medial margin of the scapula

Lumbar triangle - medially by the latissimus dorsi muscle; laterally by the external abdominal oblique muscle; and inferiorly by the iliac crest

Spinal cord:

Epidural space Dural sac, dura mater Arachnoid mater Subarachnoid space Denticulate ligaments Ventral and dorsal roots Dorsal root ganglion (spinal ganglion) Conus medullaris Cauda equina Filum terminale

Vertebrae: Atlas Axis Thoracic vertebra Lumbar vertebra Spinous and transverse processes Laminae and pedicles Articular processes – join to connect two vertebrae dorsal to the spinal cord Vertebral arch Vertebral foramina Intervertebral foramen Vertebral foramen Transverse foramen (cervical only) – where vertebral artery passes through

Scapula: Spine Acromion Lateral and medial borders – self explanatory Superior and inferior angles – topmost and bottommost points of scapula

Shoulder○ Objectives

Identify the bony landmarks of the shoulder. Identify the muscles, nerves, vessels and ligaments indicated in the shoulder region (pgs 18-19).

○ Structures Muscles:

Scapulohumeral○ Deltoid – axillary nerve and posterior circumflex humeral artery should be seen on the deep surface near

attachment to humerus○ Teres minor – also innervated by the axillary nerve (it is pretty close to the deltoid)○ Teres major○ Supraspinatus – suprascapular artery and suprascapular nerve found deep to here AND Infraspinatus by

going around greater scapular notch○ Infraspinatus○ Subscapularis – not dissected here

Triceps brachii Nerves:

Axillary Other:

Suprascapular ligament – army goes over the bridge, navy goes under Quadrangular space – teres minor, teres major, lateral and long head of tricep○ Contains axillary and posterior circumflex humeral

Triangular space – teres minor, teres major, lateral head of tricep

○ Contains circumflex scapular artery deep to it (not through) Vessels:

Thoracoacromial artery (and branches) Posterior humeral circumflex artery Deep brachial artery (profunda brachii) – found in trigular hilus

Axilla○ Objectives

Identify muscles, nerves and vessels indicated in the pectoral region (pgs. 43-46). Identify the boundaries and contents of the axilla as indicated on pgs. 19-22. Identify all of the branches of the axillary artery. Identify all of the infraclavicular parts of the brachial plexus (cords, divisions and terminal branches).

○ Structures Muscles

Pectoralis major and minor Serratus anterior – upper 8 ribs in front, to medial border of scapula (so it wraps around) Latissimus dorsi Subclavius Teres major Subscapularis

Blood Vessels Cephalic vein – between deltoid and pec major in the deltopectoral triangle Pectoral branch of thoracromial artery – can travels with pectoral nerves in pecs? Axillary Artery – continuation of subclavian. Contains 3 parts○ Note – branches are named by their distribution, not origin (due to variance)○ Part 1 – superior thoracic artery○ Part 2

Thoracromial artery – branch of axillary artery in 2nd part right behind pec minor○ Clavicular branch – supplies subclavius muscle○ Acromial branch○ Deltoid branch – goes through deltopectoral groove○ Pectoral Branch –

Lateral thoracic artery – under lateral border of pec minor, not always there, another branch of axillary artery

○ Part 3 Subscapular artery – largest branch and divides into circumflex scapular, thoracodorsal artery○ Thoracodorsal artery travels with thoracodorsal nerve

Anterior and posterior circumflex arteries – posterior is larger○ Posterior circumflex goes through quadrangular space, travels with axillary nerve○ Both travel laterally

Nerves: The cords of the brachial plexus are named according to their relationship to the second part of the axillary

artery Musculocutaneous nerve – use it to help find the lateral cord○ Lateral cord also produces lateral root of the median nerve, which connects to the median nerve

Median nerve can help you find median cord via the medial root of the median nerve○ Medial cord → medial cutaneous nerve of the forearm and medial cutaneous nerve of the arm

Posterior cord produces axillary, radial and the three subscapular (upper, middle, lower) nerves○ The subscapular nerves run on the anterior surface of the subscapularis muscle and innervates the three

muscles that form the posterior wall of the axilla

○ Axillary nerve passes posterior to the humerus and courses through the quadrangular space with the posterior circumflex humeral artery

Medial pectoral – deep to the surface of each pec○ Off of medial cord

Lateral pectoral – deep to the surface of each pec○ Off of lateral cord

Radial Suprascapular Long thoracic nerve -

Other clavipectoral fascia – immediately deep to the pect major axillary sheath – CT that surrounds axillary vessels and brachial plexus○ boundaries are the same as the axillary artery

Arm and Flexor Forearm○ Objectives

The structures listed in the cubital fossa, posterior and anterior fascial compartments of the arm as indicated on pgs. 22-30.

The bony landmarks of the arm. The structures of the forearm highlighted on pgs. 26-29. The bony landmarks of the forearm.

○ Structures ARM

Muscles:○ Brachioradialis○ Coracobracialis○ Biceps brachii – tendon of long head of biceps brachii goes through intertubercular sulcus posterior to

the transverse humeral ligament○ Brachialis – deep to bicep brachii○ Triceps – between the long head and the lateral head is an opening in which you can see the radial nerve

and the deep artery of the arm This is the triangular hilus/interval

Nerves:○ Axillary○ Median – goes in intermuscular septum on medial side of arm

Goes through cubital fossa Does not innervate muscles in the arm

○ Musculocutaneous – innervates all three muscles of anterior compartment Enters coracobrachialis → goes between bicep and brachialis Continues as Lateral cutaneous nerve of the forearm

○ Medial cutaneous nerve of the forearm – comes from brachial plexus, follows basilic vein?○ Radial – deep to the triceps and lies directly on the posterior surface of the humerus in the radial groove

Innervates all muscles in the posterior compartment○ Ulnar – goes over medial epichondyle

Does not innervate muscles in the arm○ Upper, lower and middle subscapular

Vessels:○ Basilic vein○ Brachial artery – continuation of axillary artery, begins at inferior border of teres major

In Arm – branches into deep artery of the arm, superior ulnar collateral artery, inferior ulnar collateral artery

At Elbow - Branches into radial artery and ulnar artery○ Cephalic vein○ Deep brachii artery – on lateral side of the arm (makes sense since it goes out with radial○ Median cubital vein

Other:○ Bicipital aponeurosis and tendon

FLEXOR FOREARM Muscles:○ Superficial flexors

Flexor carpi radialis Flexor carpi ulnaris Flexor digitorum superficialis – located deep to the other four muscles, has four tendons○ Connects to middle phalanges

Palmaris longus Pronator teres

○ Deep Flexors Flexor digitorum profundus – connects to distal phalanges Flexor pollicis longus Pronator quadratus

Nerves:○ Ulnar – passes between the two heads of the flexor carpi ulnaris○ Median – enters wrist in middle. Innervates most of the muscles in the flexor compartment

Is deep to the superficial group of flexor muscles Anterior interosseous – passes deep to the pronator quadratus

○ Radial Superficial Deep

Vessels:○ Brachial artery – branches into radial and ulnar in the cubital fossa○ Radial artery – follows radius

Can be seen at proximal forearm between brachioradialis and pronator teres○ Ulnar artery

Common interosseous – branches ○ Anterior interosseous○ Posterior interosseous

anterior ulnar recurrent artery and posterior ulnar recurrent artery – anastamose with collateral branches of brachial artery

Other:○ Interosseous membrane

Notes Path of median nerve in forearm was emphasized Path of radial nerve in arm was emphasized

Extensor Forearm and Hand○ Objectives

The bony landmarks of the hand. The structures of the palm of the hand bolded and indicated on pgs. 30-35. The structures of the extensor forearm and dorsum of the hand highlighted on pgs. 35-36.

○ Structures EXTENSOR FOREARM and HAND

Muscles:

○ Palmaris brevis – found superficial to the palmar aponeurosis What is This???○ Thenar

Abductor pollicis brevis Opponens pollicis – deep to abductor pollicis brevis Flexor pollicis brevis

○ Hypothenar Abductor digiti minimi Opponens digiti minimi – again the deepest Flexor digiti minimi

○ Deep Lumbricals Adductor pollicis Palmar interossei – 3 of them. originate on only 1 metacarpal Dorsal interossei – 4 of them. originate on 2 metacarpals

○ Snuff Box Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus

○ Superficial Group Extensor carpi radialis longus Extensor carpi radialis brevis Brachioradialis Extensor carpi ulnaris Extensor digitorum

○ Deep Group Supinator – deep to brachioradialis Extensor indicis

Vessels:○ Radial artery –

Deep palmar arterial arch○ Ulnar artery

Superficial palmar arch Nerves:○ Ulnar – divides after the pisiform bone

Deep branch – disappears into the hypothenar muscles○ also innervates the interosseous muscles

Digital branch – forms the superficial palmar arch○ Median

Recurrent branch – goes through carpal tunnel, innervates thenar muscles (and lumbrical muscles 1 and 2??)○ Crosses surface of flexor pollicis brevis

Digital branches – also goes through the carpal tunnel???○ Goes from 1 common branch for each finger, to 2 proper branches (on each side of finger)

○ Radial - goes through anatomical snuffbox. Can be found between brachioradialis and brachialis Posterior interosseous – continuation of the deep branch of the radial nerve after it emerges from the

supinator muscle○ Provides motor branches for the extensor muscles of forearm

Other:○ Transverse carpal ligament (Flexor retinaculum)○ Palmar aponeurosis – longitudinal fibers end by attaching to proximal phalanx

○ Fibrous digital sheaths – on flexor surface of each digit, contain flexor tendons○ Extensor expansion – wrapped around the dorsum and the sides of the proximal phalanx and the distal

end of the metacarpal bone. The hood-like expansion retains the extensor tendon in the midline of the digit. The tendons of the lumbrical and insterosseous muscles attach to the extensor expansion Basically just tendon on fingers

Thoracic Wall, Lungs and Pleura○ Objectives

The bony landmarks and muscles of the thoracic wall. The highlighted structures of the intercostal spaces and the isolated anterior thoracic wall (pgs. 46-48). The extent and specific features of the pleural cavities. 4. The structures of the right and left lungs as described on pages 50 and 51.

○ Structures Thoracic wall/Lungs

Note – each intercostal space is named after the rib above it Muscles:○ Pectoralis major and minor○ Serratus anterior○ External intercostal – fibers oriented like hands in pocket

Elevates rib below Becomes a membrane close to the sternum

○ Internal intercostal – fibers oriented the other way Depresses rib above Becomes membrane close to the vertebrae

○ Innermost intercostal – fibers oriented the other way Stops before mid axillary line

○ Transversus thoracis – inside of thoracic wall, origin on sternum, insertion on above ribs Nerves:○ Lateral cutaneous ○ Intercostobrachial○ Medial pectoral○ Lateral pectoral○ Phrenic – anterior to the root of the lung and deep to mediastinal pleura○ Intercostal - Supplies skin above, intercostal muscles, parietal pleura○ Sympathetic trunk

Vessels:○ Cephalic vein○ Thoracoacromial artery○ Lateral thoracic artery○ Right and Left Internal thoracic arteries – on inside of thoracic wall

Feeds anterior intercostal arteries○ Anterior intercostal artery and vein – same as posterior, just in the anterior area○ Posterior intercostal artery and vein – in the rib groove between internal and innermost intercostal

muscles○ Pulmonary artery and vein – artery is above (a little stronger) and vein is below○ Bronchial artery – smallest that can be seen in cross section of root

Courses along the surface of the main bronchus○ Pericardiophrenic vessels accompany the phrenic nerve

Other:○ Apex – in the cupula○ Parietal pleura (subdivisions) – each parietal pleura is subdivided

Costal – lines inner surface of thoracic wall Mediastinal – Diaphragmatic – sharply folded where it meets the costal pleura Cervical – extends superior to the first rib

○ Visceral pleura – at root of lung it becomes continuous with parietal pleura○ Pleural cavities○ Pleural recesses – where one portion of parietal pleura contacts the other

Costomediastinal recess – not as visible Costodiaphragmatic recess – where costal pleura contacts diaphragmatic

○ Fissures on the lungs Oblique fissure – only on right lung, 5th rib laterally to 6th costal cartilage medially Horizontal fissure – deep to 4th rib

○ Lobes of the lungs○ Root (hilus) of the lung – visceral and parietal pleura are continuous here○ Surfaces and features of the lungs-cardiac notch, lingula○ Pulmonary ligament – an extension from the root of the lung○ Bronchus-main, lobar, segmental – main contains cartilage○ Endothoracic fascia – weblike CT between the thoracic wall and costal parietal pleura

Heart and Middle Mediastinum○ Objectives

The pericardial reflection indicated on page 52-54. The cardiac vessels (pgs. 54-56). The features of the right atrium and ventricle and the left atrium and ventricle highlighted on pgs. 56-59.

○ Structures Middle mediastinum

Nerves:○ Left vagus – crosses the left side of the aortic arch○ Recurrent laryngeal – located inferior to the aortic arch and posterior to the ligamentum arteriosum

Blood vessels:○ Arch of aorta○ Ascending aorta○ Superior vena cava○ Inferior vena cava○ Pulmonary trunk○ Pulmonary veins

Other:○ Ligamentum arteriosum – connects pulmonary trunk to aorta

Pericardium:○ Serous pericardium – inner surface of the pericardium○ Fibrous pericardium○ Pericardial cavity○ Oblique pericardial sinus – stick fingers underneath heart from apex and push then until they are stopped

by the reflection of the pericardium○ Transverse pericardial sinus – posterior to pulmonary trunk and aorta, in front of superior vena cava?

Coronary vessels:○ Note – they are located between the visceral pericardium (epicardium) and the muscular surface of the

heart○ Left coronary artery○ Anterior interventricular branch

Circumflex branch

○ Right coronary artery Marginal branch Posterior interventricular branch Anterior right atrial branch

○ Great cardiac vein○ Middle cardiac vein○ anterior cardiac vein – only cardiac vein that doesn’t drain into the cardiac sinus

Heart:○ Note – RA surface is smooth○ Atrioventricular sulcus (coronary)○ Interventricular sulcus○ Right and left auricles○ Coronary sinus○ Pectinate muscle – horizontal ridges of muscle○ Cristae terminalis – vertical ridge of muscle that connects the pectinate muscles○ Valve of the coronary sinus○ Fossa ovalis○ Location of the SA and AV nodes○ Chordae tendineae○ Papillary muscles○ Trabeculae carnae – muscular ridges on RV and LV○ Septomarginal trabeculae – from IV septum to base of anterior papillary muscle in RV, contains part of

the conduction system○ Conus arteriosus – leads to the pulmonary valve and is smooth

Infundibulum○ Pulmonary surface – on the left side touching the lung

Heart valves:○ Aortic and pulmonary semilunar○ Atrioventricular (mitral/bicuspid)○ Atrioventricular (tricuspid)

Superior and Posterior Mediastinum○ Objectives

The highlighted structures of the superior and posterior mediastinum indicated on pages 59-63.

○ Structures Superior and Posterior Mediastinum

Nerves:○ Right and left vagus – passes posterior to the

root of the lung Both supply the esophageal plexus

○ Esophageal plexus○ Anterior and posterior vagal trunks –

continuation of vagus nerve○ Sympathetic trunk – crosses heads of ribs 2-9,

but is on sides of thoracic vertebra○ Greater splanchnic – receives contributions

from the 5-9th thoracic sympathetic ganglia Not completely formed until lower thoracic

○ Paravertebral ganglia

○ Intercostal○ Right and left phrenic ○ Left recurrent laryngeal

Vessels:○ Azygos vein – drains into the superior vena cava○ Hemiazygos vein – the lower one crossing at T8○ Accessory hemiazygos vein – the higher one crossing at T9○ Descending aorta○ Posterior intercostal arteries – the right side ones are tributaries of the azygos vein○ Posterior intercostal veins○ Bronchial arteries – come directly from the aorta○ Right and left brachiocephalic veins○ Superior vena cava○ Branches of Arch of Aorta

Brachiocephalic artery Left common carotid artery Left subclavian artery

Other:○ Esophagus○ Thoracic duct – drains into left internal jugular vein

On left side in between azygos and descending aorta Crosses anterior to azygos structures

○ Bifurcation of the trachea○ Carina

Anatomy Histology Lab – Test 1

Back○ Objectives

Identify the two layers of the skin and the morphology of their component parts. Be able to identify the hypodermis and its function and relationship to the skin

Identify the various types of skin and their location on the body. Relate their morphology to function. Be able to discuss the structural components that hold the skin together as a functioning unit

Relate the morphology of the skin to its function and developmental formation Identify the various appendages of the skin (hair, glands and nails) and relate their function to their morphology and formation Identify the structures responsible for skin color Identify the various receptors found in the skin and relate their physiological function Identify the morphological structures affected by the wound healing process and by the various types of burns Relate solar elastosis, psoriasis, phemphigus, tanning and carcinoma to the structure and function of the skin

○ Notes The whole thickness of the skin tends to be thicker on the dorsal side of the body

○ Thick Skin Regions

Epidermis○ Stratified squamous keratinized epithelium○ Has a basement membrane○ Contains keratinocytes, melanocytes, Langerhans (not identifiable) and Merkel (not identifiable)○ Layers

Stratum Corneum – heavily keratinized layer with no nuclei○ Squames – keratinocyte cells in this layer○ Lots of squames because it is thick skin

Stratum Lucidum – clear layer where cells are beginning to flatten (variable appearance) Stratum Granulosum – irregular cuboidal spindle shaped cells○ Characteristic – dark staining keratohyalin granules in cytoplasm○ Nuclei present only in innermost layers

Stratum Spinosum – fuzzy gaps between cells due to presence of desmosomes Stratum Basale – immediately above basement membrane○ Where proliferation of new keratinocytes occurs

Malpighian layer – the last two layers Dermis○ Dense irregular CT

Layers○ Papillary Layer – thin layer that interdigitates with epidermis

Thin, lighter staining area closest to the epithelium Contains subpapillary plexi (blood)

○ Reticular Layer – thicker layer deep to papillary Contains bundles of large diameter collagenous fibers, blood vessels and nerves Elastic fibers also seen only if elastic stain is used Contains cutaneous plexi (blood)

Hypodermis – not part of skin, loose CT with adipose○ Dermal Papillae – CT ‘projections’ of dermis into epithelium

If Thin Skin → Rete pegs – downward projections of epithelium into the dermis, between dermal papillae○ The two of these things combined helps prevent dermis from shearing

If Thick Skin → Epidermal ridges – things between dermal papillae the give fingerprints○ Thin Skin (hairy)

Characteristic – much thinner stratum spinosum and stratum corneum

Note that melanocytes don’t look dark, they just produce the melanin and it becomes dark outside the cells via tyrosinase

○ Sensory Receptors Meissner’s Corpuscles

Encapsulated nerve endings, light touch, found in dermis Oval or pear-shaped, found in dermal papillae Whole thing is perpendicular to surface, but CT nuclei are parallel Found mainly in thick skin

Pacinian Corpuscles Encapsulated (in CT) nerve ending, pressure, found in reticular layer of dermis and hypodermis Circular and look like a cross section of an onion

Merkel Cell – Electron Micrograph Mechanoreceptor in epidermis, light touch Up against the terminal end of an axon You can see dark granules containing neurotransmitters coming from the Merkel cell

○ Appendages Glands

Secretory regions are light staining and the duct regions are dark staining Eccrine Sweat Glands – small, highly coiled tube○ Usually smaller lumen than apocrine○ Simple cuboidal epithelium○ Found at dermis/hypodermis junction○ Merocrine secretion

Apocrine Sweat Glands – larger lumen compared to eccrine, highly coiled tube○ Cells usually stain lighter pink○ Simple cuboidal or columnar epithelium○ Found at dermis/hypodermis junction○ Empty into upper portion of hair follicles○ Merocrine secretion

Sebaceous Glands – large, alveolar (grape-like) sac in dermis emptying into hair follicle○ Can see holocrine secretion in action (seeing cells die, lose their nucleus and leave)

Hair Bulb – contains melanocytes, contains a central dermal papilla continuous with dermis CT Sheath – CT of surrounding dermis and basement membrane of epidermis○ Basement membrane of dermis is just outside external root sheath and is glassy

External Root Sheath – continuous with stratum basale and stratum spinosum Internal Root Sheath – goes half way up Hair Shaft – ○ Medulla – central part at base○ Cortex – makes up most of hair shaft, keratinocytes filled with hard keratin○ Cuticle of hair shaft – outside of hair shaft

Errector Pili Muscles – smooth muscle cells diagonally attached to hair follicles○ Anchored to papillary layer of dermis

Nails Nail Plate – contains keratinocytes with hard keratin Nail Bed – immediately beneath nail plate, continuous with stratum basale and stratum spinosum Nail Root – ? Nail matrix – ?contains undifferentiated epithelial cells Nail Fold – on sides Eponychium – epithelium overhanging the proximal side of the nail plate

Hyponychium – underneath the free edge of the nail Blood○ Objectives

Be able to distinguish cells in the white series from those in the red series Be able to identify all classes of cells circulating in the blood Be able to identify the compartments in the bone marrow Be able to identify major cell types in the bone marrow that can be distinguished at the light microscopic level In the red developmental series, be able to distinguish each stage of development

○ Four classes of things in peripheral blood – erythrocytes, granular leukocytes/granulocytes, agranular leukocytes, platelets

○ Note – basophils are hardest to find because there are so few○ Blood is a modified connective tissue and originates from the mesoderm of developing embryo○ Blood Smear

Neutrophils – no visible granules, multilobed nucleus (2-5 with fine strands connecting them) Women may have an extra small lobe for the X chromosome Most numerous Immature neutrophils are called band cells and have a horseshoe shaped nucleus○ If increased then this indicates infection

Eosinophils - characterized by – large red granules in cytoplasm Two lobed nucleus, but this is often difficult to see

Basophils - characterized by S-shaped or bi-lobed nucleus and dark blue granules Lymphocytes – most numerous agranulocyte

characterized by – being almost all nucleus○ very thin rim of bluish cytoplasm

Monocytes - characterized by kidney bean shaped nucleus, with a nucleolus in each lobe Cytoplasm can have a grayish blue tint

Platelets – basically little blue dots○ Bone Marrow

Stem cells that make both red and white blood cells are not visible Criteria for evaluating cell type and stage of maturation

Size of the cell and nucleus – usually this ↓ as it matures Appearance of chromatin – immature cells have dilcate fine-meshed chromatin, mature cells have

coarser, condensed darker chromatin Presence of absence of nucleoli – pale blue circles in chromatin of immature cells Cytoplasmic basophilia – very immature cells have pale blue cytoplasm due to only a few scattered

ribosomes (esp red series) White adipocytes – can be seen Hematopoietic cord – concentrations of cells in bone marrow Megakaryocytes - characterized by large, irregular, multi-lobed nuclei and abundant cytoplasm

At EM Level - demarcation channels can be seen as platelets are produced Sinusoidal capillaries – have thin endothelial wall Erythropoiesis

Proerythroblast ○ finely meshed chromatin in nucleus○ generally two prominent nucleoli○ cytoplasm is a little blue due to some ribosomes

Basophilic erythroblast ○ Nucleus is very basophilic due to lots of RNA○ Cytoplasm is also blue due to free ribosomes

Polychromatic erythroblast ○ Nucleus is still basophilic due to RNA

○ Cytoplasm is lilac because it is filled with ribosomes and hemoglobin (which stains red) Orthochromatic erythroblast○ Nucleus more basophilic and pyknotic, possibly towards edge of cell○ Cytoplasm is red because of all the hemoglobin

Reticulocytes – immature RBCs found in peripheral blood which indicate rate of erythrocyte production Nucleus is gone, but some ribosomes still there and are stained blue

Granulopoeisis Myeloblast – large cell○ Nucleus - pale staining nucleus, 2-5 nucleoli○ Cytoplasm – a light blue (few ribosomes)

Promyelocyte – similar to myeloblast except it has a few granules○ Smaller?

Myelocyte – differentiates into all three granulocytes○ Characterized by slight indentation in nuclei AND accumulation of cell specific granules

Metamyelocyte – kidney bean nuclei and cell specific granules○ Note – neutrophil granules are very fine and a little red when compared to others

Neutrophilic Band Cell – an extra stage in neutrophil development○ Has horseshoe shaped nucleus○ If ↑ then indicates infection

Mature Cell – Respiratory System○ Objectives

Be able to recognize the anatomical components of the respiratory system at the microscopic level Be able to recognize the specific components and distinguishing features of respiratory and olfactory epithelia Recognize and be able to distinguish the epithelia and submucosa found in the nasal cavity, pharynx, larynx,

trachea, bronchi, bronchioles, and alveolar airways. Explain the structure and function relationship of each of the above regions

Be able to recognize the structure and location of ciliated cells, mucus-producing cells, alveolar macrophages, type I and type II pneumocytes

Be able to recognize and discuss the functional significance of the bony and cartilaginous structural components of the respiratory system

Be able to recognize the muscular components of the airways Be able to recognize each type of airway found within the lungs

○ Nasal Cavity Identify nasal mucosa in cross section of fetal skull Identify nasal septum which contains hyaline cartilage Respiratory Epithelia (Mucosa) – in portion near oral cavity

Outer Layer○ pseudostratified, ciliated, columnar epithelium with goblet cells○ 2-3 layers of nuclei○ Goblet cells are wider and lighter staining

Lamina Propria – contains lots of glands and blood vessels Olfactory Epithelia

Outer Layer - Modified PCCE that is much thicker with 5-8 layers of nuclei Lamina Propria – contains large nerve bundles, blood vessels and○ Bowman’s Glands – secrete serous substance

Kinda hard to identify, but will have a duct going through the epithelium to surface ○ Nerve bundles are either unmyelinated (olfactory nerves) or myelinated (trigeminal sensory)

○ Epiglottis Often seen in longitudinal section with lots of dark elastic staining in the middle

Lingual Surface - stratified squamous mucosal epithelium (because has more trauma) Laryngeal Surface – PCCE Contains many blood vessels and sero-mucous glands in underlying CT

○ Larynx Epithelium

Superior to vocal fold – mainly PCCE, but could have undergone squamous metaplasia in some individuals Vocal Fold - stratified squamous mucosal epithelium Inferior to Vocal fold – PCCE

Vocal Ligament – contains elastic tissue (will be very light blue without elastic stain) Thyroarytenoid muscle – medial to thyroid cartilage Vocalis Muscle – closest to vocal ligament Thyroid cartilage – more lateral and lower Cricoid cartilage – more medial and higher Cartilages are long ovals in cross section

○ Trachea Outer Layer - PCCE Lamina Propria – lots of small BVs here

Contains lots of lymphocytes and plasma cells which are much darker staining in blobs of cells Submucosa – separated from lamina propria by a thin layer of elastic lamina (find this)

Thicker CT wth large diameter BVs and some mucous and seromucous glands Note – seromucous glands will have ducts

Hyaline cartilage ring – dense CT Note that trachealis muscle (smooth muscle) is on portion of trachea next to esophagus Adventitia – outer CT layer with lots of BVs and nerves

Much lighter staining○ Bronchus

Very similar to trachea Primary Bronchi – have c-shaped cartilage rings, but smaller diameter Secondary and Tertiary Bronchi – have irregular cartilage plates Outer Layer – PCCE Lamina Propria – very thin Submucosa Muscularis completely encircles the bronchus internal to the cartilage plates

○ Lung and Bronchioles Low Magnification

Alveoli have lacy appearance○ Note – alveolar ducts are just junctions for many alveoli

Air passages with cartilage in walls are bronchi Air passages without cartilage in walls are bronchioles Blood vessels will often have RBCs in them Pulmonary arteries – travel with bronchi or bronchioles Pulmonary veins – found alone in lacy areolar network Respiratory Bronchioles – thinner walled than other bronchioles○ have alveoli connected to them but are thicker walled and more tubular

High Magnification Bronchiole - simple ciliated columnar, but lamina propria not well defined○ Has prominent muscularis○ cartilage and glands are not present○ Subtypes

Primary Bronchioles – simple columnar ciliated epithelium Terminal Bronchioles – simple columnar partially ciliated epithelium

○ Do not have alveoli opening into them Respiratory Bronchioles – simple cuboidal epithelium○ Have alveoli opening into them○ Smooth muscle may still be visible

Alveoli○ Alveolar duct → many alveolar sacs → atrium → many alveoli○ Cells lining alveoli

Type I Pneumocytes - flat and elongated, makes blood gas barrier Type II Pneumocytes - large round nuclei and clear cytoplasm○ Often bulge into luminal space

Alveolar macrophages – large cells Interalveolar Septa – walls of alveoli are very thin and contain thin-walled capillaries Pulmonary Arteries – usually travel with brochi and bronchioles○ Smooth muscle in tunica media○ Inner and outer elastic bands

Pulmonary Veins – located by themselves○ Very thin tunica media○ Absence of elastic bands

Circulatory System○ Objectives

Compare and contrast the three types of muscle tissue and indicate which are components of the circulatory system

Locate and identify the three histological layers of the heart and the component structures of the heart Integrate the structure of the cardiac skeleton with its major functions Describe and locate the cells involved in heart impulse conduction Differentiate the major levels of the arterial and venous components of the vascular beds on the basis of their

unique structural features. Be able to identify each type. Compare and contrast the specific types of capillaries that can be identified at the LM level Compare and contrast the structure of lymphatic vessels to those of the cardiovascular system

○ Muscle Know the different muscle types

○ Heart Layers of heart wall

Endocardium – endothelium (often just one layer) and supporting CT (contains BVs and conduction system)

Myocardium – sheets of myocytes running in a spiral form○ Can see trabeculae carnae on luminal border, can see papillary muscles

Epicardium ○ Epicardial CT layer – adjacent to myocardium containing BVs, nerves and fat○ Visceral Layer – simple squamous mesothelium is visceral layer of serous pericardium

Cardiac Skeleton Composed of CT that appears to have lacunae and chondrocytes but doesn’t and is called chondroid Found between atria and skeleton Annulus Fibrosus – CT located at the base of the valve leaflets○ Valve cusps consist of collagen bundles of CT covered in epithelium and attach to annulous fibrosus that

surrounds valve opening They could have stained CT green and muscle pink Purkinje Fibers – lighter staining cell mixed in with myocytes near epithelium○ Lighter staining because of less myofibrils

○ Blood Vessels

Large Large Elastic Arteries○ Can see tunica intima, tunica media, tunica adventitia○ Can see lots of elastic fibers if stained with the right stain○ Can see elastic and collagenous fibers and vaso vasorum of tunica adventitia○ External elastic membrane is outermost elastic lamina

Large Veins○ Tunica media is very thin, tunica adventitia is the thickest layer○ Tunica adventitia made of irregular bundles longitudinally oriented of smooth muscle (usually SM is

oriented circularly)○ Can see vaso vasorum penetrating deeply

Medium Muscular Artery○ Can see tunica intima, tunica media, tunica adventitia○ Scalloped internal elastic lamina and prominent

Has fenestra to let things pass through○ Find endothelium, and subendothelial CT of tunica intima○ Find smooth muscle fibers in tunica media (a bunch of layers)○ Find external elastic lamina, collagenous fibers, elastic fibers, vasa vasorum in tunica adventitia

Medium Vein○ Can see tunica intima, tunica media, tunica adventitia○ Endothelium of tunica intima○ Elastic and Muscle fibers of tunica media○ Elastic and collagenous fibers of tunica adventitia

Small Arterioles – 1-5 layers of SMC Venule – irregular lumen, no internal elastic lamina, no circularly oriented SMCs, thicker tunica adventitia

Capillaries – easiest way to find them is to look for a single RBC surrounded by a single endothelial cell You cannot distinguish the type of capillary at LM level unless you induce it by noting which tissue it is in

Sinusoids – occur in liver and spleen Large, irregularly shaped lumen Thin walls containing fenestrated endothelial cells and a _discontinuous basal lamina

Note – arteries and veins will come in pairs, the arteries are easier to identify and the veins are larger Lymphatic System○ Objectives

Be able to identify active from inactive lymphatic nodules Be able to follow normal blood and lymph flow through a lymph node Be able to follow blood flow through the spleen Be able to distinguish the red pulp from the white pulp and known their functions in the spleen Be able to differentiate between the cortex and medulla and know their different functions in encapsulated

structures Be able to identify each region in a Peyer’s patch Know the location and function of the different kinds of cells that make up the lymphatic system Be able to identify in which regions B and T cells function in the lymphatic system Be able to identify macrophages in the various tissues where they are found Be able to identify plasma cells and know their function Be able to distinguish a young from post-pubertal thymus Be able to identify all regions of the thymus and be able to follow a white blood cell through the thymus

○ Note – thymus does not normally contain plasma cells○ Note – diffuse lymphoid tissue and solitary lymphoid nodules are often found in the lamina propria

○ Aggregated nodules found in Peyer’s patches of ileum and appendix○ Partially encapsulated lymphoid tissue found in tonsils and adenoids○ Mononuclear Phagocyte System

von Kupffer cells – blue staining phagosomes along the liver sinusoids○ Diffuse Lymphoid Tissue

Trachea Diffuse lymphatic tissue – made of scattered lymphocytes, macrophages and plasma cells) in lamina

propria and submucosa of trachea.○ Found in dark blue patches

Lymphoid Nodules – dense patches sometimes found in submucosa Mammary Gland

IgA Plasma cells are located in the CT of the secretory lobules○ Have eccentrically located nucleus and the chromatin looks like spokes of a wheel○ Rich in ribosomes and proteins to make it dark blue○ Produce antibodies to transfer to child via milk

○ Aggregated Nodular Lymphoid Tissue Ileum

Peyer’s Patch – aggregation of lymphoid nodules in the ileum containing primary nodules and B-cells○ Found in lamina propria under luminal gastric epithelia○ Not surrounded by CT capsule○ Nice blue blobs that look like germinal centers○ Contain M Cells (move antigen into peyer’s patch) at junction of peyer’s patch and GI○ Only on one side of the GI lumen

High Endothelial Venule – where lymphocytes leave the vessel○ Are simple cuboidal instead of simple squamous○ Really tough to identify

Appendix Contains secondary nodules that are much like peyer’s patches, only they are located all the way around the

GI lumen B-cells located in top portion (away from GI lumen) - lighter staining T-lymphocyte cap – darker staining portion near GI lumen

○ Partially Encapsulated Lymphoid Tissue Tonsils – organized lymphoid tissue with 1. epithelial inpocketings, 2. partial CT encapsulation, 3. a course

internal framework of CT Crypts – deep tubes that are like invaginations, here the characteristic epithelium exists Contain primary nodules and germinal centers

Palatine Tonsil - Characterized by stratified squamous mucosal epithelium Have mucous glands - light staining with one layer of epithelium around flower structure

Pharyngeal Tonsil - Characterized by PCCE with goblet cells Have mixed seromucous glands

○ Encapsulated Lymphoid Organs Lymph Node – completely surrounded by CT, has cortex and medulla

Cortex – characterized by primary nodules (haven’t been activated yet) and secondary nodules○ Secondary nodules have germinal centers

Medulla - lighter staining center, less lymphocytes, more trabeculae○ Medullary Sinuses – light staining areas○ Medullary Cords – irregular dark staining areas

Paracortex – region where cortex and medulla meet○ Contains high endothelial venules (which have characteristic simple cuboidal endothelium

Lymph Flow – afferent lymph vessels (like an invagination) → subcapsular sinuses → intermediate trabecular sinuses → efferent lymphatic vessels → leave lymph node at hilum○ These sinuses are lighter staining and in specific locations

Trabeculae – CT dividing vertically Reticular Tissue – must be specially stained and are black○ There are fewer reticular fibers in germinal centers

Lymph Vessel Valve – unidirectional due to presence of valve○ Valve looks like a ‘V’, note direction of lymph flow

Spleen Visceral peritoneum – surrounds the CT Trabeculae – red staining structures that spread out from hilum○ Trabecular vessels – run along trabeculae and are branches of the splenic artery

White Pulp – round masses of darkly staining lymphocytes surrounding a central artery (which is red staining)○ PALS (periarterial lymphoid sheath) – white pulp immediately surrounding central artery○ Marginal Zone – portion of white pulp at periphery, sometimes ill-defined, but contains a bunch of

capillaries. Completely devoid of sinusoids Red Pulp - red staining tissue surrounding white pulp, contains lots of RBCs and lymphocytes○ Splenic sinuses – light areas possibly containing nothing, high mag, endothelial lined spaces, difficult

to see○ Splenic cords (Billroth’s cords) – macrophages live here○ Penicilli – short straight arterioles in red pulp

Thymus CT divides it into lobes, only lobulated lymphoid organ○ Each lobe contains cortex (darker staining, peripheral) and medulla (lighter staining, central)

Does not contain lymphatic nodules or lymphatic sinuses Characterized by presence of Hasall’s corpuscles Hasall’s corpuscles - red staining spheres of concentrically layered cells found in medulla Interlobar septa – CT between lobules which carry blood vessels Not in the lymphatic circulation Involuted Thyroid – looks dead, but still a functional organ