Pseudostratified Columnar Epithelium
Function: Secretes mucus which is moved with cilia
Location: Trachea and most of upper respiratory tract

Transitional Epithelium
Function: Allows expansion and recoil after stretching
Location: Urinary bladder, ureter

Two types of neuroglia in PNS
Satellite Cells
Similar to functions of astrocytes small cells that surround the neurons in the sensory, sympathetic and parasympathetic ganglia, helping to regulate the external chemical environment

Schwann Cells
Similar in function to oligodendrocytes and microglial cells, providing myelination to axons in the RNS, also have phagocytosis activity.

Myocardium – the middle layer of the heart wall
Function – stimulates heart contractions to pump blood from the ventricles and relaxes the heart to allow atria to receive blood, allowing a heartbeat

Endocardium – the thin inner layer of the heart wall
Function – lines cavities and valves to regulate blood flow. Keeps blood flowing through the heart separated from the myocardium or cardiac muscles

2. Four chambers of the heart
Right Atrium – forms the right border of the heart and receives blood from three veins
Function – receives oxygen-poor blood from the body and pumps it to the right ventricle

Left Atrium – forms most of the base of the heart
Function – receives oxygen-rich blood from lungs and pumps it to the left ventricle

Right Ventricle – forms most of the anterior surface of the heart
Function – pumps oxygen-poor blood to the lungs

Left Ventricle – forms the apex of the heart (thickest chamber)
Function – pumps oxygen-rich blood to the body

b. stratum lucidum – 2-3 layers of anucleate, dead cells; seen only in thick skin
Function – extra protection

c. stratum granulosum – 3-5 layers of keratinocytes with distinct keratohyalin granules
Function – contains cells that have granules to make keratin

d. stratum spinosum – several layers of keratinocytes all joined by desmosomes; Langerhans cells present
Function – phagocytosis

e. stratum basale – deepest, single layer of cuboidal to low columnar cells in contact with basement membrane
Function – makes brown pigment (melanin)

2. Structure of nail
Description – hard plates of keratin on the dorsal surface of each distal phalanx
Function – protects the distal phalanx, fingertip, and the surrounding soft tissues from injuries. Also serves to enhance precise delicates movements of the distal digits through counter-pressure exerted on the pulp of the finger.

b. Submucosa – consists of areolar connective tissue that binds the mucosa to the muscularis
Function – allows mucosa to move flexibly during peristalsis

c. Muscularis – thin layer of smooth muscle that forms part of a mucous membrane.
Function – peristaltic movements and segmental contractions

d. Serosa – the outer lining of organs and cavities of the abdomen, including stomach.
Function – lubrication of large intestine through secreting serous fluid.

2. Wall of the stomach with rugae
Rugae – the mucosa and submucosa of the empty stomach have large, longitudinally directed folds called rugae; flattens when the stomach fills with food.
Function – allows expansion of the stomach after the consumption of food

3. Tooth
Description – hard, resistant structure occurring on the jaws or around the mouth
Function – breaking down of food to allow food to be turned into bolus

Enamel – the hardest component of the human body

Odontoblast – tall polarized cells derived from the cranial neural crest that line the tooth’s pulp cavity

Ameloblast – contains numerous secretory granules with the proteins of the enamel matrix.