ZOOL 441 HISTOLOGY NAME:_____________________________________
EXAM 2, 10 November 1994

I. Define and/or discuss the following terms. For histological structures, include
statements regarding the histology, location and function of the structure. (4 pts. each,
20 pts. total).

1. Islets of Langerhans



2. Meissner's Corpuscles



3. Ameloblasts



4. Ependymal Cells



5. Intercalated Discs




II. Fill-in the blank. (2 pts. per blank, 40 pts. total).

1.________________________ Smallest contractile unit of skeletal muscle

2.________________________ Epidermal layer composed of "prickle cells"


3.________________________ Muscles of tongue allowing movement of
tongue tip

4.________________________ Germinative zone of gastric glands

5.________________________ Portion of digestive tract functioning mainly to
reabsorb water

6.________________________ Most common neuron type within the body

7.________________________ Name 2 adaptations that increase the surface

8.________________________ area of the small intestine

9.________________________ Layer of dermis providing nutrients and oxygen
to epidermis

10._______________________ Region of sarcomere containing
both actin and myosin myofilaments

11._______________________ Collection of nerve cell bodies outside CNS

12._______________________ Corpuscle type located in dermis and
subcutaneous tissue that is responsive to pressure

13._______________________ Glial cell type responsible for myelination in
CNS

14._______________________ Serous glands in tongue washing tongue free
from dissolved molecules

15._______________________ Ribosome-containing structures in cell body of
nerve cell

16._______________________ All muscle fibers innervated by a single neuron
are called a ______.

17._______________________ Nerve plexus innervating muscularis mucosae

18._______________________ Name for large masses of lymph nodules
present in lamina propria of ileum

19._______________________
2 components of blood-brain barrier
20._______________________


III. Multiple Choice. Choose the best answer. (2 pts. each, 20 pts. total).

1. The portion of the synapse that receives the impulse and usually consists of a
terminal expansion of an axon is the _____.

a) presynaptic terminal, b) postsynaptic terminal, c) depolarizing junction, d) synaptic
cleft, e) gap junction

2. Which of the following tooth components is at least partially cellular in nature?

a) enamel, b) dentin, c) cementum, d) interprismatic substance, e) none of the
preceding are cellular

3. Which of the following is true of smooth muscle?

a) multinucleate, b) involuntary, c) actin and myosin are not involved in contraction,
d) cytoskeleton lacks the tonofilaments present in skeletal muscle, e) all are true

4. Which of the following salivary glands has mucous secretory units that are
commonly capped with serous demilunes?

a) Parotid, b) Sublingual, c) Brunner's, d) Submandibular, e) Cardiac

5. Nodes of Ranvier _____.

a) are present in nonmyelinated axons, b) act to increase the velocity of nervous
conduction, c) stain black with osmic acid, d) insulate nerve fibers, e) all of the
preceding

6. Kupffer cells in the sinusoids of the liver are responsible for ____.

a) production and secretion of bile, b) increasing surface area for absorption from the
blood, c) breakdown of liver glycogen stores, d) phagocytosis of material within the
blood, e) production of enzymes that emulsify fats

7. The cerebellar neuron type that functions to convey motor impulses from the cortex
which inhibit function of medullary neurons within the cerebellum is the
_____ cell.

a) Pyramidal, b) Polymorphic, c) Basket, d) Golgi, e) Purkinje

8. Placoid scales are homologous with teeth and are present in the skin of

a) cyclostomes, b) elasmobranchs, c) teleosts, d) terrestrial amphibians, e) reptiles

9. The cell type in the gastric gland secreting proteolytic enzymes is the ____ cell.

a) Parietal, b) Paneth, c) Enteroendocrine, d) Chief, e) Peyer's

10. Which of the following secretes a solution that functions to lubricate the surface of
the eye?

a) ceruminous gland, b) uropygial gland, c) meibomian gland, d) sebaceous gland, e)
lacrimal gland


IV. Essay (10 pts. each, 20 pts. total).
1. Describe the structure of the T-tubules and Sarcoplasmic Reticulum of muscle cells
and explain how this structure is related to their function.










2. Compare and contrast the skin of mammals with the skin of teleost fish. Include in
your discussion statements regarding the epidermis, dermis, skin derivatives and
skin glands. How does the skin of these organisms serve as an adaptation to the
environment that they inhabit?