CE 3 Flashcards
You are conducting a histopathological study on wound healing, which is the subject of burn treatment. You have control and experimental groups in your study. When you in samples in your control group under the light microscope, you observed normal histological structures. You detected both bleeding and infiltration areas in the subcutaneous connective tissue in the burn group. In the group treated with burns, you observed that collagen IVs were transformed into collagen I in subcutaneous tissue. In your opinion, which of the following could be the wound healing phase in the burn treatment group?
a) Hemostasis
b) Inflammation
¢) Proliferative Phase
d) Destructive phase
e) Maturation Phase
e) maturation phase
A portion of the upper esophagus, collected at autopsy, is fixed with formalin, embedded in paraffin, sectioned at 6 µm, stained with H&E, and examined by light microscopy. Identify the type of epithelium.
a) Keratinized stratified squamous
b) Nonkeratinized stratified squamous
¢) Pseudostratified columnar
d) Stratified cuboidal
e) Transitional
B) NON KERATINIZED SQUAMOUS EPITHELIUM
Which of the following fibers is MATCHED with its specifications?
a) Procollagen / is formed to fibrils in fibroblast deep folding.
b) Tropocollagen / required vitamin C for hydroxylation of collagen
c) Collagen fiber / appear white and are termed “white” fibers
d) Elastic fiber / revealed with special silver-staining procedures
e) Reticular fiber / mostly of type I collagen
c
Which of the following is composed of smooth muscle?
a) Tunica muscularis externa of stomach
b) Myocardium of heart
c) Tunica muscularis of tongue
d) Musculus biceps brachii
e) Tunica media of medium size artery
a plus e
A section of intestinal biopsy is stained with periodic acid-Schiff (PAS) staining and examined at high
magnification. Which of the following terms best describes the PAS- positive goblet cells?
a) Multicellular endocrine glands
b) Multicellular exocrine mucous glands
c) Multicellular exocrine serous glands
d) Unicellular enteroendocrine glands
e) unicellular mucus exocrine glands
e
Which of the following is TRUE location/s for Sarcomere?
a) Skeletal muscles only
b) Cardiac muscles only
c) Smooth muscles only
d) Both skeletal and cardiac muscles
e) Skeletal, cardiac, and smooth muscles
d
A section of trachea obtained at autopsy is stained with H&E and examined at high magnification. Identify the type of lining epithelium.
a) Ciliated pseudostratified columnar with goblet cells
b) Glandular epithelium
c) Keratinized stratified squamous
d) Non keratinized stratified squamous
e) Simple columnar with goblet cells
a
You are an assistant in histology lab and have just received a slide labelled “Under Autonomic Innervation”. You have been tasked with relabeling the slide as cardiac muscle. However, you can be sure of the correctness of the preparation by looking at which of the following?
a) Nuclei located on the periphery of the cell
b) Non-striated fibers, which are autonomic in nature
c) Striations in muscle with communicating junctions called intercalated disks
d) Dark staining Purkinji cells found in nervous tissue
e) Pale staining peripheric nucleus found in epithelial tissue
c
This is the impermanent type of tissue that appears in the normal development. It consists of specialized, almost gelatin-like extracellular matrix whose ground substance is frequently referred to as Wharton’s Jelly. Component cells are large, stellate fibroblasts. Their processes often appear to fuse with those of neighboring cells. If is not find in adult tissue. What is the name of this connective tissue type?
A) Reticular Tissue
B) Mucous Connective Tissue
C) Adipose Tissue
D) White Adipose Tissue
E) Brown Adipose Tissue
b
Which of the following cell adhesion proteins mediates the trans endothelial migration of leukocytes in the wound?
a) Cadherin
b) Fibronectins
c) Integrins
d) Laminins
e) Selectins
c
_________ provide strength to the epithelium by linking the actin cytoskeletons of adjacent cells and form a continuous contractile band around the cell.
a) Zonula occludens
b) Gap junctions
c) Desmosomes
d) Zonula adherens
e) Hemidesmosomes
d
You are engaged in basic research to identify novel markers for the isolation and log-term culture of hemopoietic stem cells. In addition to cord blood, hemopoietic stem cells have been isolated from which of the following fetal organs?
a) Brain
b) Gonads
c) Liver
d) Lungs
e) Pancreas
The fetal liver is the major hematopoietic organ during development
You attend a lecture about lactation and breast-feeding. Under the influence of pregnancy-associated hormones, epithelial cells of the mammary gland secrete lipids, carbohydrates, and proteins. The lipid component of breast milk is released from apical surface of the glandular epithelial cells as lipid droplets within an envelope of the plasma membrane. Which of the following terms best describes the mechanism of secretion?
a) Merocrine
b) Holocrine
c) Apocrine
d) Eccrine
e) Endocrine
Apocrine glands in the breast secrete fat droplets into breast milk
Which of the following CAN be stated about loose connective tissue?
a) It is a cellular connective tissue with abundant ground substance
b) There is less amorphous ground substance
c) The fibers are arranged in parallel array and densely packed to provide maximum strength.
d) Fibrous capsules of organs and of joints and dermis of the skin are found.
e) It allows recoil of tissue following stretching
a
A 35-year-old construction worker sustains a laceration on the palmar surface of her left hand. The wound is cleaned, sutured, and wrapped with sterile gauze. Which of the following formed elements of the blood initiates thrombosis and hemostasis in this patient’s wound?
a) Erythrocytes
b) Granulocytes
c) Lymphocytes
d) Monocytes
e) Platelets
e
The connective tissue that surrounds both individual muscle fibers and bundles of muscle fibers is essential for force transduction. At the end of the muscle, the connective tissue continues as a tendon or some other arrangement or collagen fibers that attaches the muscle usually, to bone. A rich supply of blood vessels and nerves in the connective tissue. Which of the following surrounds individual muscle fibers?
a) Sarcolemma
b) Perimysium
c) Endomysium
d) Epimysium
e) Sarcoplasmic Reticulum
c
Which of the following can be classified as “specialized connective tissue”?
a) Loose connective tissue
b) Elastic connective tissue
c) Adipose tissue
d) Dense regular connective tissue
e) Dense irregular connective tissue
c
The internal structure of microvilli contains a core of __________ that are cross linked by several actin bundling proteins.
a) Fibrin
b) Myosin I
c) Actin filaments
d) Villin
e) Espin
c
What type of epithelium lines the urinary bladder and is capable of distention?
a) Stratified columnar epithelium
b) Stratified squamous epithelium
c) Stratified cuboidal epithelium
d) Transitional epithelium
e) Pseudostratified columnar epithelium
d
In the excitation-contraction of smooth muscle, calcium binds to ___________ just after influx into the cytoplasm.
a) Tropomyosin
b) Myosin light chain
c) Troponin
d) Calmodulin
e) Protein kinase A
d
What is the released one from the terminal cisternae that combine with troponin and removes the blocking action tropomyosin, resulting in formation of cross-bridges?
a) Myosin
b) Calmodulin
c) Ca+2
d) Troponin
e) Acetylcholine
c
Which of the following does NOT effect on resting membrane potential?
a) K ions
b) Na ions
c) K-Na leaking channels
d) Proteins
e) Na-K ATPase
d
Which of the following ion flux is responsible for depolarization the skeletal muscle cell membrane?
a) sodium
b) chloride
c) potassium
d) phosphate
e) calcium
a
The term that means a continued mild or partial contraction of a muscle that keeps it healthy and ready to respond is muscle
a) tone
b) summation
c) tetanus
d) stimulation
e) twitch
a
In skeletal muscles, which of the following is a Ca+2 sensor?
a) Actin
b) Myosin
c) Troponin
d) Tropomyosin
e) Titin
c
A 56-year-old man sees a neurologist because of weakness in his legs that improves over the course of the day or with exercise. Extracellular electrical recordings from a single skeletal muscle fiber reveal normal miniature end-plate potentials. Low-frequency electrical stimulations of motor neurons, however, elicits an abnormally small depolarization. The amplitude of the depolarization is increased after exercise. A preliminary diagnosis is confirmed by the presence of which of the following?
a) Acetylcholine receptor problem
b) The voltage sensitive Ca++ channel problem
c) Mutation in the gene that codes for the ne receptor
d) Relatively few vesicles in the presynaptic terminal
e) Residual acetylcholine in the neuromuscular junction
b
Which of the following statements about acetylcholinesterase is correct?
a) Produces acetylcholine
b) Is the acetylcholine receptor in muscle tissue
c) Is responsible for smooth but not skeletal muscle contraction
d) Degrades the neurotransmitter which is found in the neuromuscular junction
e) Exist in nucleus
d
Smooth muscle contraction is terminated by which of the following?
a) Dephosphorylation of myosin kinase
b) Dephosphorylation of myosin light chain
c) Efflux of Ca++ ions across the plasma membrane
d) Inhibition of myosin phosphatase
e) Uptake of Ca++ ions into the sarcoplasmic reticulum
b
Excitation—contraction coupling in skeletal muscle involves all of the following events, EXCEPT one (find the correct answer)
a) ATP hydrolysis
b) Increased Na+ conductance of sarcolemma
c) Conformational change in dihydropyridine receptor
d) Binding of Ca++ to calmodulin
e) Depolarization of the transverse tubule (T tubule) membrane
d
Which of the following is NOT one of the sliding theory elements?
a) Actin
b) Tropomyosin
c) ATP
d) Calcium
e) Nucleus
e
The functional unit of striated muscle fiber is called?
a) Myofilament
b) Triad
c) Calcium-calmodulin complex
d) Sarcomere
e) Sarcoplasmic reticulum
d
The nervous system may activate more motor units to make muscle contraction more powerful. This process is called?
a) Summation
b) Tetanus
c) Recruitment
d) Twitch
e) Fatigue
c