Misc

Question 1

Proinsulin is cleaved into insulin & ….. In the ….

Answer 1

C-peptide

Golgi

Question 2

I cell disease is

Answer 2

A disease in which enzymes are sent to the wrong destination due to defect in Golgi apparatus machinery

Question 3

chediak higashi syndrome

Answer 3

defect in the ability of the microtubules to polymerize in leukocytes, leading to delay in the fusion of phagosomes with lysosomes, & preventing phagocytosis of bacteria

Question 4

Define:

1. Titin
2. Desmin
3. Alpha actin
4. Myomesin
5. Nebulin

Answer 4

1. Keeps the myosin filaments centered in the sarcomere
2. Holds myofibrils in place, giving the classic striated appearance
3. Binds actin filaments to Z line
4. Binds myosin filaments to M line
5. Regulates the assembly of actin filaments

Question 5

Calsequestrin is ……….

Answer 5

a calcium-binding protein of the sarcoplasmic reticulum

Question 6

Meckle’s diverticulum is …..

Answer 6

outpouching of the ileum and is the remnant of yolk sac stalk (vitalline duct)
* In about 20% of adults

Question 7

The vitelline arteries later form …..

Answer 7

superior & inferior mesenteric arteries, and the celiac artery

Question 8

The allantois is responsible for the formation of ……

Answer 8

the umbilical vessels (two arteries one vein)

Question 9

The intraembryonic allantois persists as ……

Answer 9

the urachus (connects the bladder to the umbilicus)
* After birth, it is called median umbilical ligament

Question 10

Falciform ligament is …….

Answer 10

the stretched ventral mesentery between the liver & the ventral body wall

• The free margin carries the umbilical vein
• After birth, it becomes ligamentum teres

Question 11

The free margin of the lesser omentum carries …..

Answer 11

the hepatic artery, portal vein, and the bile duct

Question 12

Mandibulofacial dysostosis is

Answer 12

autosomal dominant defect
abnormal development of the first pharyngeal arch
* There is bony defects of the malar bone & mandible, defect in palate & ears, and defects in lower eyelid

Question 13

Fragile X syndrome is …….

Answer 13

a breakage of fragile site on the X chromosome

• Also called Martin belle syndrome
• Causes long face, low muscle tone, prominent ears & mental retardation

Question 14

Cri du chat syndrome is caused by ……

Answer 14

deletion of the short arm of chromosome 5

Question 15

What are the organisms that can cross the placenta?

Answer 15

ToRCHeS

1. Toxoplasma gondii
2. Rubella
3. CMV
4. Herpes simplex virus
5. Syphilis

Question 16

Psoriasis is ….

Answer 16

increase number of proliferations in the cells of stratum spinosum & basale

Question 17

Hair & cutaneous glands are located in the ……

Answer 17

hypodermis

Question 18

What is the difference between albinism & vitiligo?

Answer 18

• Vitiligo: destruction of melanocytes due to autoimmunity

* Albinism: Melanocytes inability in producing melanin, due to decrease tyrosine uptake, or decrease tyrosinase activity

Question 19

Pemphigus is the result of …..

Answer 19

antibodies against the TLG in desmosomal junctions

* Only the desmosome of the skin is affected

Question 20

Fordyces spots are

Answer 20

ectopic sebaceous glands on the buccal mucosa or the vermilion border

Question 21

Arrector pili are attached to …..

Answer 21

the hair shaft at one end, and the papillary dermis on the other

Question 22

Hair is composed of ……

Nails are composed of ……

Answer 22

• Keratinized dead epithelium

* modified stratum corneum with hard keratin. They are originated at the stratum basale (nail matrix)

Question 23

What is the characteristic of collagen fibers?

Answer 23

cross banding, due to overlapping of the parallel end to end fibers
* Same for the reticular fibers (since it is made of collagen)

Question 24

Ehler danlos disease is …..

Answer 24

the result of defect in Type III colagen (due to decrease hydroxylation, or defect in procolagen peptidase activity)
* Causes increased elasticity of skin, articular mobility, aortic ruptures

Question 25

Elastic fibers are the same as collagen, except .....

Answer 25

lacks the striation of collagen, thinner, and have yellow appearance * Note that: desmosine & isodesmosine are responsible for the elasticity of these fibers

Question 26

Fibronectin & laminin are ......

Answer 26

adhesive proteins | * Synthesized by fibroblasts, monocytes & endothelial cells

Question 27

B12 deficiency causes ......

Answer 27

megaloblastic anemia with hyper segmented neutrophile

Question 28

Carbonic anhydrase catalyzes the conversion of .........

Answer 28

CO2 & H2O into bicarbonate & protons | * In the stomach, protons are pumped into the lumen where they bind with Cl- to form HCl

Question 29

The gall bladder is made up of three layers, which are......

Answer 29

1. Mucosa: columnar cells, no muscularis mucosa 2. Muscularis externa: smooth muscles controlled by CCK 3. Serosa * Same layers for the cystic duct * Cystic duct joins the gall bladder to the common hepatic duct. The latter joins Wirsung duct (pancreas) to form the Ampula of Vater

Question 30

The first part of the duodenum (horizontal part) is ...... peritoneal

Answer 30

intra (in the lesser omentum) | * The rest are retro

Question 31

The portal triad includes ......

Answer 31

portal vein, hepatic artery & common bile duct | * The portal triad is within the hepatoduodenal ligament, which is the right part of lesser omentum

Question 32

The portal vein drains ....... | It is formed by .......

Answer 32

the spleen & GIT * It is formed behind the head of the pancreas (retroperitoneally) from joining of superior, inferior mesenteric & splenic vein

Question 33

The spleen is ..... in origin, however it shares the same blood supply as the foregut (celiac)

Answer 33

Mesoderm

Question 34

In liver cirrhosis, blood pressure in the portal vein will increase, causing the blood to redirect through .....

Answer 34

the esophageal branch of the left gastric vein * This causes varicoses in the esophagus. Could be a sign of advanced liver disease * Also called portacaval anastomosis

Question 35

Foregut lymph drains to .....

Answer 35

celiac lymph nodes, which ultimately drain into the thoracic duct

Question 36

The esophagus passes the diaphragm at the level of ....., through ......

Answer 36

T10 in esophageal hiatus (which also transmits the Vagus)

Question 37

Ligament of Treitz function is ......

Answer 37

suspension of the small intestine (at duodenal jeujenal junction) to the diaphragm

Question 38

The jeujenoilium is suspended from the posterior body wall by ....

Answer 38

the mesentery proper

Question 39

The transverse colon is suspended by .....

Answer 39

the transverse mesocolon | * Derivative of dorsal mesentery

Question 40

Only the ....... third of the rectum is covered by peritonium (anteriorly & laterally)

Answer 40

superior one third