USMLE PATHOMA CHAPTER 1 QUESTIONS AND ANSWERS WITH SOLUTIONS 2024

USMLE PATHOMA CHAPTER 1 QUESTIONS AND
ANSWERS WITH SOLUTIONS 2024
Hypertrophy,-,ANSWER,-Increase,in,organ,size

-
Involves,gene,activation,,protein,synthesis,,and,production,of,organelles.,i.e.,increase,in,cytoskeletal,eleme
nts

-Permanent,tissues,(<3,,skeletal,m,,and,nerve),undergo,hypertrophy,only



Hyperplasia,-,ANSWER,-Increase,in,number,of,cells

-Involves,production,of,new,cells,from,stem,cells



Atrophy,-,ANSWER,-Decrease,in,stress,leads,to,decrease,in,organ,size,and,number,of,cells

-,Decrease,in,number,of,cells,occurs,via,Apoptosis



In,Atrophy,,decrease,in,number,of,cells,occurs,via?,-,ANSWER,Apoptosis



In,Atrophy,,decrease,in,cell,size,occurs,via?,-,ANSWER,Ubiquitin-
Proteosome,degradation,of,the,cytoskeleton,and

Autophagy,of,cellular,components



Metaplasia,-,ANSWER,Change,in,stress,on,an,organ,leads,to,a,change,in,cell,type

E.g.,Barrett's,Esophagus



Metaplasia,of,Esophageal,mucosa,-,ANSWER,Caused,by,acid,reflux

Non,keratinizing,squamous,epithelium,-->,non,ciliated,,mucin,producing,columnar,cells



Mechanism,of,metaplasia,-,ANSWER,-Programming,of,stem,cells,which,produce,the,new,cell,type.

-Reversible,if,stressor,is,removed

-Can,progress,to,dysplasia,and,even,cancer,if,stress,continued

, Metaplasia-->Dysplasia-->,Cancer.,Example,and,Exception,-,ANSWER,Barrett's,Esophagus--
>,adenocarcinoma,of,the,esophagus

Apocrine,metaplasia,of,breast-->,no,increased,risk,of,cancer



Metaplasia,and,Vit,A,correlation,-,ANSWER,Vitamin,A,Deficiency,can,lead,to,metaplasia

-
Vitamin,A,is,necessary,for,differentiation,of,specialized,epithelial,surfaces,such,as,conjunctiva,covering,the,e
ye.

-Deficiency,leads,to,metaplasia,of,THIN,SQUAMOUS,lining,of,conjunctiva,--
>,STRATIFIED,KERATINIZING,SQUAMOUS,epithelium,==>,KERATOMALACIA



Myositis,Ossificans,-,ANSWER,Muscle,tissue,--
>,Bone,[during,the,healing,process].,Example,of,metaplasia,of,mesenchymal,(connective),tissue.



Dysplasia,and,example?,-,ANSWER,Disordered,cellular,growth

Reversible,with,removal,of,stress

Occurs,in,response,to,longstanding,hyperplasia,or,metaplasia.

Cervical,Intraepithelial,Neoplasia,(CIN),is,an,example.



Aplasia,and,example?,-
,ANSWER,Failure,of,cell,production,during,embyrogenesis.,Example,is,unilateral,renal,agenesis.




Hypoplasia,and,example?,-
,ANSWER,Decrease,in,cell,production,during,embryogenesis.,Example,is,streak,ovaries,in,Turner,syndrome.




Causes,of,Cellular,Injury,-,ANSWER,1.,Inflammation

2.,Nurtitional,Deficiency,or,excess

3.,Hypoxia

4.,Trauma

5.,Genetic,Mutations

6.,Infections