32
edits
Changes
→Aplasia
==Aplasia==
Aplasia also known as agenesis is the complete failure of an organ or part to form during embryogenesis.
Examples
<ul>
<li>inherited genetic defects</li>
<li>absence of limbs or amelia</li>
</ul>
==Atrophy==
==Atrophy==
Atrophy is a decrease in the size of the cells and organ, occurring after the organ has reached normal size.
Atrophy is a decrease in the size of the cells and organ, occurring after the organ has reached normal size.
* A senile change in muscles where they appear brownish rather than reddish in colour.
* A senile change in muscles where they appear brownish rather than reddish in colour.
* Due to the intracytoplasmic accumulation of [[Pigmentation and Calcification - Pathology#Lipofuscin|lipofuscin]] within the muscle fibres.
* Due to the intracytoplasmic accumulation of [[Pigmentation - Pathology#Lipofuscin|lipofuscin]] within the muscle fibres.
** The "wear and tear" pigment.
** The "wear and tear" pigment.