Page 81 - Biology_Form_3

Biology for Secondary Schools

significantly shorter-than-average height. problems or spinal issues can help prevent
In proportionate dwarfism, all body parts complications later in life.
are proportionately smaller whereas in
disproportionate dwarfism, certain body Cushing’s Syndrome
parts such as limbs become much shorter Cushing’s syndrome is caused by prolonged
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than the torso as shown in Figure 3.3. Other exposure to high levels of cortisol, a
characteristics include delays in motor hormone produced by the adrenal glands.
skills, such as walking, due to shorter limbs The most common cause is the use of
or joint issues. Certain forms of dwarfism corticosteroid medications for extended
can lead to distinctive facial features, such periods. Other causes include a tumour
as a flattened nose bridge or a prominent in the pituitary gland (Cushing’s disease)
forehead, and joint problems can arise, or an adrenal gland tumour. Symptoms of
limiting mobility. Cushing’s syndrome include rapid weight
gain, particularly around the abdomen
The disorder can cause joint problems, and face (moon face), thinning skin,
especially in those with disproportionate easy bruising, high blood pressure, and
dwarfism like achondroplasia, leading to muscle weakness. Over time, Cushing’s
arthritis or limited mobility. Some forms syndrome can lead to diabetes, osteoporosis,
of dwarfism may increase the risk of spinal hypertension, and increased susceptibility
problems, heart conditions, or respiratory to infections. In severe cases, it can result
issues, depending on the specific genetic in cardiovascular disease and mental health
cause of the disorder. disorders such as depression. Prevention of
Cushing’s syndrome is primarily focused
Dwarfism caused by genetic mutations on managing steroid use. If the condition
typically cannot be prevented. However, is caused by a pituitary or adrenal tumour,
genetic counselling for parents who have surgical intervention or medication may be
a family history of dwarfism can provide required. Limiting the use of corticosteroid
important information about the likelihood drugs and opting for alternative treatment,
of the condition. The disorder caused by a when possible, can help also reduce risk.
growth hormone deficiency can be treated
with synthetic growth hormone injections
during childhood to help promote normal
growth. However, the extent of growth
possible is limited, especially in those with
disproportionate forms of dwarfism. For
individuals with specific forms of dwarfism,
such as achondroplasia, managing joint

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BIOLOGY FORM 3 FINAL EDITED 16.09.2025.indd 74
BIOLOGY FORM 3 FINAL EDITED 16.09.2025.indd 74 KAMISHNA 23/10/2025 11:52:42 KAMISHNA