How Body Responds to Injury

Question 1

What is an abscess?

Answer 1

when inflammation causes necrosis which forms a cavity containing lots of neutrophils and dead tissue

Question 2

If you find .a lymphocyte in a blood smear what does it mean?

Answer 2

likely to be chronic inflammation if theres an accumulation

Question 3

Characteristics of the Eosinophil

Answer 3

• Is another type of white cell
• So called because the cytoplasm contains granules which take up the pink stain avidly
• Associated with allergic reactions such as asthma and parasitic infections
• Eosinophils accumulation is mediated by IgE produced by plasma cells
• Eosinophils produce inflammatory mediators; the more eosinophils present in the tissue, the worse are the symptoms suffered by the patient

Question 4

What is a polyp and how do nasal polyps form?

Answer 4

Polyp – benign growth with a stem that grows into a cavity

Swelling of mucosa caused by allergic reaction.

Question 5

Characteristics of a monocyte

Answer 5

•Has a single reniform

(kidney – shaped) nucleus

and lots of cytoplasm

• Functions as a phagocyte, but does not do this in the circulation but in the tissues where its known as macrophage or histiocyte
• A macrophage is a cell of chronic inflammation

Question 6

What is it called when macrophages join to form a single cell?

describe it

Answer 6

Horse-Shoe Shaped Giant Cell

•When macrophages join up together to create a single cell with multiple nuclei this is termed a giant-cell.

Question 7

List the causes of poor wound healing:

Answer 7

1. C for poor Circulation
2. I is for Infection
3. E for excess Movement
4. FB is for Foreign Body
5. V for vitamin C deficiency (collagen synthesis)
6. DM is for Diabetes Mellitus

Question 8

What is the difference between primary and secondary intention?

Answer 8

Primary is when you bring two ends of the skin of the wound together to heal

Secondary is when the wound is to large to suture up two ends of the skin, prone to complications

Question 9

when would skin grafts be used?

Answer 9

When the wound is beyond healing by secondary intention

Question 10

what are the four mechanisms used when the cell attempts to adapt to a hostile environment?

Answer 10

• metaplasia
• hypertrophy
• atrophy
• hyperplasia

If all fails then cell death

Question 11

Metaplasia definition and when it occurs

Answer 11

• Occurs when one type of mature cell differentiates to another form of mature cell
• Occurs as a form of adaptation in face of a hostile environment
• Metaplastic epithelium is associated with high risk of developing cancer

Question 12

Examples of metaplasia

Answer 12

• Oesophagus: Squamous epithelium changes to columnar epithelium → Barrett’s oesophagus due to gastric contents reflux
• Bronchus: Pseudostratified ciliated columnar epithelium changes to squamous epithelium due to smoking
• Cervix: Columnar endocervical mucosa infected by HPV changes into squamous epithelium

Question 13

Define hypertrophy, atrophy

Answer 13

Hypertrophy

• Can be physiological or pathological
• Hypertrophy is an increase in cell size resulting increase in the size of the organ

Atrophy

•Atrophy occurs when the cell decrease in size resulting in shrinkage of the organ

e.g. post menopausal atrophy of the uterus due to lack of oestrogen stimulation

Question 14

define hyperplasia

Answer 14

• Hyperplasia occurs when there is increase in number of cells which results in increase in the size of the organ
• Common example is the increase in cells of the prostate in older men resulting in condition termed benign prostatic hyperplasia (BPH)
• This causes problems with urination
• Can result in urine retention