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Question 1

Topic – D2.2.3

What would be an advantage of using embryonic stem cells over adult stem cells in the potential treatment of spinal cord injuries in humans?

A. More cell types can be obtained.

B. Possibilities of rejection are lower.

C. The risk of stem cells forming malignant tumors is lower.

D. Unlimited numbers of cells can be extracted from the umbilical cord.

▶️Answer/Explanation

Ans. A

One advantage of using embryonic stem cells over adult stem cells in the treatment of spinal cord injuries is that embryonic stem cells have a greater ability to differentiate into a wider variety of cell types. This pluripotency could potentially enable more effective regeneration and repair of damaged tissues in the spinal cord, compared to the more limited differentiation capacity of adult stem cells.

Many types of stem cells have been explored for the treatment of spinal cord injuries. Embryonic stem cells possess pluripotency, allowing them to form any cell type in the body, including nerve cells. Induced pluripotent stem cells, reprogrammed from adult cells, share a common potential.

Question 2

Topic – A2.2.4

Which feature shared by both types of cells – aseptate fungal hyphae and striated muscle cell makes them atypical?

A. Both have cell walls.

B. Both have several nuclei.

C. Both lack membrane-bound organelles.

D. Both are divided into compartments.

▶️Answer/Explanation

Ans. B

Atypical cells are cells that are not normal but are not necessarily cancerous: 

Causes

Atypical cells can be caused by a number of factors, including inflammation, infection, and aging. 

Treatment

Atypical cells can change back to normal cells if the underlying cause is treated. This can happen naturally or through treatment. 

Follow-up

If your doctor identifies atypical cells, you should have close follow-up to monitor the cells and make sure they don’t become cancerous. 

Examples

Atypical cells can occur in the breast, urine, or blood: 

Atypical hyperplasia: A non-cancerous condition that occurs when breast cells increase in number and develop an unusual shape. 

 Atypical cells in urine: Atypical cells in urine can be a sign of high or low grade papillary urothelial carcinoma. 

Atypical circulating tumor cells: These cells can be found in the blood of cancer patients and can present as single cells, clusters of cells, or giant cells. 

 The feature shared by both aseptate fungal hyphae and striated muscle cells that makes them atypical is the presence of multiple nuclei within a single cell. In aseptate fungal hyphae, this occurs because the cell walls (septa) are absent, allowing cytoplasm and nuclei to flow freely along the length of the hyphae. In striated muscle cells, multinucleation occurs due to the fusion of multiple precursor cells during development, resulting in long, multinucleated fibers. This multinucleation is unusual because most cells contain only one nucleus.

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