QCAA Biology Alternative Sequence Cells as the basis of life

This is incorrect because prokaryotic cells lack a true nucleus. Their DNA is instead located in an unbound region of the cytoplasm called the nucleoid.

This is incorrect because prokaryotes, such as bacteria and archaea, are exclusively single-celled (unicellular) organisms.

This is incorrect because a defining characteristic of prokaryotic cells is the complete absence of membrane-bound organelles like mitochondria or chloroplasts.

While enzymes are involved in cellular processes, the folded structure itself does not provide enzymes. Instead, folding is a structural adaptation to maximize physical space.

Packaging proteins into vesicles for secretion is primarily the function of the Golgi apparatus, not the reason for the endoplasmic reticulum's folded structure.

Although the endoplasmic reticulum is continuous with the nuclear membrane, this connection is not the reason its folded structure assists in protein synthesis.

Stem cells are unspecialised, not specialised. Once a cell becomes specialised, it typically loses its high potency and ability to differentiate into other cell types.

While stem cells do divide to self-renew, they are also capable of differentiating into various specialized cell types, which is essential for tissue growth and repair.

Stem cells are undifferentiated, meaning they have not yet developed into a specific cell type. Differentiated cells are already specialized and generally cannot produce other cell types.

The primary structural component of the membrane is a lipid bilayer, not a double layer of proteins. While carbohydrates are present, they are typically attached to lipids or proteins on the extracellular surface.

While the membrane is a double layer of lipids, it contains embedded protein channels, not carbohydrate channels. Carbohydrates act mainly in cell recognition rather than as transport channels.

The cell membrane is composed of a phospholipid bilayer, not a double layer of carbohydrates. Carbohydrates are found on the outer surface, while proteins form the embedded transport channels.

Incorrect. Phagocytosis is a type of bulk transport where cells engulf large solid particles, not individual dissolved molecules like glucose.

Incorrect. While secondary active transport is used in specific areas like the intestines, glucose primarily enters most body cells passively without the direct use of ATP.

Incorrect. Glucose is a large, polar molecule and cannot easily pass through the hydrophobic lipid bilayer of the cell membrane on its own.

This value does not follow the inverse relationship between magnification and field of view. Because the magnification increased by a factor of 4, the original field of view must be divided by 4.

This value is larger than the original field of view. As magnification increases, the field of view must decrease, not increase.

This results from incorrectly multiplying the original field of view by 4 ($1800 \mu\text{m} \times 4 = 7200 \mu\text{m}$). Field of view is inversely proportional to magnification, so you must divide, not multiply.

Prokaryotic cells lack a true nucleus; their genetic material is located in an unbound region called the nucleoid. Having a nucleus is a defining characteristic of eukaryotic cells.

Both prokaryotic and eukaryotic cells contain ribosomes, which are essential for protein synthesis, so this feature does not differentiate the two cell types.

Prokaryotic cells lack membrane-bound organelles, such as mitochondria or the Golgi apparatus, which are instead a defining characteristic of eukaryotic cells.