General biology – Which of the following would not contain DNA?

Introduction:
Deoxyribonucleic acid (DNA) is the hereditary material in almost all living organisms and many viruses (some viruses use RNA). Recognizing which entities possess DNA helps delineate the boundary between living systems and inanimate matter in biological contexts.

Given Data / Assumptions:

• Cells (prokaryotic and eukaryotic) contain DNA.
• Fungi (yeast, molds) are eukaryotes with chromosomal DNA.
• Inanimate minerals or manufactured crystalline solids do not contain DNA unless contaminated.

Concept / Approach:
All cellular life, including bacteria, yeast, molds, plants, and animals, encodes genetic information in DNA. By contrast, glass crystals are nonliving, inorganic materials composed primarily of silicon dioxide networks without cellular structures or nucleic acids. Therefore, among the listed choices, glass crystals are the only item that inherently lacks DNA.

Step-by-Step Solution:

Verification / Alternative check:
Microscopy and biochemical assays detect DNA in cells by staining (e.g., DAPI) or extraction methods; such approaches yield no DNA from clean, uncontaminated glass due to its nonbiological composition.

Why Other Options Are Wrong:

• Yeast/mold: eukaryotic fungi with nuclear DNA.
• Bacteria: prokaryotes with circular chromosomes and often plasmids.
• Plant seeds: contain diploid plant embryos with DNA in nuclei, mitochondria, and plastids.

Common Pitfalls:
Assuming that acellular materials used in labs (e.g., agarose, glass) might contain DNA; they do not unless contaminated by biological samples.

Final Answer:
Glass crystals (inert nonliving material)