Why is it difficult to group bacteria into species?

• A. Bacteria have complex multicellular structures that make classification challenging.
• B. Bacteria reproduce sexually, leading to clear species distinctions.
• C. Bacteria frequently exchange genetic material through horizontal gene transfer, blurring species boundaries.
• D. Bacteria lack any genetic variation, making all individuals identical.

Answer: (C)

Verified step by step guidance

1. Understand the concept of bacterial species: Unlike animals or plants, bacterial species are not always clearly defined because bacteria reproduce asexually and can exchange genes across different groups.
2. Recognize that bacteria often engage in horizontal gene transfer (HGT), which is the movement of genetic material between organisms other than by descent from parent to offspring. This process can occur between unrelated bacteria.
3. Consider how HGT blurs species boundaries by mixing genetic traits across different bacterial populations, making it difficult to categorize bacteria into distinct species based solely on genetic similarity.
4. Note that bacteria do not have complex multicellular structures; they are typically unicellular, so structural complexity is not a major factor in classification difficulty.
5. Remember that bacterial reproduction is primarily asexual, so sexual reproduction and clear species distinctions based on it do not apply to bacteria.