Question

The Diversity of Life

Examine the images of organisms and their descriptions in the table. Then, answer the lab review questions.

Organism

colony of cells that contain chloroplasts, organelles, and a nucleus

covered in hair- like cilia that it uses to move reproduces asexually by binary fission has a binary nucleus

eats algae, yeast, and bacteria

peptidoglycan in the cell wall

some species are pathogenic, while others are part of the human skin, respiratory tract, etc.

gram-negative

heterotrophic species found in the human gut

Properties

Lab Review

1. Classify these organisms according to their domains.

2. Compared to other domains, scientists know relatively little about bacteria, even though they are so numerous. How has the study of bacteria been limited by technology in the past? What are some promising new ways to study bacteria, and what can scientists learn from these methods?

3. Describe a few ways in which endosymbiotic theory has changed the way scientists think about the ancestral distinctions among the three domains.

Answers

GPT 3.5
Answers may vary, but here are some possible responses:

1. The first organism, a colony of cells with chloroplasts, organelles, and a nucleus, would fall under the domain Eukarya. The second organism, with cilia and binary fission, peptidoglycan in the cell wall, and gram-negative, would be classified under the domain Bacteria. The third organism, a heterotrophic species found in the human gut, would also fall under the domain Bacteria.

2. In the past, technology limitations such as the inability to culture certain bacteria in a lab setting, as well as difficulties in visualizing and understanding their cellular processes, have hindered the study of bacteria. However, new technologies such as advanced microscopy, genetic sequencing, and metagenomics are offering promising ways to study bacteria. These methods allow scientists to observe bacteria in their natural environments, sequence their genomes, and understand their mechanisms of action in greater detail.

3. The endosymbiotic theory suggests that organelles such as chloroplasts and mitochondria were once free-living bacteria that were engulfed by eukaryotic cells and formed a symbiotic relationship. This theory has blurred the ancestral distinctions among the three domains by showing that evolutionary relationships between organisms are more complex and intertwined than previously thought. It implies that genetic material can be exchanged between different domains through symbiotic relationships, leading to a more interconnected tree of life.