QUESTION: Which of the following is not composed of a single cell only?
- Hydra
- Brewer’s Yeast
- Protozoa
- Zygote
Answer:
Hydra
| Aspect |
Cellular Level |
Introduction |
Structure |
Role |
| Hydra |
Multicellular |
A small aquatic organism belonging to the phylum Cnidaria, often found in freshwater habitats. |
Hydra has a simple structure with a tubular body, tentacles with stinging cells (cnidocytes) and a central digestive cavity. |
As a multicellular organism, it exhibits various specialized cell types and tissues. |
| Brewer’s Yeast |
Unicellular |
It is a single-celled fungus. |
Yeast cell is round or oval in shape. Yeast cell have a cell wall, cytoplasm, nucleus and other organelles. |
It is commonly used in brewing and baking industry.
It plays a role in fermentation processes by converting sugars into alcohol and carbon dioxide. |
| Protozoa |
Unicellular |
Microscopic, single-celled eukaryotic organisms found in various habitats. |
Protozoa exhibit diverse structures based on their types, with some having cilia, flagella, or pseudopodia for movement and feeding. |
They are important components of microbial ecosystems and can be pathogenic or beneficial. |
| Zygote |
Single cell |
The initial cell formed by the fusion of two gametes during fertilization. |
Zygote has combination of genetic material coming from male and female gametes. It often undergoes multiple cell divisions to develop into an embryo. |
Zygote is the mark of the beginning of the development of a new multicellular organism. |
