Paramecium bursaria is a species of ciliate found in marine and brackish water. Algae zoochlorella live a endosymbiotic association with paramecium bursaria. Zoochlorella lives inside the bursaria in it's cytoplasm and provide food to it. while bursaria provides movement and protection to the algae.

**Explanation:**

**Symbiosis:**
Symbiosis is a close and long-term relationship between two different species. It can be mutualistic, where both species benefit, or it can be parasitic, where one species benefits at the expense of the other.

**Green Algae:**
Green algae are a group of photosynthetic organisms that belong to the kingdom Plantae. They are characterized by their green color, which is due to the presence of chlorophyll.

**Zoochlorella:**
Zoochlorella is a type of green algae that exhibits symbiotic relationship with certain species of protozoa. It is commonly found in the cytoplasm of the protozoan Paramecium bursaria.

**Paramecium bursaria:**
Paramecium bursaria is a single-celled, freshwater protozoan that belongs to the phylum Ciliophora. It has a characteristic oval or elongated shape and is covered with cilia, which are used for movement and feeding.

**Symbiosis between Zoochlorella and Paramecium bursaria:**
The symbiotic relationship between Zoochlorella and Paramecium bursaria is mutualistic, meaning both species benefit from the association.

1. **Benefits to Zoochlorella:**
- Paramecium bursaria provides a protected and stable environment for Zoochlorella to grow and reproduce.
- The waste products of Paramecium bursaria, such as carbon dioxide, provide a source of nutrients for Zoochlorella's photosynthesis.

2. **Benefits to Paramecium bursaria:**
- Zoochlorella performs photosynthesis and produces oxygen, which is utilized by Paramecium bursaria for respiration.
- The products of photosynthesis, such as glucose, provide a source of nutrients for Paramecium bursaria.
- The presence of Zoochlorella also enhances the survival and reproductive capabilities of Paramecium bursaria, especially under conditions of low light or limited food availability.

**Conclusion:**
The species showing symbiosis with green algae Zoochlorella is Paramecium bursaria. This mutualistic relationship benefits both the green algae and the protozoan, providing them with essential nutrients and protection.