Question

Yeast and mushroom are different from spirogyra because they
a. Cannot carry out photosynthesis
b. Lack of cellulosic cell wall
c. Reproduce by sexual methods
d. Are terrestrial as well as aquatic

Answer 1

Spirogyra is the filamentous green algae, and it got its name because of the helical or spiral arrangement of a chloroplast, and there are almost 400 species of spirogyra in the earth, and they are normally a freshwater habitat.

Complete answer:
Spirogyra
- They are 10 to 100 micrometers in width and they are several centimeters in length.
- They are common in freshwater habitats, and they form slimy filamentous green masses.
- Generally, they grow under the water, and when there is enough sunlight and warmth, they produce a large amount of oxygen.
- They have a cell wall, nucleus, and spiral-shaped chloroplast, where spirogyra undergoes photosynthesis, and prepare food on its own.

Yeast
- Yeast is a member of fungus, it is a eukaryotic, unicellular microorganism, but some form into multicellular by connecting budding cells which are also known as pseudohyphae.
- The diameter of the yeast 3 to 4 micrometers.
- They present as both obligate aerobes and facultative anaerobes.
- When coming to nutrition, they do not do any photosynthesis, but they are chemoorganotrophs, which means they depend on organic compounds as a source of energy.

Mushroom
- Mushroom is a fleshy spore-bearing fruit body, where it belongs to the fungus.
- Mushrooms mostly grow above the ground, and sometimes it also is grown underground, or on any wooden decay trees, etc
- Most they grow in moist damp areas and in rainy seasons, where they can grow within one day.
- They can grow by themselves, and they are grown for edible purposes, and mushrooms also won’t perform any photosynthesis.

Hence, the correct answer is option (A).

Note: Spirogyra undergoes sexual reproduction by two types of conjugation, where the difference between scalariform conjugation and in lateral conjugation is, in the first one conjugation occurs between two or more filaments, while in the lateral conjugation it occurs within the 2 cells of a single filament.