Spirogyra is a genus of freshwater green algae in the division Chlorophyta. It is commonly found in freshwater environments and is known for its long, spiral-shaped chloroplasts. The cells of Spirogyra are cylindrical or spiral in shape, and they are joined end to end to form a filament. Spirogyra is a primary producer, meaning it is a source of food for other organisms in the ecosystem, and it obtains its energy through photosynthesis.

Spirogyra reproduces both sexually and asexually. During sexual reproduction, two cells fuse to form a zygote which then undergoes meiosis to form new cells. During asexual reproduction, the filaments can break and each fragment can grow into a new filament.

In addition to its importance as a primary producer, Spirogyra also has significant scientific value as a model organism for studying the structure and function of algae, as well as for understanding the process of sexual reproduction in algae.

1. What is the scientific name for Spirogyra?

A. Chlorophyta

B. Oedogonium

C. Spirogyra

D. Zygomycota

2. What type of organism is Spirogyra?

A. Fungus

B. Algae

C. Bacteria

D. Virus

3. How does Spirogyra reproduce?

A. Mitosis

B. Meiosis

C. Binary Fission

D. Sexual Reproduction

4. What is the shape of the Spirogyra cell?

A. Ellipsoidal

B. Spiral

C. Straight

D. Square

5. What type of structure is found in Spirogyra cells?

A. Chloroplasts

B. Vacuoles

C. Nucleus

D. All of the above

6. What is the function of the chloroplasts in Spirogyra cells?

A. Photosynthesis

B. Respiration

C. Digestion

D. Excretion

7. What is the source of nutrition for Spirogyra?

A. Autotrophic

B. Heterotrophic

C. Mixotrophic

D. Parasitic

8. In which environment is Spirogyra commonly found?

A. Salt water

B. Fresh water

C. Terrestrial

D. Marine

9. What type of movement is observed in Spirogyra?

A. Motile

B. Non-motile

C. Flagellated

D. Ciliate

10. How does Spirogyra respond to light?

A. Positive Phototropism

B. Negative Phototropism

C. No Phototropism

D. Both A and B.

11. What is the main structure that differentiates Spirogyra from other algae species?

A. Chloroplasts

B. Nucleus

C. Cell wall

D. Spiral chloroplast

12. What type of thallus does Spirogyra have?

A. Filamentous

B. Parenchymatous

C. Pseudoparenchymatous

D. None of the above

13. What is the significance of Spirogyra in the ecosystem?

A. Primary Producer

B. Secondary Consumer

C. Decomposer

D. Apex Predator

14. What type of cytoplasmic streaming is observed in Spirogyra?

A. Circular

B. Radial

C. Peripheral

D. None of the above

15. What is the mode of asexual reproduction in Spirogyra?

A. fragmentation

B. budding

C. fission

D. all of the above

Answer Key

1. C. Spirogyra
2. B. Algae
3. D. Sexual Reproduction
4. B. Spiral
5. D. All of the above
6. A. Photosynthesis
7. A. Autotrophic
8. B. Fresh water
9. B. Non-motile
10. A. Positive Phototropism
11. D. Spiral chloroplast
12. A. Filamentous
13. A. Primary Producer
14. D. None of the above
15. D. all of the above