Biology Multiple Choice Questions on “Ecosystem – Hydrarch Succession”.
1. What is the sequence of successional stages occurring in water called?
a) Xerarch succession
b) Hydrarch succession
c) Ecological succession
d) Biological succession
Answer: b
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession. It is also known as hydrosere and starts in a newly formed pond or lake.
2. Which of the following succession starts with the colonization of phytoplankton in the water?
a) Hydrarch succession
b) Xerarch succession
c) Biological succession
d) Ecological succession
Answer: a
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession or hydrosere. It usually starts with the colonization of small phytoplanktons. These organisms act as the pioneering species in hydrosere.
3. Who replaces the phytoplanktons in a hydrarch succession?
a) Zooplankton
b) Rooted-submerged plants
c) Angiosperms
d) Fishes
Answer: b
Clarification: A hydrarch succession starts with the colonization of small phytoplanktons. These phytoplanktons, later with time are replaced by rooted-submerged plants in a hydrarch succession. Some examples of the rooted-submerged plants are Ceratophyllum, Chara, Elodia, Potamogeton, etc.
4. Who replaces the rooted-submerged plants in a hydrarch succession?
a) Free-floating plants
b) Phytoplankton
c) Zooplankton
d) Rooted-floating angiosperms
Answer: d
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession or hydrosere. The rooted-submerged plants with time are replaced by rooted-floating angiosperms. An example of a rooted-floating angiosperm is water lily.
5. Who replaces the rooted-floating angiosperms in a hydrarch succession?
a) Phytoplankton
b) Zooplankton
c) Free-floating plants
d) Rooted-submerged plants
Answer: c
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession or hydrosere. The rooted-floating angiosperms with time are replaced by free-floating plants in a hydrarch succession. Some examples of the floating plants are Pistia, Nymphaea, Pistia, Nymphaea, etc.
6. Who replaces the free-floating plants in a hydrarch succession?
a) Rooted-submerged plants
b) The reed-swamp
c) Free-floating angiosperms
d) Phytoplankton
Answer: b
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession or hydrosere. The free-floating plants with time are replaced by the reed-swamp in a hydrarch succession. Some examples of the reed-swamp plants are Bothrioclova, Phragmites (Reed), Typha, etc.
7. Who replaces the reed-swamp in a hydrarch succession?
a) Rooted-submerged plants
b) Phytoplankton
c) Free-floating angiosperms
d) Marsh-meadow
Answer: d
Clarification: The sequence of successional stages occurring in water is known as hydrarch succession or hydrosere. The reed-swamp with time is replaced by the marsh-meadow in a hydrarch succession. Some examples of the marsh-meadow plants are Caltha, Gallium, Mentha, Cicuta, etc.
8. What is the marsh-meadow replaced by in a hydrarch succession?
a) Free-floating angiosperms
b) Rooted-submerged plants
c) Scrub
d) Free-floating plants
Answer: c
Clarification: The marsh-meadow with time is replaced by the scrub in a hydrarch succession. The scrub stage is also known as the woodland stage. Some examples of the plants of the woodland community are Acacia, Cassia, Cephalanthus, Salix, etc.
9. What is the woodland stage replaced by in a hydrarch succession?
a) Free-floating angiosperms
b) Scrub
c) Rooted-submerged plants
d) Trees
