Refer to the figure below. The figure shows a simple sponge that lives attached to the ocean floor.The sponge consists of an outer layer of epidermal cells, an inner layer of collar cells and amebocytes, and pore cells that allow water to move from the outside to the inside.The water is propelled by the beating of flagella attached to the collar cells on the inside cavity.Collar cells trap food particles that are digested by the amebocytes.A student claims that a simple sponge could be a model organism used to study how multicellular organisms evolved.Which statement best evaluates this student's claim?
A) The student's statement is correct because the sponge lives attached to the ocean floor and would therefore be a model for multicellular plant evolution.
B) The student's statement is correct because the sponge demonstrates a simple structure made up of cells that have specialized to serve different functions.
C) The student's statement is incorrect because the sponge does not have any recognizable organs or organ systems.
D) The student's statement is incorrect because the sponge has only four different types of cells while other multicellular organisms have many more.
E) The student's statement cannot be evaluated, because there is not enough information to support or refute the claim.

Question

Refer to the figure below.  The figure shows a simple sponge that lives attached to the ocean floor.The sponge consists of an outer layer of epidermal cells, an inner layer of collar cells and amebocytes, and pore cells that allow water to move from the outside to the inside.The water is propelled by the beating of flagella attached to the collar cells on the inside cavity.Collar cells trap food particles that are digested by the amebocytes.A student claims that a simple sponge could be a model organism used to study how multicellular organisms evolved.Which statement best evaluates this student's claim?
A) The student's statement is correct because the sponge lives attached to the ocean floor and would therefore be a model for multicellular plant evolution. 
B) The student's statement is correct because the sponge demonstrates a simple structure made up of cells that have specialized to serve different functions. 
C) The student's statement is incorrect because the sponge does not have any recognizable organs or organ systems. 
D) The student's statement is incorrect because the sponge has only four different types of cells while other multicellular organisms have many more. 
E) The student's statement cannot be evaluated, because there is not enough information to support or refute the claim.

Quizplus · Accepted Answer

The student's statement is correct because the sponge demonstrates a simple structure made up of cells that have specialized to serve different functions. Multicellularity is a complex trait that has evolved many times independently in different lineages. Scientists study simple organisms, such as sponges, to understand how multicellularity evolved and how different cell types and functions arose. Sponges have simple body plans and lack organs and other complex structures found in more derived animals, making them a suitable model organism to study multicellularity evolution.

Refer to the Figure Below