What characteristics of flat worms allow them to use diffusion to excrete waste materials and take up oxygen (and for some kinds, to absorb nutrition from their hosts)?
What will be an ideal response?
In order for these biological processes to occur, there must be a large surface area relative to the volume of the animal. Flatworms achieve a relatively large surface area by being small, very thin, and flat, all of which increase their surface area without substantially increasing their body volume.
You might also like to view...
The primary reason surplus carbohydrates in plants are stored as starch is because:
A. they would otherwise be utilized as energy sources even if such energy was not needed at that time. B. the space they occupy as carbohydrates is needed for other macromolecules. C. energy is needed in the nucleus, and only starch is capable of being transported into the nucleus. D. leaving them as individual monosaccharides would upset the osmotic balance of the cell.
In the light-dependent reactions of
photosynthesis, how do hydrogen ions get back into the stroma?
a. passive diffusion directly across the thylakoid membrane b. active transport accross the thylakoid membrane c. facilitated diffusion across the thylakoid membrane d. active transport through ATP synthase e. passive diffusion through ATP synthase
W hat was the major stumbling block for the acceptance of natural selection as a mechanism for evolution when proposed by Darwin?
a. lack of a fossil record b. lack of observational and experimental data c. lack of a plausible theory of heredity d. lack of evidence for artificial selection
Water has surface tension because ...
What will be an ideal response?