Both starch and cellulose are made by stringing together many glucose molecules. However, while starch is easily digested by humans, cellulose is indigestible. The starch polysaccharide has bonds occurring below the sugar rings, while the bonds in cellulose alternate above the ring and below the next ring. How can you explain humans' inability to digest cellulose?
A. The alternating bonds make the cellulose molecule too large and bulky to enter cells for digestion.
B. The acidic molecules found in stomach acid cannot act on the bonds that are above the sugar rings in cellulose.
C. Humans do not eat cellulose.
D. Cellular respiration is only capable of breaking down specific bonds.
E. The enzyme that breaks down starch can only fit the specific bond configuration of bonds below the ring.
Answer: E
You might also like to view...
Each time a diatom reproduces sexually, the size of the daughter cells decreases until diatoms are about 30% of their original size. At this point, they begin to reproduce asexually.
Answer the following statement true (T) or false (F)
Which of the following is a source of water loss in humans? I) urination II) defecation III) breathing
A) I B) II C) III D) I, II, and III
If cells had single-layer membranes like micelles, how would the structures of transmembrane proteins be affected?
A) transmembrane proteins would only possess hydrophilic regions B) transmembrane proteins would possess a hydrophilic region in the cell interior and a hydrophobic region in the extracellular space C) transmembrane proteins would only possess hydrophobic regions D) transmembrane proteins would possess a hydrophobic region in the cell interior and a hydrophilic region in the extracellular space E) the structures of transmembrane proteins would remain the same as if cells had lipid bilayers
Four of the following statements about fossils found on the island of Flores are true. Which one is the exception?
A. They are shorter than modern humans. B. They have very small brains. C. They are 200,000 years old. D. They have a heavy brow ridge. E. They have been described to be like “hobbits.”