A mixed solution of water and small molecules is exposed to a cell membrane and allowed to interact for an hour. Which molecule would be most likely to cross the phospholipid bilayer without the aid of transport proteins and diffuse across the membrane the fastest?
A. O2
B. Estrogen (C18H24O2)
C. NH4+
D. Na+
E. CH3COO-
Answer: A
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What is a major difference between the extracellular matrix (ECM) of a plant cell and the ECM of an animal cell?
A) Plant ECM is composed primarily of proteins, whereas animal ECM is mainly carbohydrates. B) Plant ECM is primarily carbohydrate in nature, whereas animal ECM is mainly proteins. C) Plant and animal ECMs are quite similar in structure and function. D) ECM components in plant cells are released extracellularly by the Golgi stacks, whereas lysosomes do this in animal cells.
Using a host defective in proteases is likely to be necessary when engineering
A) a complete metabolic pathway requiring several different enzymes. B) overproducing proteins. C) production of a small protein. D) transgenic animals with immune systems.
Mendel studied what he called characters and traits. What is the relationship between these terms?
a. Characters are heritable characteristics; traits are variations of characters. b. Traits are heritable characteristics; characters are variations of traits. c. Characters are the unknown packages transferred to the next generation; traits result from this transfer. d. Characters are passed to the next generation; traits are never passed to the next generation. e. Characters and traits are synonymous in Mendel's writings.
You isolate a compound that is insoluble in water, has alternating single and double bonds, and has a bright orange
color. You correctly conclude that this compound is a: a. protein. b. nucleic acid. c. polysaccharide. d. steroid. e. carotenoid.