A first exposure to an allergen stimulates the immune system to make ________
a. IgM
b. IgD
c. IgA
d. IgE
d
You might also like to view...
Cellulose is a polymer of ________, a common monosaccharide.
Fill in the blank(s) with the appropriate word(s).
The central column of conductive tissue in the root system is known as a(n) ________
a. vascular cylinder b. endodermis c. epidermis d. root cortex e. pericycle
Impressive was a champion Quarter Horse stallion with a magnificent muscular physique, a trait that he passed on to dozens of offspring. However, many of Impressive's offspring developed periodic muscular twitching that sometimes left the horses temporarily unable to move. Some horses even died. As it turns out, Impressive's award-winning physique was due to a mutation in a single, protein-encoding gene, resulting in hyperexcitable muscle (which contracts even in the absence of a stimulus from its motor neuron). Which is NOT a plausible explanation for the identity of the abnormal muscle protein in Impressive and his offspring?
A. tropomyosin that is unable to bind to actin B. acetylcholine receptors that function in the absence of acetylcholine C. over-active troponin molecules D. leaky Na+ channels E. overactive Ca2+ pumps in the membrane of the sarcoplasmic reticulum Clarify Question · What is the key concept addressed by the question? · What type of thinking is required? Gather Content · What do you know about excitation of muscles? What other information is related to the question? Choose Answer · Given what you now know, what information is most likely to produce the correct answer? Reflect on Process · Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
Pollen grains germinate
a. in the style. b. in the ovule. c. on the stigma. d. at the micropyle. e. in the ovary.