Platelets are
A) large cells that lack a nucleus.
B) large cells with a prominent, indented nucleus.
C) small cells with a many-shaped nucleus.
D) fragments of large cells.
E) small cells that lack a nucleus.
D) fragments of large cells.
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The cecum is part of the:
A) small intestine B) large intestine C) esophagus D) mouth
Wernicke's area functions mainly for
a. control of limb movements b. hand-eye coordination c. language comprehension d. memory e. vision
Callopistes maculatus, the dwarf tegu, is a teiid lizard that occurs in desert habitats in Chile
A study of its daily activity cycle in summer showed a decrease in activity during midday, although the body temperatures of the lizards that were active in midday were not different from the body temperatures of lizards that were active in the morning or afternoon. That observation is not consistent with the hypothesis that midday temperatures are so high that the lizards must seek shelter to avoid overheating. Apparently dwarf tegus in this habitat are able to maintain their normal activity body temperatures throughout the day. What alternative hypothesis can you suggest to account for the decrease in activity of dwarf tegus in midday? If your hypothesis is correct, what additional concern does it suggest about the potential effect of global climate change on lizards?
How are T cells "introduced" to antigens?
A. T cells bind to and phagocytose antigens. B. Antibodies immobilize the antigens for T cell recognition and destruction. C. Antigen-presenting cells link antigenic peptides to MHC proteins to which T cells will attach. D. T cells wait in the blood until an antigen collides with them and binds to their TCR.