The first multicellular animals to develop neurons were
A) flatworms and sea urchins.
B) mollusks and sea stars.
C) fish and sea monkeys.
D) jellyfish and sea anemones.
E) segmented worms and sea horses.
D) jellyfish and sea anemones.
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What is the function of the basal nuclei in normal motor control?
A. They provide a perceptual awareness related to specific sensory inputs from the eyes, nose, and mouth. B. They provide a sense of the cause-and-effect relationships between muscle actions and the consequences of taking these actions before executing them. C. They participate in a looping neuronal circuit through which motor impulses are sent to facilitate or suppress movements. D. They provide a general perceptual awareness associated with somatosensory inputs from the skin, muscles, and joints. E. They form an initial intention to move, such as when you decide to pick up an object.
In some proteins, disulfide covalent bonds form between two _________ amino acids.
Fill in the blank with correct word.
Cytotoxic T-lymphocytes that have killed a foreign cell may transform into
A. memory B-lymphocytes. B. natural killer cells. C. plasma cells. D. helper T-lymphocytes. E. None of the choices is correct.
The central, raised area of the breast where the newborn suckles is called the
A) lactirferous duct. B) areola. C) nipple. D) fornix. E) lactiferous sinus.