Which of the following short descriptions best describes the body plan of modern sponges?
a. an aggregation of cells built around a water canal system
b. a complete gut with an anterior mouth and posterior anus
c. a complete gut with one opening serving as both mouth and anus
d. a mouth connected to a blind sac in which digestion occurs
e. an aggregation of cells in a random arrangement
Ans: a. an aggregation of cells built around a water canal system
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Which of the following are molecular mediators of inflammation?
A) chemokines B) cytokines C) erythrocytes D) both chemokines and cytokines
The main function of the endomembrane system is building and modifying _____ and _____
Fill in the blank(s) with correct word
Answer the following statements true (T) or false (F)
1.Weak muscular contraction could be due to either poor binding of actin and myosin or to insufficient calcium available to stimulate contraction. 2.Bones can provide calcium to the rest of the body if it is needed. 3.Bones have blood vessels attached to their surfaces but not penetrating them. 4.The long bones of the human body begin as cartilaginous structures in embryos. 5.The long bones of the human body elongate during development via growth plates at their ends.
The letter “C” in the above figure represents which
teeth? a. incisors b. molars c. canines d. premolars e. none of these