Which of the following is NOT a somatic cell?
a. liver
b. skin
c. bone
d. blood
e. sperm
E
You might also like to view...
The forelimb of a bat and the forelimb of a bird are examples of structures.
A. homeotic B. analogous C. homologous D. vestigial E. heterologous
Place the following events of the acrosomal reaction in the correct chronological order.(1) The acrosome releases hydrolytic enzymes.(2) Sperm-binding proteins on the membrane bind the sperm.(3) Sperm nucleus enters the egg.(4) Sperm and egg plasma membranes fuse.(5) Sperm contacts the egg's jelly coat.
A. 5,1,2,4,3 B. 5,2,4,3,1 C. 1,5,4,3,2 D. 3,5,2,1,4 E. 1,2,4,3,5
Based on experiments with amphibian embryos, Spemann and Mangold found that
A) transplanted cells always died. B) transplanted cells completely undifferentiated into random masses of tissue. C) transplanted cells always formed a whole new embryo. D) in most cases, transplanted donor cells assumed the developmental fate of the area to which they were transplanted in the host. E) donor cells maintained their original differentiation no matter where in the host they were transplanted.
The Ras protein is a GTPase that functions in many growth-factor signaling pathways
In its active form, with GTP bound, it transmits a downstream signal that leads to cell proliferation; in its inactive form, with GDP bound, the signal is not transmitted. Mutations in the gene for Ras are found in many cancers. Of the choices below, which alteration of Ras activity is most likely to contribute to the uncontrolled growth of cancer cells? (a) a change that prevents Ras from being made (b) a change that increases the affinity of Ras for GDP (c) a change that decreases the affinity of Ras for GTP (d) a change that decreases the rate of hydrolysis of GTP by Ras