Herbivore ingests plant material with 1000 k j energy form producer and assimilated only 200 k J energy in their blood stream; additionally herbivore invests 120 k j energy in their maintenance. What is production efficiency of that herbivore?

#Question id: 7250

#Unit 5. Developmental Biology

Following statements are regarding to signals that regulate axis extension in chick embryos.

A. In the stage 10 chick embryo, Fgf8 inhibits expression of the retinoic acid (RA) synthesizing enzyme Raldh2 in the presomitic mesoderm and the expression of the RA receptor RARβ in the neural ectoderm, thus preventing RA from triggering differentiation in the caudal-lateral epiblast cells and the caudal-most paraxial mesoderm.

B. Fgf8 inhibits Sonic hedgehog (Shh) expression in the neural tube floorplate, controlling the onset of ventral patterning genes.

C. FGF signaling is also required for expression of Delta1 in the medial portion of the caudal-lateral epiblast cells and promotes expression of Wnt8c.

D. Fgf8 decays in the caudal paraxial mesoderm, Wnt signaling, most likely provided by Wnt8c, now acts to promote Raldh2 in the adjacent paraxial mesoderm. RA produced by Raldh2 activity expresses Fgf8 and Wnt8c.

Which of the following statements are correct?

#Question id: 5795

#Unit 8. Inheritance Biology

Which characteristic of the genetic code lowers the likelihood of mutation.

#Question id: 12746

#Unit 13. Methods in Biology

#Question id: 3256

#Unit 11. Evolution and Behavior

There are three alleles, A1, A2, and A3, whose frequencies are equal abundance. According the Hardy-Weinberg equilibrium

#Question id: 4850

#Unit 8. Inheritance Biology

When F1generation of a dihybrid is allowed to self fertilized, the expected ratio is of genotype when complete linkage?